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Polychaete Research Newsletter (No 14 April 1992) - Part 1
Published by BioLine
Code: NL93010
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ISSN 0961-320X
Editor: Chris Mettam
School of Pure & Applied Biology, University of Wales College of
Cardiff, PO Box 915, Cardiff CF1 3TL, UK
The Polychaete Research Newsletter is a communication of the
Polychaete Society
It is not a publication for the purposes of the International
Code of Zoological Nomenclature
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Polychaete Society Meetings
The success of the 1991 Polychaete Colloquium in Edinburgh, the
proceedings of which are reported in this issue of Polychaete
Research Newsletter, prompted a call for follow-up meetings on
a regular basis. It was suggested that a useful format would be
two days devoted to talks and poster sessions followed by two
days of taxonomic workshop and the proposition was made that
there should be a local United Kingdom meeting of the Polychaete
Society in the years when the International Polychaete Conference
was not being held. The International Polychaete Conference will
take place this year at Angers, France and so a local Polychaete
Society meeting is planned for 1993.
Polychaete Colloquium, Edinburgh April 1991
organised by Susan Chambers and Gordon L.J. Paterson
---------------------------------------------
Importance of Taxonomy
Andrew S.Y. Mackie
Department of Zoology
National Museum of Wales, Cardiff
The accurate and consistant recognition of different zoological
taxa is fundamental to all marine biological investigations
whether taxonomic, ecological, physiological or behavioural. To
most workers this means identification to species level.
The status of polychaete taxonomy in northern European waters is
currently undergoning a re-appraisal after many decades of
neglect. The 1990's promise much in the way of taxonomic
revisionary work as well as the description of new taxa. Recent
publications have highlighted this with the description of new
genera (e.g. Atherospio, Baldia) and species (e.g. Tharyx
vivipera, Eulalia mustela, Eumida ockelmanni). In addition, a
number of previously compounded species have been re-established
(e.g. Nephtys assimilis, Amphicteis midas, Eulalia ornata) and
foreign species may be introduced (e.g. exotic serpulids,
Marenzelleria viridis). As an estimate, there are probably around
850 polychaete species known from UK waters, however, given the
current upsurge in interest, perhaps 50-100 more will be added
over the next few years. A number of new identification manuals
have already appeared as part of the ongoing Synopsis of the
British Fauna and Marine Invertebrates of Scandinavia series.
These will provide valuable replacements of outdated (though
still vital) works such as Fauvel (1923 & 1927) and
Hartman-Schröder (1971).
Unfortunately polychaetes are still regarded as 'difficult'
to identify in the eyes of most marine biologists. This is
clearly a problem, especially when polychaetes are commonly found
to dominate temperate soft bottom habitats. Recently several
papers (e.g. Warwick 1988, Warwick et al. 1990, Platt et al.
1990) have indicated that it may be possible to carry out
successful ecological assessments of marine benthic habitats by
only identifying to generic or family level. This approach is
obviously appealing to those involved in benthic
survey/monitoring work, which is labour intensive and where time
constraints are often paramount, but a number of important
objections remain and caution is advised!
To support the theory that a generic level analysis is as
good as a species level one it is necessary to determine all
species present prior to any comparison, however, in the Warwick
& Platt et al. papers a number of polychaetes were not apparently
determined beyond family (Phyllodocidae, Syllidae, Arabellidae,
Dorvilleidae, Ampharetidae). Moving to a higher taxonomic level
clearly involves a loss of information, the extent of which will
depend both on the structure of the fauna under investigation and
the accuracy of the identifications carried out, as well as
features of the sampling regime (e.g. sieve size) and data
processing. For example, an examination of part of an NMW survey
of the Irish Sea reveals a loss of 25% of the polychaete taxa
when treating the data at the generic level. A number of the
published examples (Warwick 1988) detail major disturbance, but
the analytical techniques used in monitoring programmes need to
be sensitive to the subtle changes that precede the development
of these undesirable situations.
As a simple example a synthetic data set of 3 stations (8,
7 and 4 species respectively), each with 190 individuals
distributed among a total of 10 species and 4 or 6 genera, was
examined. Application of similarity measures to both binary
(Jaccard coeff.) and log transformed quantitative (Bray-Curtis
measure) data demonstrated how the relationships could change in
relation to both the number of taxa and the distribution of
individuals among the taxa. Consideration of diversity (H',
Margalef's d) also showed how differences between stations could
decrease/disappear as the number of taxa were reduced.
References
Platt, H.M., Warwick, R.M., Clarke,K.R., Agard, J. & Gobin, J.
(1990). Benthic communities and disturbance in a subtropical
marine environment. Progress in Underwater Science, 15, 43-54.
Warwick, R.M. (1988). The level of taxonomic discrimination
required to detect pollution effects on marine benthic
communities. Marine Pollution Bulletin, 19, 259-268.
Warwick, R.M., Platt, H.M., Clarke, K.R., Agard, J. & Gobin, J.
(1990). Analysis of macrobenthic and meiobenthic community
structure in relation to pollution and disturbance in Hamilton
Harbour, Bermuda. Journal of experimental Marine Biology and
Ecology, 138, 119-142.
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Down the Slippery Slope: A Study of Polychaete Assemblages from
Bathymetric Transects in the Rockall Trough
Gordon L. J. Paterson (*), P. John D. Lambshead (*) & John D.
Gage (+)
(*) Department of Zoology, British Museum (Natural History),
London, SW7 5BD
(+) Scottish Marine Biological Association, Dunstaffnage Marine
Laboratory, PO Box 3 Oban, Argyll, PA34 4AD
"There is much to be said for the view that the complexes of
environmental factors determining plant distributions can be
indicated and measured better indirectly by the plants
themselves...". D.W. Goodall, 1954
The same can be said of polychaetes.
Analysis of patterns of bathymetric distribution is a
necessary prelude to determining depth related forces which
structure assemblages. This presentation will discuss the changes
in polychaete species distributions from two transects down the
Hebridean Slope and from a permanent station on the floor of the
Trough. Two indirect gradient methods were used, detrended
correspondance analysis and nonmetric multidimentional scaling.
The faunistic similarity of stations along the transects were
also calculated using NESS and ecocladistics. Finally, changes
in trophic groups within the assemblages were investigated.
A weak gradient from 1000m2900m was detected, and with the
exceptions of stations at 1000m and 1200m, the remainder had a
high (>>50%) faunal similarity. The role of the hydrodynamic
regime of the Trough and the gross sedimentary features in
forming this pattern was investigated. The diversity of all
trophic groups declined with depth and there appeared to be
little change in the relative proportions of the various groups.
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The influence of Sabellaria reef on Sublittoral Community
Structure
Chris Mettam
School of Pure and Applied Biology, University of Wales College
of Cardiff, Cardiff CF1 3TL
The distribution of Sabellaria reef in the Bristol Channel and
Severn estuary was determined by systematic sampling with a Day
grab (area 0.1m2) during the months of April and May 1988. The
results (Mettam et al , 1989) extend and confirm earlier
observations of sublittoral Sabellaria reef in the vicinity of
Cardiff (Purchon, 1948). Surprisingly S. alveolata was the
dominant species and the more usual sublittoral species S.
spinulosa was uncommon.
The grid for sampling was spaced at intervals of 1.5 km.
All stations where Sabellaria was recorded are illustrated in
Figure 1 (not available), which shows two main concentrations of
records, a more upstream one located centrally in the estuary and
another in the southern sector of the Bristol Channel. These
large patches of Sabellaria are associated with differences in
substratum. Upstream, east of an approximate longitude 3° 15'W,
Sabellaria occurred at virtually every station where there was
an exposure of bedrock or stabilised boulders: the absences
indicate where there was a substantial cover of mud or sand. At
these stations, Sabellaria, when present, appeared to make thick
reefs and samples were bites from the reef surface. Poor reef
development occurred on most of the second patch, limited to a
thin covering of Sabellaria tubes over cobbles and boulders.
West of an approximate longitude 3° 20'W many stations probably
consisted of bedrock or boulders, without a covering of fauna,
and often no sample or only a few smooth cobbles was recovered:
presumably the high level of bed stress and scour and perhaps a
low level of supply of sand grains combined to prevent good reef
growth. Alternate stations on the sampling grid were omitted in
that part of the survey area and the few positive records of
Sabellaria there are of occasional, isolated tubes.
In the axial part of the Channel and estuary, where currents
are strongest, the benthos was impoverished: epifauna and infauna
were often absent. The presence of Sabellaria reef was
associated with a diversity of species. Apart from Sabellaria
itself, the rank order of the top ten species most frequently
recorded in a subset of 32 reef samples, grouped by TWINSPAN, was
Typosyllis armillaris (20), Eulalia tripunctata (19), Golfingia
vulgaris (18), Melinna cristata (15), Mediomastus fragilis (14),
Harmothoe impar (12), Arenicola marina (juvenile) (11), Pygospio
elegans (11), Sphenia binghami (11), Autolytus prolifer (10), and
that of the top ten most numerous species was Arenicola marina
(juvenile)(522), Mediomastus fragilis (384), Melinna cristata
(293), Golfingia vulgaris (206), Eulalia tripunctata (201),
Gammarus salinus (160), Typosyllis armillaris (155), Harpinia
pectinata (88), Tubificoides brownae (61), Exogone naidina (57).
The reef presumably provided the necessary sediment trap,
structured habitat and refuge for modest development of a benthic
community in an environment, otherwise physically disturbed to
the point of being defaunated by sediment mobility and tidal
scour.
The observations have implications for any method of
assessment of disturbance in benthic communities which compares
the relative dominance of small and large species, notably the
'abundance biomass comparison' (ABC) method (Warwick, 1986).
Sabellaria alveolata is a long lived, resilient species and was
the numerically dominant species (61% of total specimens) as well
as by far the largest, having an individual biomass 12 orders
of magnitude greater than that of the small animals sharing its
reef. In plots of cumulative abundance and biomass by rank order
therefore, the first ranking Sabellaria will comprise an even
greater percentage of the biomass than of the abundance and this
will raise the biomass curve above the abundance curve in a way
that indicates 'stability' and an 'undisturbed' state (Warwick,
1986). The description of the assemblage of species as an
undisturbed community, inferred from the ABC plot, is surely
misleading when the community occurs in an extremely stressful
physical regime and is vulnerable to breakdown with the loss of
all its constituent members. The same quantitative picture might
apply to other communities in which small species depend on the
habitat structuring ability of a larger, tube-building polychaete
or any other, larger, resilient member of the infaunal
association. A different plot would result if the habitat
structuring species was not a member of the infauna but, say, a
sea grass with a network of rhizomes penetrating the sediment.
The two situations might be biologically analagous in terms of
community stability but an interpretation by the ABC method, now
excluding the plant component, would be different.
A community like that of the Sabellaria reef of the Severn
estuary, dependent on one controlling species for its existence,
can probably be distinguished from an 'undisturbed community' as
described by Warwick (1986) because the same species (S.
alveolata in this instance) occupies first rank positions for
both abundance and biomass curves. However, a misleading
impression might arise if comparisons between communities are
made from a numerical index of the difference between the two
curves (McManus & Pauly, 1990) without regard to the actual
species composition of the communities. Reefs which provide for
the (possibly transient) establishment of communities with
'undisturbed' characteristics in an environment of extreme
physical disturbance could persist for years after death of their
architects and builders, the Sabellaria , altering the ABC
impression yet again.
Acknowledgement.
I am grateful to Dr Maura Conneely and Ms Sarah White (who
between them did the bulk of sampling, sorting and analysis) for
their tireless participation in the original survey and to Sarah
White for preparing Figure 1.
References
McManus, J.W. & Pauly, D. (1990). Measuring ecological stress:
variations on a theme by R. M. Warwick. Marine Biology , 106,
305-308.
Mettam, C., Conneely, M.E. & White, S.J. (1989). Distribution of
subtidal benthos associated with sediments, Severn Barrage
Development Project Task 3.7 (i), Report No. SBP 38.
Purchon, R.D. (1948). Studies on the biology of the Bristol
Channel XVII. The littoral and sublittoral fauna of the northern
shores, near Cardiff. Proceedings of the Bristol naturalists
Society, 27, 311-329.
Warwick, R.M. (1986). A new method for detecting pollution
efffects on marine macrobenthic communities. Marine Biology ,92,
557-562.
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The feeding in the Cirratulids Dodecaceria fimbriata and
D. concharum
Peter H. Gibson
46 Craighouse Avenue, Edinburgh EH10 5LN
This study was carried out to determine whether differences
existed in the feeding behaviour of D. fimbriata and D. concharum
that would explain their coexistence in the same niche.
Samples of shale containing the two species were collected
from rock pools on the lower beach of Cullercoats Bay,
Northumberland. They were kept in the The Dove Marine Laboratory
circulating sea water aquarium. The feeding behaviour of
specimens while in their burrows was observed with a stereoscopic
microscope. Faeces was collected from specimens that had been
extracted from their burrows and then placed in filtered sea
water in Petri dishes on the bench. Detritus deposited from the
aquarium sea water system was collected for comparison.
Feeding behaviour
The two species lay doubled up within flask-shaped burrows.
The head, branchial cirri and a pair of tentacular palps with
ciliated grooves projected from the entrance. The anus lay behind
the head. During feeding the extended tentacles ranged
independently around the burrow by writhing and creeping
movements. As they moved over the substratum, detritus adhered
to a mucous strand in each ciliated groove. Cilia along the edge
of each groove swept water-bourne particles into the groove.
When both species were feeding normally the tentacles were
occasionally drawn across the head in a wiping action which
transferred the mucous strand to the mouth. The largest particles
were rejected by the upper lip of the mouth. In the calm
conditions of the laboratory aquarium the faeces accumulated at
the entrance of the burrow on the opposite side to the mouth
although this was not seen in the field. Carmine particles fed
to specimens from their burrows took 1-2 hours to pass through
the gut.
A buccal organ, seen in histological sections of both
species, consisted of a crescent shaped muscle that passed along
the lower posterior edge of the mouth. During feeding the muscle
contracted to form a ball which partially protruded from the
mouth. Retractor muscles attached to the body wall pulled the
buccal organ with the mucous food strand into the mouth. Cilia
along the edge of the mouth appeared to assist the movement of
the mucous strand.
Faecal particle size
Faeces of specimens of both species that had been dept in
the aquarium consisted largely of sand particles. These were
pipetted onto glycerol-coated microscope slides. The maximum
diameter of randomly selected particles was measured at X40
magnification using a micrometer eyepiece. The mean for each
species was the same (mean 32†m, n=71, SD=10) and very similar
to that for particles settling from the aquarium water system
(mean=24 †m, n=72, SD=11). This suggested that the discrimination
by the two species was slight.
Sand particles and detritus supplied by the aquarium water
system appeared to be an adequate diet since specimens kept in
the aquarium for up to a year grew at a similar rate to those on
the shore (Gibson & Clark 1976; Gibson 1977).
Distribution of burrows
The nearest neighbour distances were measured for occupied
burrows in two intact rock samples. The mean distance between the
burrows was 4.0mm (n=58, SD=1.8). The species within burrows,
however, could not be determined in situ. The feeding areas
clearly overlapped since the tentacles of the species reached up
to 25-30mm. On occasions the tentacles of different individuals
"tangled" with one another.
From four rock samples 122 specimens of D. fimbriata and 20
specimens of D. concharum were extracted, a ration of 6:1. The
polychaete Polydora ciliata also occupied the same substratum.
On one occasion a small, asexually produced fragment of D.
fimbriata was found in an empty Polydora burrow.
Conclusion
The two species of Dodecaceria were found to be unselective
deposit feeders, using the same range in size of particles
collected in an identical manner. The relative numbers of each
species in the substratum can possibly be accounted for by
differences in their reproductive success.
D. fimbriata reproduces asexually within its burrow and
sexually by epitoky (Gibson & Clark 1976). D. concharum is
pathenogenetic and either spawns into its burrow (Gibson 1977)
or is viviparous (Marcel 1961-62). In Cullercoats Bay,
recruitment by trochophore larvae probably does not occur since
the settling larvae would be eaten. Since both species are unable
to initiate their own burrows (Evans 1969; Gibson & Clark 1976),
recruitment probably depends on asexually and pathenogenetically
produced juveniles being too large to be eaten. They would be
free to find burrows left empty by spawning epitokes or through
death of individuals.
References
Evans, J.W. (1969). Borers in the shell of the sea scallop
Pecopecten magellanicus. Am Zool 9: 775-782
Gibson, P.h. (1977). Reproduction in the cirratulid polychaetes
Dodecaceria concharum and D. pulchra J Zool, Lond 182: 89-102
Gibson, P.H. & Clark, R.B. (1976). Reproduction of Dodecaceria
caulleryi (Polychaeta: Cirratulidae). J mar biol Ass UK 56:
649-674
Marcel, R. (1961-62). Sur quelques larves aberrantes de
Dodecaceria concharum Oersted (Annélide: Polychaète). Mém Soc
natn Sci nat math Cherbourg 50 Ser 5 10: 61-67
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A Brief Account of Work Presently Undertaken on Serpulid Taxonomy
T. Gottfried Pillai
Department of Zoology, British Museum (Natural History)
London SW7 5BD
Among the studies on serpulid taxonomy presently undertaken by
the author is a revision of the genus Serpula Linnaeus, 1758. A
major factor contributing to the problems within the genus has
been the inadequacy of the characters on which the generic
definition is based. Linnaeus's Latin definition of the genus
Serpula merely gave a brief description of its tube; and that of
its type, S. vermicularis, includes a similar description of the
tube, and the animal within it as merely having an extensible
proboscis, which was shown by later workers to be an operculum.
During this early period, even certain polychaetes without a
calcareous tube, for example, Serpula penicillus Linnaeus 1758,
a sabellid, were included under Serpula. Among the hundred and
fifty or so species listed in Hartman's (1959) Catalogue of
Polychaetes, as having been described under Serpula, are those
recognized today as belonging to such diverse genera such as:
Hydroides Gunnerus 1768, Spirobranchus Blainville 1818, Protula
Risso 1826, Pomatoceros Philippi 1844, Placostegus Philippi 1844,
Sclerostyla Morch 1863, Crucigera Benedict 1887, Vermiliopsis
Saint-Joseph 1894, and spirorbid genera.
An approach to the revision of the genus Serpula has been
the testing of characters that were used in the past, first of
all, to define the genus and, secondly, to separate its species.
Studies are also being made on their variations within species,
inter-specific overlaps and ontogenetic changes. It was found
that the application of some of the characters to the known
species, as well as those to be described on the basis of the
present studies, raises serious problems.
Considering the most obvious structure, the operculum, only
one state pertaining to its shape is normally mentioned: that
it is funnel shaped, or more or less funnel-shaped. However, as
the figures of opercula of the known species show, they may also
have other shapes. Some recently described species have opercula
which are described as bell-shaped. This leaves one with the
option of either including a range of main shapes, or not
mentioning its shape all. Of course, this would be on the
assumption that the genus Serpula should have an operculum. What
if, as the studies underway have shown, there are species in
which an operculum is not developed? There are also problems
with regard to the other characters used to define the genus, for
example the bayonet setae. While the generic definition usually
states that bayonet-shaped collar setae have two processs at the
base of the blade, those of Serpula massiliensis Zibrowius, 1968,
and others, have several processes or teeth.
The character states used to separate species cause even
more problems. Taking the operculum again, besides the shape,
which may be characteristic for a given species, the range in
number of marginal lobes is also normally given. Although this
appeared to be useful when dealing with the few species known
earlier, it is becoming evident that it has to be used with
caution as the ranges prevailing in those species are better
known and those of some new species to be described are taken
into consideration, since there are inter-specicfic overlaps. A
similar situation prevails with regard to other character states
such as the number of radioles and abdominal segments.
During the century and four decades that followed Linnaeus'
Serpula vermicularis, thirteen more species of Serpula were
described by various authors, of which seven were from Europe and
the Mediterranean, and one each from the Pacific coast of USA,
Alaska, Japan, Australia, Antarctica and Patagonia. As shown in
Hartman's Catalogue, those thirteen species had either been
synonymized with, or considered possibly synonymous with, Serpula
vermicularis Linnaeus 1767. However, in 1984, ten Hove and
Jansen-Jacobs recognized three of them, S. columbiana Johnson,
1901, S. narconensis Baird, 1861, and S. jukesii Baird, 1865, as
valid. From the work hitherto carried out on the revision, it
appears as though more of those species may turn out to be valid.
Several more species have been described in recent years.
The search for additional characters yielded one that had
not been hitherto observed, namely, internal tube structures.
Examination of collections from various geographical locations
revealed the existence of several species, each with its own
arrangement of internal tube structures and other characters.
Together they constitute a cohesive group which is separable
from the rest of the genus Serpula, and are being described in
a joint paper (Pillai & ten Hove) to be published shortly. An
account of their phylogeny, with discussions on some evolutionary
trees generated with programs such as Hennig86, Paup and
MacClade, will be presented in another paper (ten Hove & Pillai).
The possibility that additional species with other
character-state combinations, both living and fossil, may be
discovered is not being ruled out. Another paper (Pillai) will
deal with some fossil members of the group and their
palaeogeography.
A study of serpulids collected by Pat Hutchings from the
Kimberleys District of Australia is nearing completion. There
are some new and interesting species belonging to other genera
in the collection.
Acknowledgements
I wish to express my thanks to the Keeper of Zoology, Natural
History Musem, London, for research facilites, and the
Systematics Association, for funds provided in connection with
the presentation of this talk at the Polychaete Colloquium.
References
Hartman, O. (1959) Catalogue of the Polychaetous Annelids of the
world , Parts I & II. Allan Hancock Found. Occas. Pap. 23:
1-628.
Hove, H. A. ten, and Jansen-Jacobs, M. J. (1984) A revision of
the genus Crucigera (Polychaeta; Serpulidae); a proposed
methodical approach of serpulids, with special reference to
variation in Serpula and Hydroides. Linn. Soc. of NSW.
Proceedings of the First International Polychaete Conference,
Sydney, (Ed.) P.A.Hutchings: 143-180.
Linnaeus, C. (1758) Systema Naturae (ed. 10) 1: 786-788.
Zibrowius, H. (1968) Etude morphologique, systematique et
ecologique, des Serpulidae (Annelida Polychaeta) de la region de
Marseille. Rec. Trav. St. Mar. End., Bull. 43(59): 81-252.
---------------------------------------------
Life Cycle and Population Dynamics of Myzostoma cirriferum
(Annelida, Myzostomida)
I. Eeckhaut and M. Jangoux
Laboratoire de Biologie Marine; Université de Mons-Hainaut, 19,
Av. Maistriau, 7000 Mons, Belgium
Myzostomids are polychaete-related annelids that always are
associated with echinoderms and whose development and ecology are
poorly known. Investigations were conducted on the larval,
metamorphic and postmetamorphic stages of Myzostoma cirriferum
as well as their population dynamics. Individuals of M.
cirriferum were collected with their hosts (Antedon bifida) at
Morgat (Brittany, France) by SCUBA diving (10 m. depth) during
the years 1988 (September, December), 1989 (March, May,
September) and 1990 (January, March, May).
Larvae were maintained alive for ten days. The 2-days old
larvae are pear-shaped, ciliated trochophores of 40 †m long. They
develop into metatrochophores (5-days old) that measure ca. 70
†m long and are characterised by a buccal aperture, two pairs of
4 setae and an extensible pygydium. Metamorphic larvae lose their
setae and cilia while a trunk and three ventral folds develop.
Three postmetamorphic stages occur in M. cirriferum that are the
juvenile stage (size range: 100 to 500 †m long), the male stage
(size range: from 500 to 700 †m long), and the hermaphroditic
stage (size range: 700 to 2,400 †m long. Juveniles and early
males live attached to the ambulacral grooves of the pinnules of
their hosts while late males and hermaphroditics move freely on
the host body wall.
The frequency and rate of infestation depend on both the
period of the year and the size of the comatulid host. Whatever
the period, infestation of comatulids smaller than 1 cm (arm
length) is almost nonexistent while infestation of those larger
than 4 cm (arm length) is almost 100 %. The rate of infestation
of comatulids is the highest in March (with a maximum of 71
myzostomids per host); it is the lowest in December (with a
maximum of 11 myzostomids per host). Postmetamorphic individuals
should have a life span of about one year: the number of
juveniles and males is the highest in February and March;
afterwards the number of hermaphroditics increases to dominate
the population from May to December.
--------------------------------------------
Recent advances in the reproductive biology of the lugworm
Arenicola marina (L.).
A.A. Pacey (*) & M.G. Bentley (-)
Gatty Marine Laboratory, University of St. Andrews, St. Andrews,
Fife, Scotland, KY16 8LB
(*) Present address: Station Zoologique, 06230
Villefranche-sur-Mer, France
(-) To whom correspondence should be addressed
Arenicola marina is one of the most widely distributed and
important members of intertidal soft sediment communities around
the coast of Britain. In some localities it can be the dominant
organism within the macrofauna; it is an important prey organism
for birds and fishes, and has a major effect in re-working the
sediment. It is also highly prized by sea anglers as bait and
where it is heavily exploited, bait diggers may cause severe
environmental disturbance.
The reproductive biology of A. marina has been of particular
interest for a number of years, and over the past century has
attracted the attention of workers such as Ashworth (1904),
Newell (1948), and Howie (see 1984 for review). However, in spite
of such interest, the widespread distribution and ecological
importance of Arenicola marina, many aspects of its reproduction
are still poorly understood.
Arenicola marina has an annual cycle of reproduction and
most populations around the British coast spawn in late autumn
or early winter. In some localities spawning is highly
synchronised between individuals and is often epidemic. Spawning
is evident by the appearance of sperm puddles on the sediment
surface during periods of low water. Spawned eggs are generally
not observed and these are thought to be retained within the
burrows of the female. The process of spawning is under endocrine
control from the prostomium and in males the endocrine substance
has been termed Sperm Maturation Factor (SMF). SMF stimulates
sperm motility in the body cavity prior to spawning and the
acquisition of motility in the coelomic fluid is a prerequisite
for spawning; immotile spermatozoa are not usually released via
the nephromixia (Howie, 1961).
The work which we have carried out recently has focused on
the endocrine control of both sperm activation and spawning, and
has identified a 20-carbon polyunsaturated fatty acid, 8,11,14
- eicosatrienoic acid, as SMF (Bentley et al., 1990). This fatty
acid is capable of stimulating spawning in sexually mature male
A. marina and spermatozoa are released from the body during
periods of ejaculatory behaviour. These ejaculations are
accompanied by behavioural modifications and this suggests that
spawning is a far more active process than has been considered
by earlier workers. Throughout spawning, ejaculatory behaviour
is interspersed with periods of quiescence, during which sperm
are not released, and this cycle continues until spawning ceases
or the animal is spent.
Quantitative analysis of spawning: the determination of the
number of gametes released into a fixed volume of sea water
during the 24 hours immediately following the injection of SMF,
has demonstrated that there is little intra-individual variation
in the spawning response and all animals release a similar number
of gametes (females release 1-2 x 105 oocytes; males liberate ~2
x 1010 spermatozoa). In addition, if sufficiently sexually
mature, all animals injected with SMF undergo spawning and
usually begin so within 60 minutes. Thus, the variability which
has been observed in other polychaete species (see for example
Olive et al., 1981a & b) does not appear to occur in A. marina.
SMF does not induce spawning in females, although injection of
a crude homogenate of the prostomium is capable of inducing
spawning in female worms. In fact the spawning response in
females is, in many respects, very different to that in males.
Space does not permit a detailed discussion of this here, but it
is clear from the results we have obtained that there are sex
specific differences in the endocrine signalling mechanism of A.
marina.
The work outlined here is of general interest for a number
of reasons. First, because A. marina differs from that of most
other marine invertebrates - in that sperm become motile in the
body cavity prior to spawning - two interesting questions are
raised: how are the spermatozoa 'switched on' ? and how does this
mechanism compare to that of other species ? Some work in these
areas has already been undertaken (Bentley & Pacey, 1991). Also,
because there is an endocrine factor which has a direct action
on sperm function, this system has certain parallels with that
of higher animals, such as mammals, where sperm interact with
seminal fluids prior to ejaculation. In the past, invertebrate
models have provided fundamental information in the understanding
of basic biological questions - e.g. sea urchins have provided
a model for the study of fertilization - and therefore the sperm
activation system of A. marina may have potential use as a model
for sperm function and the interaction of sperm with signalling
molecules.
Secondly, an understanding of the endocrinology and spawning
mechanism allows a degree of control and manipulation of the
reproductive cycle in A. marina. At present, mature gametes can
be obtained, upon demand, from sexually mature individuals and
this has potential uses in the aquaculture of A. marina. The
rearing of animals for commercial purposes as a bait species, or
for 're-seeding' areas where the natural population has been
heavily exploited, now becomes a real possibility.
Finally, because individuals of A. marina at some localities
spawn with a high degree of inter-individual synchronicity and
because this is often highly predictable from year to year, it
is suggested that there may be a strong environmental control
mechanism which underlies reproduction. Work carried out on a
number of polychaete species in recent years has increased our
knowledge of the environmental control of reproduction and how
environmental information may be transduced by the endocrine
system. Clearly, the endocrine mediated sperm activation and
spawning mechanism of A. marina presents an ideal step at which
such environmental control can be regulated. With the
identification of SMF, the endocrine principal involved, then a
detailed investigation of the environmental control of spawning
in this species becomes a real possibility.
References
Ashworth, J.H. (1904). Arenicola, L.M.B.C. Memoirs 11, Liverpool
Marine Biology Committee, University of Liverpool.
Bentley, M.G., Clark, S. & A.A. Pacey (1990). The role of
arachidonic acid and eicosatrienoic acids in the activation of
spermatozoa in Arenicola marina L. (Annelida: Polychaeta) Biol.
Bull. 178: 1 - 9.
Bentley, M.G. & A.A. Pacey (1991). Hormonal control of sperm
activation and spawning in the lugworm Arenicola marina (L.)
(Annelida: Polychaeta). Gen. Comp. Endocrinol. 82: 236.
Newell, G.E. (1948). A contribution to our knowledge of the life
history of Arenicola marina (L.) J. mar. biol. Ass. U.K. 27: 554
- 580.
Howie, D.I.D. (1961). Spawning mechanism in the male lugworm.
Nature 192: 1100 - 1101.
Howie, D.I.D., (1984). The reproductive biology of the lugworm,
Arenicola marina L. In: Polychaete Reproduction. Fortschritte der
Zoologie, Band 29. Fischer, A., & H-D. Pfannenstiel (eds).
Gustav-Fischer-Verlag, Stuttgart, New York. pp. 247 - 263.
Olive, P.J.W., Garwood, P.R. & M.G. Bentley (1981a). Reproductive
failure and oosorption in polychaeta in relation to their
reproductive strategies. Bull. Soc. Zool. Fr. 106 : 189-196.
Olive, P.J.W., Garwood, P.R., Bentley, M.G. & N.H. Wright
(1981b). Reproductive success, relative abundance and population
structure of two species of Nephtys in an estuarine beach. Mar.
biol. 63 : 189-196.
-------------------------------------------
Segment Counting in the genus Nephtys: it's relevance to N.
hombergii
Peter Garwood
8 Lesbury Road, Heaton
Newcastle upon Tyne, NE6 5LB
Introduction
Recent work by Rainer (1989) has made possible a more precise
definition of Nephtys hombergii Savigny, 1818 by reinstating N.
assimilis Örsted, 1843 and raising N. hombergii kersivalensis
McIntosh, 1908 to full specific status. Several studies on
European species of Nephtys have noted the value of the first
setiger to bear inter-ramal cirri (= branchiae) as a taxonomic
character (e.g. Garwood & Olive, 1981; Rainer, 1984,1989, 1990).
In many species, particularly those in which the first
inter-ramal cirrus is close to the anterior end, there is little
or no variation beween individuals but N. hombergii may have
inter-ramal cirri beginning on setigers 4, 5 or occasionally 6.
Nephtys species all tend to a characteristic maximum number of
body segments. The present study reports on the relationship
between total setiger number and the first setiger to bear
inter-ramal cirri in populations of N. hombergii around British
coasts.
Materials and methods
Intertidal specimens were taken at various sites around the coast
of Britain - Wig bay and Monreith, Dumfries and Galloway; Black
Middens at the mouth of the river Tyne; Newton by Sea,
Northumberland; outer Tees estuary; Shoeburyness in the outer
Thames estuary; Gann Flat, Dyfed. Sublittoral specimens
originated from several sites in the North Sea off Northumberland
and Scotland. For each specimen the first setiger to bear
inter-ramal cirri, and, for entire specimens, preserved body
length and total number of setigers were recorded.
Results
Definition of N. hombergii
Parapodial characteristics proved to be the most reliable
ones in separating N. hombergii from other species in the genus.
Using the terminology of Rainer (1989), both acicular lobes have
well developed medial bulbs; both pre-setal lamellae are bilobed,
the ventral lamella having an additional notch just below its
dorsal point of origin; both post-setal lamellae are well
developed, the dorsal one extending well below the tip of the
aciculum and the ventral one being large and somewhat upturned.
The presence of the medial bulbs on the acicular lobes of
anterior segments separated N. hombergii from all other north
European species of the genus, with the exception of N. assimilis
(see Rainer, 1989).
First setiger to bear inter-ramal cirri
The majority of specimens in the samples had inter-ramal
cirri beginning on setiger 4 (referred to as type A) or setiger
5 (type B); only one had inter-ramal cirri from setiger 3 and
five had them from setiger 6 (Table 1). In the majority of
individuals, the first inter-ramal cirri were on the same setiger
on both sides of the body but where the two sides differed, the
more anterior setiger was recorded. Some populations were
dominated by type A individuals, others by type B (these included
the subtidal samples). In the Tees estuary and Gann Flat samples
there were significant proportions of both types.
Relationship between body length and setiger number
On shores dominated by one or other type, type A specimens
tended to have more setigers for a given body length than type
B specimens (Figure 1). Initial growth is largely the result of
segment proliferation but gradually the increase in size of
existing segments contributes more and more to the increase in
body length. Eventually a plateau is reached, so that further
substantial increase in length includes little or no further
segment proliferation. For type A animals this plateau is at
setiger 130-135, whilst for type B it is at 110-115. The
distinction holds true on shores where mixed populations were
found (Figure 2); individuals of >40-50 mm can largely be
separated into types A or B on the basis of setiger number.
Whilst the population at Shoeburyness was dominated by type
B individuals, defined by the position of the inter-ramal cirri,
the sample also included 6 animals referred to type A for which
body length/setiger number data are available. Of these, 3 had
setiger numbers characterstic of type B and are likely to
represent type B animals in which the cirri begin one setiger
further forward than normal; the remaining 3 have much higher
setiger numbers for their body size and are likely to represent
true type A animals (Figure 3). Examination of the three
specimens with inter-ramal cirri from setiger 5 from Wig Bay,
Black Middens and Newton indicate that these are, in terms of
setiger number, type A animals in which the cirri begin one
setiger further back than normal.
Specimens originating from North Sea sublittoral sites,
initially identified as N. hombergii, comprised 3 species: those
with inter-ramal cirri beginning on setiger 4 were either N.
kersivalensis or N. assimilis , the former being commoner among
the specimens examined. Those identified as N. homgergii
according to their parapodial morphology had inter-ramal cirri
from setiger 5, i.e. type B, or, occasionally, from setiger 6.
However, they had more setigers for a given body length than
intertidal type B animals (Figure 4) and were more like
intertidal type A animals in this respect.
Discussion
In the intertidal samples, at least two forms currently
attributable to N. hombergii are recognisable on the basis of
the first setiger to bear inter-ramal cirri and the relationship
between preserved body length and setiger number. Type A have
inter-ramal cirri from setiger 4 and more than 120 setigers at
a body length of 100mm whilst type B have inter-ramal cirri from
setiger 5 and fewer than 120 setigers. There appears to be no
clear geographical distinction between the two types and mixed
populations occur. The consistent correlation between these
characteristics leaves little option but to suggest that the two
types represent distinct species. Which one represents the
species originally described by Savigny remains to be
ascertained.
The limited observations on truly subtidal specimens
indicates that they would belong to type B on the basis of first
setiger to bear inter-ramal cirri and to type A with regard to
the body length/ setiger number relationship. This may be
evidence either for a third 'species' or for an environmental
influence on one of the characteristics used to separate types
A and B in the intertidal zone. At present each option remains
equally likely.
References
Garwood, P.R. & P. J.W. Olive (1981) The significance of the long
chaetal form of Nephtys caeca (Polychaeta: Nephtyidae) and its
relationship to N. longosetosa. Sarsia, 66:195-202.
Rainer, S F. (1984) Nephtys pente sp. nov. (Polychaeta:
Nephtyidae) and a key to Nephtys from northern Europe. J. mar.
biol. Ass. U.K. 64:899-907.
Rainer, S. F. (1989) Redescription of Nephtys assimilis and N.
kersivalensis (Polychaeta: Phyllodocida) and a key to Nephtys
from northern Europe. J. mar. biol. Ass. U.K. 69:875-889.
Rainer, S. F. (1990) The genus Nephtys (Polychaeta: Phyllodocida)
in northern Europe: redescription of N. hystricis and N. incisa.
J. nat. Hist. 24:361-372.
Table 1 FIRST SETIGER TO BEAR INTER-RAMAL CIRRI IN SPECIMENS FROM
SITES AROUND BRITAIN
===========================================================
Setiger number
Site 3 4(A) 5(B) 6 Total
-----------------------------------------------------------
Wig Bay - 13 1 - 14
Monreith - 33 - - 33
Black Middens - 33 1 - 34
Newton - 40 1 - 41
Tees estuary 1 73 37 - 111
Shoeburyness - 17 104 - 121
Gann Flat - 11 14 - 25
North Sea subtidal - - 37 5 42
===========================================================
--------------------------------------------------
Problems in the Identification of Polychaetes for the Purpose of
Benthic Environmental Assessment
Telfer T.C., Woodham A., Hamilton S., and Docherty C.
Environmental Services Unit, Institute of Offshore Engineering,
Old St. James Church, Port Edgar Marina, South Queensferry, West
Lothian EH309SQ
The use of marine benthic community monitoring in assessing the
environmental impact of offshore and onshore industrial
developments is already considerable and is likely to increase
in the forseeable future. As polychaetes typically comprise over
50% of the species and individuals encountered when surveying
such communities the importance of accurate polychaete
identification can be appreciated. This contribution sets out to
present some of the interrelated problems faced in routine
commercial polychaete identification, and to reconcile
differences in aims between this work and polychaete taxonomic
research.
The objective of an environmental survey is to assess
anthropogenic effects on the naturally fluctuating community by
comparison of original "baseline" surveys with subsequent
surveys, or unaffected background communities with test sites.
The various ways of achieving this, including examination of the
presence or absence of sensitive "indicator species", univariate
methods such as diversity and evenness measures, or multivariate
techniques, all require absolute objective data. The first
obstacle encountered is therefore the requirement to put a name
to every single specimen collected, irrespective of age or
condition, above a predetermined size limit (usually 0.5mm).
Keeping this in mind we can begin to consider some of the other
problems routinely faced.
Time
Benthic monitoring studies are usually carried out to a
strict, predetermined timescale imposed by the client before work
begins and the extent of the task can be assessed. Experience of
previous surveys in similar areas can be most valuable when
negotiating deadlines for workup. The time available to spend on
each individual animal is, therefore, very limited and, even
though experienced workers can achieve a high degree of accuracy,
they have little opportunity to research unusual specimens.
Identification of incomplete, damaged or unfamiliar individuals
may have to be left at a higher systematic level than would be
possible given more time.
Specialisation
Most people involved in such work are usually able and
expected to identify all families in their chosen group, whether
polychaetes, molluscs or crustaceans, to the same degree of
accuracy rather than specialising in selected families. As the
Polychaeta are such a major component of the fauna this
represents a large area of expertise to be mastered. Occasionally
an individual identifier may work up all phyla in a survey,
although this is unusual.
Standardisation
Comparison of results between surveys requires
reproducibility ie. standardisation of identification. This
applies not only between people, whether working in the same or
different organisations, but also from year to year. This has
been difficult to achieve in the past but the adoption of a
mutually agreed checklist such as that attempted by the Marine
Conservation Society ( Howson, 1987), would solve many problems
regarding the assignation of only currently accepted
nomenclature. The establishment of inhouse checklists on database
has already been achieved by several organisations independantly
but a standard definitive list is not yet available. Drawbacks
inherant in this concept include the inflexibility imposed by the
system on naming new or unfamiliar animals, and the fact that,
as updating has to be done at sensible intervals rather than as
soon as a new animal is described or genus revised, the list is
always behind current knowledge.
Literature
This is the point at which the work of the polychaete
taxonomist and the commercial identifier meet. Routine
identification relies totally on the dedicated efforts of a small
number of taxonomic enthusiasts, past and present, professional
and amateur, from all around the world. Thus it is understandable
that the available literature takes many forms, varying in
content, format, language etc., and targets the different
families unequally. Finding one's way around presents another
daunting problem to the identifier, especially when just
learning. Although descriptions of new species or revisions of
existing ones satisfy the criteria of taxonomy, they can be
difficult and time consuming to assimilate, and impossible to
apply to the incomplete, immature or damaged specimen in the
dish.
As survey work of this nature is likely to become
increasingly in demand in the current atmosphere of high public
and industrial environmental awareness, identifiers and
taxonomists have an unprecedented chance to complement and
enhance each others efforts. Indeed, there is already a
considerable overlap of interest, with several workers involved
in both spheres of activity.
The taxonomists, having already spent the time and
groundwork required to research a new species or review a genus,
could prepare a simple key, written synopsis or illustrations
aimed at the identifier. These would be based on obvious features
that do not become detached easily (elytra, cirri, gills), are
not sex specific (genital spines), and do not rely on colour
(most benthic samples are stained red with Rose Bengal to assist
sorting), size, or special preparation. A range of usable
features should be given wherever possible. The overriding
criterion to satisfy is to enable an identifier with an assumed
amount of general polychaete experience to put an accurate name
to every specimen in their sample, regardless of its condition,
in a short space of time. Although this is obviously Utopian the
situation as it stands could be improved upon fairly easily by
cooperation. Standardisation could be ensured by the publication
of periodically updated checklists citing recommended keys for
each family which incorporate all accepted species.
In return, the identifier is able to supply the taxonomist
with a very large range of specimens as required, once permission
of the client is obtained. They can also argue the case for the
continuation of such research and lobby support for its increased
financing, especially from sources outwith those traditionally
supportive of pure research such as government funded
Universities and museums. Many taxonomists are part-time or
completely unfunded yet identifiers rely on their work. As the
need for environmental protection grows those of us in the market
place can put a strong argument to industry for increased
financial support for the taxonomic basis on which we all depend.
Reference
Howson, C.M. (ed) (1987) Directory of the British marine fauna
and flora. A coded checklist of the marine fauna and flora of the
British Isles and its surrounding seas. Marine Conservation
Society. 471pp.
-----------------------------------------------
A Review of the Northern European Species of Pholoe Johnston
(Polychaeta: Pholoidae)
Mary E. Petersen
Zoological Museum
University of Copenhagen
Universitetsparken 15, DK-2100
Copenhagen
Denmark
Species of Pholoe are dominant constituents of much northern
European benthos, but their potential value as indicator species
remains unknown because most authors ignore or overlook specific
differences and continue to identify all oculate species as P.
minuta, a western Atlantic species not known to occur in the
eastern Atlantic. Similarly, most recent authors have not
recognised the eastern Atlantic P. inornata Johnston, which has
not yet been seen in material from the western Atlantic or
southwest Greenland, the type locality of P. minuta.
Four species (P. inornata, P. baltica Örsted, P. assimilis
Örsted and the blind P. pallida Chambers) are common in nearshore
waters, and a fifth (P. fauveli Kirkegaard) is known from deeper
waters in the Bay of Biscay and off the Faroes.
The paper commented on the identity of P. longa (O.F.
Müller), P. minuta (Fabricius), and P. synophthalmica Claparède
and the known distributions of these and few other species.
----------------------------------------------------
Analytical Intercomparison
Exercises in Marine Benthic Biology
Derek C Moore (+) and Mike Elliott
(+) Marine Laboratory
PO Box 101, Victoria Road
Aberdeen
In 1988 a Biology Task Team, composed of benthologists from
throughout the UK, was convened by the Co-ordinating Group on
Monotoring Sewage Sludge Disposal sites (CGMSD). Its remit was
to review approaches to field monotoring of benthic fauna. As a
result of the Task Team's deliberations, a Scottish Fisheries
Information Pamphlet was published in 1990 which laid down agreed
strategies and methods for sampling and analysing benthic
communities on sludge dump sites. The publication also
investigated the potential of various univariate and multivariate
statistical methods for use in setting Environmental Quality
Standards (EQS).
Many of the proposed standards depended on relative
percentage deviation from a 'normal' value obtained from a
control site. If this type of EQS were to be adopted nationwide
then the variability attributed to the processing laboratory
might add a significant amount to the natural variability. In
order to investigate this, an intercalibration exercise was
initiated by the Task Team in which 11 laboratories, representing
Government Departments, River Purification Boards, Universities
and commercial laboratories, participated. (The paper discussed
the results of the exercise and the implications for EQS setting
using benthic community data both at the species level and at the
family level).
-------------------------------------------------
Distribution and Population Studies on Myzostoma cirriferum
(Myzostomida) in a Scottish Sea Loch
Annette Woodham
Environmental Service Unit
Institute of Offshore Engineering
Old St. James Church, Port Edgar
South Queensferry
West Lothian, EH30 9SQ
Samples of Antedon bifida (Pennant), the only commonly occurring
British shallow water crinoid, were collected individually during
a study of Myzostoma cirriferum Leuckart in a Scottish sea loch.
The data were used to determine the incidence of infestation and
to establish the symbiont's population size and structure over
a twelve-month period. A very extended reproductive season
results in early post-larval stages, which first appear on the
host in October at a length of approximately 50mm, being present
for most of the year. Settlement is greater in the deeper parts
of the range, and juveniles dominate the population numerically
between November and May. Abundance is high during the summer
with up to 3000 fully grown individuals occurring on a single
host and 100% of the Antedon infested. During the late autumn,
counts fall to less than 10 per host and the incidence of
infestation, showing a positive correlation with depth, drops to
about 50% in shallow water. Size of Myzostoma is independent of
host size, but positive correlations are shown between size of
Antedon and mean number of Myzostoma supported. Depth and season
are, however, more important than host size in determining the
levels of infestation of individual crinoids.
In Press: Proceedings of the 25th European Marine Biology
Symposium.
----------------------------------------------
Spirorbid Distribution, including a New Madeiran Subgenus
Phyllis and Wyn Knight-Jones
University of Wales, Swansea
Most Spirorbidae (about 70 species out of 108, including 12 out
of 14 species of Spirorbis) seem to be confined to one ocean, yet
at least twenty species are circumglobal. Ten circumpolar species
extend into neighbouring oceans, including three Paralaeospira,
two Circeis a Bushiella and a Jugaria in the north and a
Paralaeospira, a Protolaeospira and a Romanchella in the south.
More remarkably, at least ten thermophilic species are also
circumglobal. Leodora (monotypic?) is known only from the
tropics, including Sri Lanka, West Indies, Hawaii and NE
Australia. The other nine, which are more subtropical, comprise
ten Spirorbis, a Janua, two Neodexiospira, two Pileolaria, a
Simplaria and a Vanearia. These provide most of the species in
the spirorbid fauna of the Canary Islands. Madeiran spirorbids
are similar, but also include a new species very close to
Spirorbissensu stricto except that its collar folds are fused
dorsally to form a tunnel over the faecal groove. Such tunnels
are also formed in Neodexiospira, Romanchella and the serpulid
Ficopomatus uschakovi. The recurrent gut of Caobangia
(Caobangiidae) perhaps results from a similar process.
--------------------------------------------------
Use of Methyl Green Staining in Identification
Lynda Warren
Cardiff Law School
University of Wales College of Cardiff
Cardiff
Capitellids are notoriously difficult to identify because (1)
they show a general lack of distinctive features, (2) those that
they do have, change with age and not necessarily sexual maturity
and (3) they are frequently found fragmented in samples. At the
first International Polychaete Conference, Ewing claimed to be
able to distinguish between Mediomastus ambiseta and M.
californiensis in mixed samples from the Gulf of Mexico by
staining the worms with methyl green stain.
Together with Pat Hutchings, of the Australian Museum, I
have been working on a review of the genus Mediomastus. We have
had great difficulty devising a practicable key for the
identification of species and I decided to test for methyl green
staining. The results were both surprising and confusing.
The first point to note is that the technique is not
suitable for large worms, ie anything bigger than a small M.
fragilis. This is because the staining patterns are only apparent
when the light passes through the worms. With thicker worms, the
light is reflected and the pattern is much more difficult to
detect.
The second point to note is that there was considerable
variation between samples. I was able to repeat the staining
pattern obtained by Ewing for worms from the same area but other
specimens, apparently of the same two species gave different
patterns. This could mean that the stain varies with some
physiological characteristic or with preservation or it could
mean that the worms were misidentified. I also noted that
specimens of some other species gave different staining patterns
completely unlike those shown by most Mediomastus in terms of
pattern and colour.
In order to examine this problem further I have extended my
coverage to other species of capitellid. Some specimens give very
clear results, consistent within a sample, while others are as
confusing as Mediomastus. One of the difficulties with this type
of work is that I do not know the history of the specimens. I
have carried out some preliminary experiments on a population of
Capitella capitata and hope to encourage other workers to carry
out similar investigations.
------------------------------------------------
North Atlantic Polychaetes in Photographs (poster)
Kathie Atkinson (-) and Chris Mettam (*)
(-) 38 Mona Vale Road, Pymble 2073, Australia
(*) School of Pure and Applied Biology, University of Wales
College of Cardiff, Cardiff CF1 3TL
Many attractive and often distinctive features of polychaetes are
lost with preservation and need to be recorded photographically
while the animal is alive and healthy. One thinks of Fauvel's
frequent but frustratingly inadequate description "coloration
dans alcool - blanc jaunâtre". High speed flash photographs of
polychaetes record aspects of both the appearance and behaviour
of the living worms, particularly in swimming and burrowing.
---------------------------------------------------
Intradermic Penetration of Sperm Cells in Myzostoma cirriferum
(Annelida, Myzostomida)
Igor Eeckhaut and Michel Jangoux
Laboratoire de Biologie Marine; Université de Mons-Hainaut, 19,
Av. Maistriau, 7000 Mons, Belgium
Myzostomids have a very strange and interesting mode of
reproduction: the so-called hypodermic injection by means of
spermatophores. It implies the emission of a spermatophore from
a donor myzostomid to the integument of a receiver. Thanks to in
vivo observations and microscopic (photonic and electronic)
techniques we have described the structure of mature
spermatophores and have deciphered the different phases of the
intradermal penetration of the spermatophore content.
The emitted spermatophore is a white V-shaped structure of
5OOmm long. According to its contents, three spermatophoral
regions can be distinguished: the body with the horns, the foot
and the basal disk. The body with the horns includes the
spermiocytes, each formed by one cyst-cell containing numerous
spermatozoans. The foot includes podocysts, each formed by one
to three small podocytes while the basal disk includes numerous
vesicles.
The vesicles of the basal disk are the first in contact with
the cuticle of the receiver myzostomid. The material they include
is supposed to have a histolytic action and to be responsible for
the lysis of the cuticle and epidermal cells, providing passage
for the spermatophore contents. Afterwards, cysts move thanks to
the spermatozoons' beatings and pass through the receivers
integument. At the time of penetration, cytoplasmic membranes of
cyst cells merge together forming an enormous syncytium extending
into the whole receiver's body. The whole process of the
intradermic penetration (i.e. from the fixation of the
spermatophore to its reduction to an empty matrix) lasts from one
to five hours.
-----------------------------------------------------
Research Request
Tube-living larvae of Terebellidae
Our recent work with polychaete larvae (after the extensive work
of Bhaud & Cazaux in Oceanis 13 (6): 596-753 ) at the marine
laboratories of Arcachon and Banyuls-sur-mer, has revealed the
presence of three different types of terebellid aulophore larvae,
belonging to the genera Lanice and Loimia. The term aulophore
refers to planktonic larvae bearing a tube. At present, from the
literature, there are about 28 species belonging to the two named
genera, but little is known about their larval stages. We should
be very interested in receiving any of these aulophore larvae
from different geographic areas to complete our studies. An
illustration of four different aulophore larvae is included here.
The animals (better preserved in alcohol) can be sent to :
G. Marcano
Institut Universitaire de Biologie Marine, F-33120 Arcachon,
France.
Collectors sending valuable specimens for observation (by
compound microscope or SEM) will be associated with the
publication.
------------------------------------------------------
Systematic Biology in the United Kingdom - A Progress Report
Chris Mettam
Readers of the Polychaete Research Newsletter may be interested
to know what outcome, if any, has occurred as a result of the
enquiry recently instituted into the state of systematic biology
in the United Kingdom. There is some positive encouragement to
report.
After receiving a large body of anecdotal evidence and
opinion(1) concerning the decline of systematic biology research
and teaching in the UK, the House of Lords Select Committee on
Science and Technology sought corroborative, quantitative
information on expenditure, sources of funding and involvement
of manpower in biological systematics in the UK as a basis for
recommendations which will be debated in the House later this
year. The report(2) containing these recommendations is now
published and offers proposals to stem the decline in systematic
biology may be stemmed. Many of the points set out in the
submission from the Polychaete Society (Polychaete Research
Newsletter 13, 1991) have been accepted by the Select Committee
so in our small way we may have influenced the affairs of lords
and helped to sustain systematic biology for the future.
The report acknowledges the central importance of systematic
biology to theoretical and applied branches of biological science
and recognises that a combination of circumstances has placed at
risk "the research itself, the curation of the collections and
its position at the universities" to the national detriment. The
report's recommendations include explicit financial support. They
are that core funding at major national systematics institutions,
which comes from Government sources, should be maintained in real
terms after a decade of decline; the Advisory Board for Research
Councils should establish a fund of £1m per annum for five years
exclusively to support systematic biology, should also assess the
need for training in systematics and fund appropriate M.Sc
courses; the Office of Arts and Libraries (funding agent for the
Natural History Museum, London) should set up a panel of
scientific advisers and establish a rolling programme of up to
£0.5m per year to assist systematic collections of research
potential outside 'grant-in-aid institutions'; that major
systematics institutions should establish a forum, akin to the
Dutch National Plan for Systematics and Evolutionary Biology, to
rationalise their holdings and areas of special expertise. After
the five year boost of funds from the ABRC, it is rather
optimistically hoped that the systematic biology can stand as an
equal to other research areas which have increasingly squeezed
systematics from the teaching and research agenda.
There are recommendations to stimulate closer research and
training contacts between museums and universities. Museum folk
will welcome support for a basic minimum standard of curation (no
"important" collection should be without regular attention from
a contracted curatorial officer) and removal of anomalies in the
opportunities for funding research (at present the Natural
History Museum is the only museum institution with any chance of
obtaining research council grants). University researchers will
welcome a lifeline for classical systematics before its current
aging and declining population of practitioners reach retirement.
Overall this is encouraging although limited. Systematics
is seen as in need of a stimulus when it really needs a life
support system. The proposals contained in the report are
unlikely to lead to a free flow of research grants or
studentships and there is still only slim hope of of success for
research proposals unless they are strongly 'hypothesis-based'
or linked to developments and new applications of modern methods.
Beyond its own recommendations for a financial fillip, the
Committee points to future opportunities from the EC and world
bank Global Environment Facility, especially in relation to
global conservation programmes where biodiversity is seen to be
a key issue. Now it is up to all UK systematic biologists who
have not yet slipped into their dotage to take advantage of a
brief period of positive discrimination for systematics biology,
should it come about, and to demonstrate that a little money
really can go a long way in this most basic of sciences.
(1). Select Committee on Science and Technology. Systematic
Biology Research, written evidence received up to 21 May 1991.
House of lords Paper 4I, London: HMSO (1991),106pp.
(2). Select Committee on Science and Technology. Systematic
Biology Research, Volume 1 - report. House of lords Paper 22-I,
London: HMSO (1992),106pp.
----------------------------------------------------
D.P. Wilson
Dr. D.P. Wilson died suddenly at the age of 89 years on December
20th 1991. He will be remembered as a pioneering photographer and
researcher with a particular interest in polychaetes. His
photographs decorate and illuminate many popular books on marine
life and for many will have been a first introduction to the
world of living plankton.
In a long period of research at the Marine Biological
Association, Plymouth, from his arrival as a student in 1926 and
his appointment to the staff in1928, 'D.P'. made many studies of
polychaetes. Initially in studies of larval development, later
in habitat selection and larval settlement behaviour, he set in
train a number of research lines that are still bearing
productive results today. Yves Gruet recalls happy visits and
long correspondence with him over their joint enthusiasm for
Sabellaria.
CM
------------------------------------------
Arctic Polychaeta
Igor A Jirkov
Department of Hydrobiology, Moscow State University, Moscow,
119899, CIS
A guide to Polychaeta of the North Polar basin (from the Bering
Strait to the Faroes, Shetlands and Iceland) is in preparation.
It is based on original material, mainly from Soviet collections.
The format will be:
1. brief description of each family
2. key for identification of genera and species
3. short description of each genus, indicating types species
and type locality
4. description of each species including (a) drawing of
species, (b) brief synonomy (first description, important
changes of name, works with good pictures and descriptions),
(c) main morphological features, (d) distribution in the
world's oceans, general biogeographic characteristic and
distribution within the Arctic Ocean, (e) ecology, (f)
material investigated,(g) map of Arctic and world
distribution.
As you can see, there are several families not currently in
preparation; this is because I cannot find polychaetologists for
them. It seems that such a guide would be useful for all of us,
so if somebody can be found through the Polychaete Research
Newsletter, it would be to our mutual benefit.
--------------------------------------------------
List of families and preliminary list of authors, 25 March 1991
1. Phyllodocidae following P. V. Uschakov
2. Tomopteridae following P. V. Uschakov
3. Typhloscolecidae following P. V. Uschakov
4. Alciopidae following P. V. Uschakov
5. Aphroditidae I. Jirkov
6. Polynoidae
6a. Macellicephalinae R. Ya Levenstein
7. Sigalionidae
7a. Pholoe ?M.E. Petersen
8. Acoetidae following M. Pettibone
9. Chrysopetalidae ? G.N. Buzhinskaja
10 Glyceridae I. Jirkov & ? G.N. Buzhinskaja
11. Goniadidae I. Jirkov
12. Nereidae V.V. Chlebovitch
13. Syllidae
14. Hesionidae
15. Calamyzidae A. Tzetlin
16. Pilargidae T Britaev
17. Nephtyidae I. Jirkov
18. Sphaerodoridae A. Ozolinsh
19 Euphrosinidae J. Kudenov
20. Amphinomidae J. Kudenov
21. Spintheridae S. Potin
22. Eunicidae I. Jirkov
23. Onuphidae N. Kucheric & I. Jirkov
24. Dorvilleidae A. Tzetlin
25. Arabellidae
26. Lumbrineridae
27. Trochochaetidae ? G.N. Buzhinskaja
28. Poecilochaetidae
29. Apistobranchidae A. Tzetlin
30. Spionidae A. Sikorski
30a. Polydorinae V. Rhadashevski
31. Chaetopteridae ?M.E. Petersen
32. Cirratulidae ?M.E. Petersen
33. Magelonidae
34. Cossuridae
35. Fauveleopsidae
36. Flabelligeridae I. Jirkov
37. Acrocirridae
38. Scalebregmatidae J. Kudenov
39. Orbiniidae
40. Paraonidae
41. Opheliidae
42. Capitellidae
43. Arenicolidae
44. Maldanidae N. Detrinova
45. Sternapsidae
46. Oweniidae ?I. Jirkov
47. Sabellariidae I. Jirkov
48. Pectinariidae I. Jirkov
49. Ampharetidae I. Jirkov
50. Terebellidae I. Jirkov & M. Safronova
51. Sabellidae I. Jirkov & E. Kuprianova
52. Serpulidae I. Jirkov & E. Kuprianova
53. Spirorbidae A Rhavaski
------------------------------------------------------
BOOK REVIEWS
Polychaetes from Scottish waters : A guide to identification
Part 3 Family Nereidae
Susan Chambers & Peter Garwood
1992, National Museums of Scotland
66pp. £12.50;
ISBN 0-948636-29-7
This guide, in the format of previous volumes (on scale-worms)
in the same series, provides a means of identification of adult
nereids known or expected to occur in Scottish waters. The
authors exceed their stated purpose to provide identification for
10 species and actually include a key to 11, namely Ceratocephale
loveni, Nereis diversicolor, N. fucata, N. irrorata, N.
longissima, N. pelagica, N. virens, N. zonata, Perinereis
cultrifera, Platynereis dumerilii, Websterinereis glauca . A
further list comprises 13 species given as UK records of
"uncertain status" which cries out for a little further
elaboration, not least to have generic names identified in full
rather than by initial letter. The list includes Nereis succinea
but omits a number of species such as sibling species Nereis
grandis , N. kergurelensis and N. southerni , which are
discussed under N. virens sensu lato. The full list of species
covered is only available in an Index to genera and species on
the final page of text. The indexing, however, is not complete
and does not tell us that Platynereis coccinea is discussed
under P. dumerilii, where its known UK records are mentioned, and
appears again in a drawing (as an additional record but with a
question mark) in a useful figure comparing the pharynges of all
species.
Descriptions and keys use morphological features based on
examination of named collections and illustrated from identified
museum specimens. The authors' perspective is entirely that of
the museum worker, not the field naturalist. Species descriptions
exclude colour as it is "not a useful character in preserved
material", so even the obvious and characteristic longitudinal
stripes of N. fucata are ignored - you can only pick up an
obscure clue by noting that it has the synonym N. bilineata .
However, as compensation for this regrettable omission, separate
dichotomous keys enable identification from specimens with
proboscis either everted or withdrawn (a distinct advantage this)
and features referred to in the keys are conveniently arrowed in
a generous supply of integrated figures.
The authors have produced a guide which appears easy to use.
The taxonomy is simplified by containing Hediste and Neanthes
within the genus Nereis and including several morphological and
biological variants within the 11 species that they describe in
detail. These decisions are justified on the basis of their own
original observations on morphological variability in their
specimens and they point out instances where further observations
are needed, so stimulating an active response from the user of
the guide. The choice of the less complicated family name
(Nereidae not Nereididae) is also an agreeable one. One might
question whether the limitation to Scottish waters is too
parochial and arbitrary but having a limited collection of
specimens to examine has enabled the authors to complete this
account relatively quickly and at a reasonably affordable price
C. Mettam
----------------------------------------------
The Marine Fauna of the British Isles and north-west Europe:
Volume I: Introduction and Protozoans to Arthropods,
666pp, 200 figs,
ISBN 0-19-857356-1
£95.00; hardbk
Volume II: Molluscs to Chordates
352pp, 100 figs;
ISBN 0-19-857515-7
£85.00; hardbk.
1990, Clarendon Press
Edited by PJ Hayward & JS Ryland
Every British marine biologist will want this pair of
large-format volumes for their extensive coverage and excellent
line drawings of commoner species of the marine fauna, with keys
based on its specialist authors' many years of practical
experience. They are an excellent systematic introduction to
the rich diversity of inshore life, set at a standard somewhere
between Collins Guide to the Seashore (J Barratt and C. M.
Yonge, 1958) and the Linnean Society Synopses series. Sadly, the
price is beyond the means of any student and all but the most
wealthy amateur or professional. My impressions given here are
based on a brief loan of the books!
I see the greatest benefit of these books in support of
undergraduate field courses, in a training context. Inevitably
what is included is only a sample of the species to be found and
different groups are given unequal treatment. On the other hand
you will find gathered here a convenient source of illustration
and information on such diverse groups as hemichordates, leeches
and beach flies for which it is difficult to find comparable
information elsewhere.
Selectivity has hit the worms particularly hard:
turbellarians and nematodes are only briefly mentioned;
oligochaetes seem to be grudgingly included. Polychaetes get a
fuller treatment with a brisk introduction which uses a minimum
of technical terms - 'gills' instead of 'branchiae' (but
'branchial' is used later as an adjective); 'chaetae' not 'setae'
- and tips for beginners ('notopod' contains the letters 'top'
as a reminder of its position). The dichotomous keys are well
laid out and not daunting. Polychaete families are considered
in alphabetical order but some important ones, eg Paraonidae, are
missing. The authors declare their debt to Fauvel in the species
descriptions and the same source is the inspiration for too many
of the figures, supplemented by illustrations derived from
McIntosh's classic Ray Society monographs. The original drawings
(e.g. Sabellariidae, Sabellidae, Serpulidae and Spirorbidae)
bring a welcome freshness to the pages. I noticed some
misleading remarks such as: "Magelona mirabilis is the only
species in northern Europe"; the family Nephtyidae has "a
flattened body"; formalin vapour is "unpleasant (perhaps even
dangerous)."
The volumes are unique in the English language and no marine
field course should be without them. The main problem with their
use by student groups is that the division into 2 volumes allows
access by only two users simultaneously; it would have been
better to have produced each chapter as a separately bound
section, in the way that magazines are often marketed, so that
each section could be used independently . In practice,
frequently used sections will probably find their way onto the
laboratory bench in this way as photocopies (the line drawings
lend themselves to this treatment) and the precious original
volumes can stay safely protected on the library shelf.
C. Mettam
--------------------------------------------------------
Recent Polychaete Literature:
Publications received and noticed
From the Bulletin of Zoological Nomenclature
Comments on the proposed conservation of the generic name
Myriochele Malmgren, 1867 (Annelida, Polychaeta). BZN 47(2) 1990
pp 124 et sec. Support for conservation of names Myriochele and
oculata (see Case 2554, BZN 46, 229-232).
Comments on the proposed conservation of the specific names of
Ahphrodita imbricata Linnaeus, 1767 (currently Harmothoe
imbricata) and Aphrodita minuta Fabricius, 1780 (currently Pholoe
minuta)(Annelida, Polychaeta). BZN 47(3) 1990, pp 207-210 (see
Case 2452, BZN 46, 22-24)
(1) Mary E. Petersen suggests only conditional suppression of
lepidota as a name which might be applied to some form currently
referred to H. imbricata.
(2) Susan Chambers and David Heppell argue for total suppression
of lepidota which has priority over imbricata but the name
applied to an atypical form.
Basford, D., Eleftheriou, A. & Raffaelli, D. 1990. The infauna
and epifauna of the northern North Sea. Netherlands Journal of
Sea Research 25 (1/2), 165-173.
Ben-Eliahu, M.N., Golani, D. & Ben-Tuvia, A. 1991. On predation
by goatfishes (Mullidae) with new polychaete records for the
Mediterranean coast of Israel and the Gulf of Elat. Isr. J. Zool.
36, 41-42.
Species taken from guts of 5 species of goatfish included new
records and species presumed to be rare in the area: Harmothoe
antilops, Lumbrineris paradoxa, Cirrophorus furcatus , Aricidea
psuedannae, Sigambra tentaculata, Leonates persica, Eone
nordmanni, Lumbrineris emandibulata mabiti, Cirrophorus
branchiatus, Lumbrineris meteorana and Hyalinoecia brementi.
There was little overlap in polychaete prey species taken by
different fish predators, in contrast to results for crustacean
prey.
Ben-Eliahu, M.N. & Ten Hove, H.A. 1991. Serpulid tubeworms
(Annelida, Polychaeta)- a recent expedition along the
Mediterranean coast of Israel finds new population buildups of
Lessepsian migrant species. Isr. J. Zool. 37, 179-180.
22 taxa were collected by SCUBA. New records were Rhodopsis
pulsilla, Semivermilia crenata and Lessepsian migrants Hydroides
minax and Pomatoleios kraussii. Other migrants were Hydroides
heterocercus, H. homocercus, H. operculatus, Spirobranchus
tetraceros. Another Hydroides sp(cf brachyacanthus) is being
studied. Lessepsian serpulids were more common than in the last
census. The distinctive H.minax has become very abundant.
Brey, T. 1991. The relative significance of biological and
physical disturbance: an example from intertidal and subtidal
sandy bottom communities. ECSS 33, 339-360.
Macrobenthos from Arenicola cast, funnel and control samples was
compared and significant differences interpreted. Funnels and
casts have reduced populations of some polychaetes but the
picture is complicated bylocational and seasonal effects and
frequent change in position of both cast and funnel. Among faunal
groupings for multivariate tests fauna were motile polychaetes
(including oligochaetes)"(!)
Broom, M.J., Davies, J., Hutchings, B. & Halcrow, W. 1991.
Environmental Assessment of the effects of polluting discharges:
stage I: developing a post-facto baseline, Estuarine Coastal and
Shelf Science 33, 71-87.
Classification of faunal samples in the Severn estuary, U.K.
defined 10 groups of sites with different combinations of mean
characteristics of elevation, sediment particle size distribution
and redox level. Fine sediments with only a thin oxygenated layer
were characterised by Nephtys hombergi and Tubificoides brownae
with either Tharyx marioni ('sublittoral') or Tubificoides
amplivasatus ('low intertidal') and may be related to local
sewage discharge (146000 m3 per day).
Capaccioni, R & San Martín, G. 1989-90. Pionosyllis anophthalma
n. sp., a new Syllidae (Polychaeta) from the Spanish
Mediterranean coasts. Oebalia XVI, 41-48.
From Cymodocea meadows at Tarragona. Differs from other eyeless
species by presence of long spinigers, dorsal bidentate setae and
falcigers with double curvature.
Eibye-Jacobsen, D. 1991. Observations on setal morphology in the
Phyllodocidae (Polychaeta: Annelida) with some taxonomic
considerations. Bulletin of marine Science, 48(2), 530-543.
Subtle differences in structure exist, especially the distal
portion of the setal shaft, too fine for ordinary light
microscope resolution. They may be useful in defining genera and
a division of Eulalia into 2 genera is anticipated.
Eibye-Jacobsen, D. 1991. A revision of Eumida Malmgren, 1865
(Polychaeta: Phyllodocidae). Steenstrupia, 17(3), 81-140.
Generic diagnosis and key to 21 species, including 4 new species,
are given. Pirakia and Vitiaziphyllum are considered subgenera.
A complete list of synonyms is available from the author.
HARRIS, T. 1991a. The occurrence of Ophelia bicornis (Polychaeta)
in and near the estuary of the River Exe, Devon.JMBA 71, 391-402.
At its most northerly, and only British, recorded site, O.
bicornis is of A type, having gills from setiger 11. It was most
abundant in well-drained, well-sorted sand with negligible
organic solids, inimical to most other fauna but associated with
sporadic Nerine cirratulus and very infrequent Haustorius
arenarius
HARRIS, T. 1991b The rectal organ of Ophelia bicornis Savigny
(Polychaeta): a device for efficient defaecation. Zoological
Journal Linnean Society 103, 197-206.
Defaecation of compacted sand is aided by eversible, rectal,
ciliated fields and muscular papillae which flick out individual
sand grains - an anti-constipation device.
HAVARD, M.S.C. 1991. Temporal changes in trace metal levels in
the polyuchaete Nereis diversicolor O.F. Müller from two British
estuaries wiht contrasting sedimentary metal concentrations.pp
323-327. In , Estuaries and coasts: spatial and temporal
intercomparisons, ECSA 19 symposium (ed. M Elliot & J-P Ducotroy)
Olson & Olson.
Metal concentrations were 2-3 times greater in Severn estuary
sediments than Axe estuary sediments and 2 times greater in worms
than sediments. Seasonal trends were not found. Little of the
variation of metal levels in worm tissue was related to body size
or maturation of gametes.
Jirkov, I.A. 1986. Analysis of taxonomical features of the genus
Samythella (Polychaeta, Anpharetidae). Zool Zh. 65, 325-13.
Geographic variation in 468 specimens of Samythella Verril, 1873
shows S. elongata Verrill, 1873, S. bathycola Ushakov, 1950, S
. pala Fauchald, 1972, S . interrupta Fauchald, 1972, S. neglecta
Wollebaek, 1912 and Eusamathya pacifica McIntosh, 1885 are
synonyms. Eusamathya (type sp E. pacifica) is a junior synonym
of Samythella.
A.V Sikorski, I.A . Jirkov & A.B. Tsetlin. 1988. The genus
Laonice (Polychaeta, Spionidae) within the Arctic Ocean:
weighting the taxonomic characters and species composition. Zool
Zh. 67, 826-838. (in Russian- summary based on a tranlation by
Igor Jirkov)
Three morphotypes are fully described and may be distinguished
on polymorphism of prostomium and peristomium (furrow, eyes) and
neuropodial hooded hooks. Other characters: length of nuchal
tracts; number of branchiae; form of neuropodial hooded hooks;
starting setiger for genital pouches, hooded hooks, inferior
capillaries (which Söderström called 'neuropodiale ventrale
haarborsten') may be useful in separating species but are
dependent on size of the worm (Tables are given). Size is
measured as width between parapodia of setiger 7.
Morphotype 1 (346 specimens) is L. cirrata Söderström, 1920. It
differs from Söderström's account in having 3-5 dentate hooks,
not 2, but these are variable; genital pouches develop gradually.
Prostomium is joined to the peristomium; 2 eyes. Widely
distributed in the Arctic, 7.8 to 1200m depth.
Morphotype 2 (10 specimens) is L. sarsi Söderström, 1920. The
prostomium is almost completely separated but its frontal corners
join with a thin membrane to the ventral surface of the
peristomium; 2 eyes; hooded hooks bidentate.
Morphotype 3 (24 specimens) is a new species described as L.
blakei Sikorski & Jirkov. It differs from all others by more
teeth (8) in hooded hooks. Genital pouches start on setiger 3;
the prostomium is fully separated from the peristomium; no eyes.
Distribution probably Arctic and Atlantic slope 960-2510m depth.
L. bahusiensis Söderström, 1920 is a synonym of L. cirrata. L.
annenkovae Zachs, 1925 is a junior synonym of Marenzellaria
wireni Augener, 1913. Redescribed. Laonice appelloefi Söderström,
1920 is a good species (reviewed by Fauvel 1927) but not present
in this material.
Jirkov, I.A. & Ermolaev, I.G. 1989. Analysis of variation in
taxonomic characters in the genus Nothria (Polychaeta,
Onuphidae). Zool Zh, 68, 5-13. (in Russian- summary based on a
tranlation by Igor Jirkov)
252 specimens from Arctic Ocean, esp. from Norwegian Sea (type
location of N. conchelega, N. hyperborea and N. brittanica), were
examined for variation in those characters visible under the
dissecting microscope, including size (distance between external
margins of ventral cirri on setiger 10). A further 478 specimens
were examined for the starting setiger of branchiae.
2 morphotypes were recognised and are considered separate
species. They cannot be reconciled with Fauchald's 1982 revision.
Nothria hyperborea (Hansen, 1878) has unidentate subacicular
hooks (rarely with small extra teeth) on setiger 1; simple and
pectinate chaetae on setiger 2; branchiae start from setiger
11-15. N. occidentalis is similar but branchiae start on setiger
8.
N. atlantica (Hartman, 1965) has bidentate subacicular hooks on
setiger 1; simple and pectinate chaetae occur on setiger 3;
branchiae start from setiger 9-11 regardless of size of the worm.
N. hawaiensis (=N. mannarensis) is similar but lacks subacicular
hooks on setiger 3.
The types of N. brittanica may be a mix of both morphotypes.
Comparison of characters of other nominal species suggests N.
occidentalis, N. hawaiensis , N. solenotecton, N. abyssia are
distinct species.
Jirkov, I.A. 1989. Bottom fauna of the USSR. Polychaeta. Moscow
State Univ. Press, 141 pp (in Russian).
Mackie, A.S.Y. 1991. Scalibregma celticum new species
(Polychaeta: Scalibregmatidae) from Europe, with a redescription
of Scalibregma inflatum Rathme, 1843 and comments on the genus
Sclerobregma Hartman, 1965. Bulletin of Marine Science 48(2),
268-276.
S. celticum is a smaller species than S. inflatum differing in
possessing eyes (obscured by a peristomial hood), form of
peristomium, mouth and tesselations on the dorsum. Its known
distribution is off Wales, Scotland and France.
Núñez J. & San Martín, G. 1991. Two new species of Syllidae
(Polychaeta) from Tenerife (Canary Islands, Spain) Bulletin of
Marine Science 48(2) 236-241
Pionosyllis dionisi and Sullis cruzi are described and compared
with similar species.
Ocklemann, K.W. & Åkesson, B. 1989. Ophryotrocha socialis n.sp.,
a link between two groups of simultaneous hermaphrodites within
the genus (Polychaeta, Dorvilleidae). Ophelia 31(3), 145-162.
Morphology, physiology and behaviour are described. O. socialis
has the spawn and larval morphology of the hartmanii group but
retains P-type jaws of the gracilis group of species. It has
gregarious brooding in a connected tube system, facultative
external self-fertilisation and a high level of inbreeding.
OLENIN, S & CHUBAROVA, S. 1991. Marenzellaria viridis (Verril,
1873) (Polychaeta; Spionidae) : a new record from the
southeastern Baltic. Abstract in 12th Baltic marine Symposium,
Helsongor, Denmark, August 25-30,1991.
Rapid expansion has occurred into the mesohaline inner Baltic.
A single specimen was recorded near Baltijsk in 1989 and the
species was found at several locations near Baltijsk and Klaipeda
in 1990. Maximum density 5650 m-2. It had not been recorded there
in previous years of monitoring from 1981
O'Reilly, M. 1991. A guide to polychaete-infesting copepods from
British waters. Porcupine Newsletter 5(3), 63-70.
Species can be identified using Kabata, Z. & Gotto, R.V.,1991
(Parasitic and commensal copepods. Linnaean Society Synopses of
the British Fauna, new sereis no 46). About 30 species are
currently known from polychaete hosts in British waters but new
species are still bring found: descriptions given include
previously unpublished records. Myles O'Reilly, (Clyde River
Purification Board, Murray road, East Kilbride, Glasgow G75 0LA,
Scotland, U.K.) is presently collecting new records of copepods
associated with polychaetes (or other invertebrates) and he would
be delighted to receive material for identification.
Rzhavsky, A.V. 1991. Composition of the genus Bushiella
(Polychaeta, Spirorbidae) and distribution of its representatives
in the seas of the USSR; description of a new species.
Zoologicheskii Zhurnal 70(3),5-11.
Jugaria is a subgenus of Bushiella in a diagram illustrating the
structure of the family. New species Bushiella (Jugaria)
acuticostalis from Sea of Okhotsk. New USSR records for B.
evoluta (Pacific) and B. similis (Barents and White Seas).
Rzhavsky, A.V. 1991. Revision of Januinae (Polychaeta,
Spirorbidae) in the seas of the USSR. Zoologicheskii Zhurnal ,70,
(8), 37-45
N. brasiliensis is new to USSR fauna. N. nipponica is a synonym
of N. alveolata.
San Martín, G. & Viéitez, J. M. 1991. Catálago de los anélidos
poliquitos del Museo Nacional de Cienceas Naturales de Madrid.
Bull. R. Soc. Esp. Hist. Nat. (Sec. Biol.), 87(1-4) 93-131.
345 species are catalogued, most with location data. An appendix
of type specimens is given.
Sen Shoupeng & Wu Baoling. 1991. A new family of polychaeta-
Euniphysidae. Acta Oceanographica, 10, 129-140.
Separated from Eunicidae, the family includes Euniphysa aculeata,
E. oculata, E. unicusa sp nov,, Paraeuniphysa taiwanensis, P.
falciseta sp nov., P. spinea comb nov, Heterophysa tridontesa sp
nov. Some species previously included in Euniphysa are placed in
Eunice. A key to species is provided.
Wang Yonghong & Wu Baoling. 1990. Preliminary report on the
pelagic polychaetes from the South Shetland Islands, Biscoe
Islands and their vicinities. Antarctic Research 1, 20-26.
Maupasia coeca Viguier, Rhynchonerella petersii (Langernans), R.
bongrainia (Gravier) and Tomopteris planktonis Apstein are new
locality records.
Wu Baoling et al. 1991. Journal of Ocean University of Qingdao
21(3)101-102.
(in Chinese) first report of Ctenodrilus serratus from China sea
Zhao Jing & Wu Baoling. 1991. A preliminary study of the family
Paraonidae (Polychaeta) from the Huanghai Sea (Yellow Sea).
Journal of Oceanography of Hunghai and Bohai Seas 9 (2), 27-35.
(In Chinese with English summary, fully illustrated)
Aricidea quadrilobata (one specimen, atypical in its conspicuous
trilobed prostomium, short antenna etc); A. nolani (many small
specimens); Cirrophorus branchiatus (one specimen); C.
neapolitanus pacificus (new subspecies, differing in long
notopodial lobes on branchial setigers, shape of prostomium,
absence of eyes; many specimens); Tauberia gracilis (one only).
Zhao Jing & Wu Baoling. 1991. A new species of interstitial
polychaete Hesionura shandongensis sp. n. (Polychaeta,
Phyllodocidae) from Yantai, the Huanghai Sea. Acta Oceanographica
Sinica, 10(3), 447-450.
Most characteristic feature is the presence of trifid shaft head
on at least 3 compound chaetae.
Pettibone, M.H. 1991. Polynoids commensal with gorgonian and
stylasterid corals, with new genus, new combinations and new
species (Polychaeta: Polynoidae: Polynoinae). Proc Biol. Soc.
Wash.104(4), 688-713.
Descriptions and key to Gorgoniapolynoe, with modified anterior
elytra, include 5 new species.
Pettibone, M.H. 1991. Polynoid polychaetes commensal with
antipatharian corals. Proc Biol. Soc. Wash.104(4), 714-726.
3 new genera and species are described with a key to known
species (4) with this association
GRASSLE, J.F. & MACIOLEK, N.J. 1992. Deep-sea species richness:
regional and local diversity estimates form quantitative bottom
samples. The American Naturalist 139, 313-341.
Destined to be a classic paper, illustrating the high diversity
of deep (1,500-2,500m) seas from quantitative samples leading to
the suggestion that the total number of deep sea species exceeds
1 million and may exceed 10 million.
-------------------------------------------------
E T I: A Computer Approach to Taxonomy and Identification of
Organisms
P.H. Schalk
Expert-Center for Taxonomic Identification, PO Box 4766, 1009 AT
Amsterdam, Netherlands
Exact organism identifications are of the utmost importance when
environmental problems arise, or pests or diseases. Quick answers
are required, but identifying organisms is a time-consuming job
requiring expert knowledge. Though taxonomy and systematics form
the actual basis for all biological sciences, taxonomy is on the
wane and skilled taxonomists are rapidly decreasing in number,
leading to serious questions in the scientific community
concerning the preservation of this knowledge (Nature, August
1990). In developing countries especially, there is a need for
directly accessible taxonomic information and expertise. However,
institutes in these countries generally lack good library
facilities and access to scientific information and colleagues.
The Expert center for Taxonomic Identification
The Expert-center for Taxonomic Identifications (ETI) will
concentrate, preserve and promote taxonomic knowledge and provide
the possibilities to answer taxonomic, biogeographic, and
ecological questions quickly and efficiently. Present-day
computer equipment offers the possibility to modernize taxonomy
as it allows efficient handling of very large multimedial
databases. ETI is developing a database system that stores
taxonomic descriptions, drawings, photographs, video and sounds,
as well as species-related information such as distributions
maps, ecological characteristics, information on pests, diseases
etc.. The system makes fast retrieval of the data possible on a
'need-to-know' basis. Identification will be guided by an "expert
system", using both text and images as tools, thereby allowing
efficient use by experts as well as laymen. For this the system
makes use of multiple entry keys. This is a great advantage over
the traditional dichotomous keys, as the (inexperienced) user
can start with any character available on the specimen, instead
of being forced to use characters that may be difficult to
interpret or may be damaged. Moreover, the system will offer help
at every step in the identification process, and therefore
provides a maximum of taxonomic expertise to the user. In
addition teaching programmes will be developed, which can teach
inexperienced users or students the basic principles of
identification and systematics.
The ETI taxonomic databases will be stored in the main frame
computer of the University of Amsterdam, while Topic Oriented
Subsections (TOS) will be made available on CD-rom or other media
which can be run any time any place on a simple PC (Macintosh and
IBM compatibles). A TOS may cover various taxonomic groups,
areas, or applications of taxonomy. In future on-line connection
to the ETI databases will be realized.
ETI will be developed in three phases: 1] a pilot phase
during which the system will be designed and tested using two
relative small marine groups - namely pteropods and chaetognaths,
and a larger group - birds, 2] a building phase during which more
data on various groups will be entered into the system and
teaching programmes will be developed, 3] a consolidation phase
during which the database will be expanded further and expertise
made available to users. From the start the ETI organization will
set up an international network of taxonomic experts, which will
serve as the supplier of taxonomic data and can make free use of
the ETI system.
A taxonomic network
During the last decade several initiatives in various
countries were launched to use computer techniques for storing
taxonomic information and making it more easily accessible to a
broad spectrum of users. In general these initiatives were
started by specialists and concern only small specific taxonomic
groups. Many of these initiatives did not pass the initial phase
of building due to a lack of funding.
ETI is the first attempt to build a taxonomic expert center
on a larger scale. Government funding allows us to bring in
necessary expertise and equipment to expand and cover more
taxonomic groups as well as related information. It is the
intention of ETI to cooperate with other expert centers in the
field of taxonomy by promoting an exchange of know-how and
databases.
In order to build up taxonomic databases we call upon
experts all over the world. We intend to have a data input
programme available in the beginning of 1992 and invite all
taxonomists to input data of their specific groups. Inputted data
will be accompanied by a full reference to the author.
Optimization and organization of the data will be done by the ETI
staff. Contributors to ETI will receive a free copy (CD-rom) of
their taxonomic group in return for their much appreciated
services. Also, they will receive a reduction on other ETI
taxonomic programmes.
Location and organization structure
ETI is based at the Institute of Taxonomic Zoology of the
University of Amsterdam (The Netherlands). It is financially
supported by the Dutch Government (Ministry for Science and
Education, Science Policy Department), the University of
Amsterdam and UNESCO.
ETI is a non-profit organization committed to the
preservation, concentration and distribution of taxonomic
knowledge. ETI taxonomic programmes will be made available to
users for the nominal fee of the costs of production.
The staff of the ETI bureau consists of:
Dr. Peter Schalk
Biologist, director
Dr. Ken Este
Biologist, expert system specialist
Dr. Ronald Sluys
Biologist, systematist
Dr. A. Nieland
Biologist
Mr. Gideon Gijswijt
Assistant
Mss. Els Kranendonk
Secretary
Mr. Laszlo Torday
Programmer, database specialist
Do you have questions?
Please write to:
ETI
PO Box 4766
N-1009 AT Amsterdam
The Netherlands
We hope that readers of the Polychaete Research Newsletter will
be interested in helping building up an ETI programme on their
precious group!
----------------------------------------------------
Correspondence, New Members etc.
Sergey Olenin &
Sabina Chubarova
Environmental Control Laboratory Hydrometeorological Observatory
Taikos
26 Klaipeda 235800
Lithuania
Mike Bailey
Biology Laborator
National Rivers Authority Bromholme Lane
Brampton
Huntingdon
Cambs. PE18 8NE
UK
Tel: 0480 414581
fax: 0480 413381
Dr Matt Bentley
Department of Biology and Preclinical Medicine
Gatty Marine Laborator
St Andrews KY16 8BL
Scotland
Tel: 0334 76161 ext 7235
fax: 0334 78299
Dr Adrian E Friday
Department of Zoology
Downing Street
Cambridge CB2 3EJ
UK
Tel: 0223 336671(direct line)
fax: 0223 336676
Dr Martin Sheader
Department of Oceanography
The University
Highfield
Southampton SO9 5NH
UK
Tel: (0703) 595 000;
fax: (0703) 593 059
Dr Susan Smith
Fiskeriverket Kustlaboratoriet
Box 10 213
434 23 Kungbacka
Sweden.
Tel: 0300-73 720;
telefax: 0300-19 244.
Igor Eeckhaut
Université de Mons Hainaut Laboratoire de biologie marine
19 Avenue Maistriau
Bâtiment 4
7000 Mons
Belgium
Rosemary Barr
126 Longslow Rd
Market Drayton
Shropshire
UK
Dr Maura E. Conneely
Acer Environmental
Howard Court
Manor Park
Daresbury
Runcorn
Cheshire WA7 1SJ
UK.
B_rge Holte
Akvaplan-niva AS
Soendre Tollbugt. 3
N-9000 Tromsoe
Norway
Tel: (083) 85 280;
fax: (083) 80 509
Sandy J. Lipovsky
Columbia Science
PO Box 1001
Royston
B.C. VOR 2VO
Canada
Ms Gabrielle C. Moffat
Tay River Purification Board
1 South Street
Perth PH2 8NJ
UK
Tel: (0738) 27989;
fax: 0738 30997
Dr Jorge Núñez
Departmento de Zoologia Universidad de La Laguna
Tenerife
Islas Canarias
Tel: (922) 25 34 48
Geoffrey S. Turner &
Elaine Cunningham
AES Analytical & Environmental Services
Biology Building
East Howdon
Wallsend
Tyne & Wear NE28 0QD
UK
Tel: (091) 295 0833;
fax: (091) 263 0238
Dr David A. Rendall
Solway River Purification Board Rivers House, Irongray Road
Dumfries DG2 0JE
UK
Tel: (0387) 720 502;
fax: (0387) 721 154
Ms Annette Woodham
Institute of Offshore Engineering Heriot Watt University
Research Park
Riccarton
Edinburgh EH14 4AS
UK
H. Arvanitides
Aristoteleion University of Thessaloniki
School of Biology
Department of Zoology
540 06 Thessaloniki
Greece
"I am a postgraduate student working on the Polychaeta of the
North Aegean Sea".
Stefàn Aki Ragnarsson
Culterty Field Station
Newburgh
Ellon AB41 OAA
Scotland,
UK
Tel: 03586-89631
fax: 03586-89214
"I am starting postgraduate work on Lanice concheliga and would
appreciate contact with others working on this polychaete."
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