Special Publication J.L.B. Smith Institute of Ichthyology ISSN: 0075-2088 Num. 59, 1997, pp. 1-8

A NEW SPECIES OF THE FLATFISH GENUS CHASCANOPSETTA (PLEURONECTIFORMES: BOTHIDAE), FROM THE COASTS OF KENYA AND SOMALIA WITH COMMENTS ON C. LUGUBRIS
by
Dannie A. Hensley^1 and Malcolm J. Smale^2

^1 Department of Marine Sciences, University of Puerto Rico, Mayaguez, Puerto Rico, 00681, U.S.A.
^2 Port Elizabeth Museum, P.O. box 13147, Humewood, 6013, South Africa

Code Number: FS97002
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ABSTRACT

Six species of the genus Chascanopsetta are currently recognized. Recent work on otolith morphology from specimens identified as C. lugubris raised the possibility that three forms of C. lugubris are found in the western Indian Ocean. Re-examination of the voucher specimens showed that one of these forms is a new species, C. kenyaensis, from Kenya and Somalia. The other two forms may show differences in otolith morphology due to ontogeny. The new species most closely resembles C. prorigera from the Hawaiian Archipelago, Emperor Seamounts, and the western North Atlantic. These two species differ in lateral-line scale counts, body depth, upper-jaw length, and coloration. Many comparative specimens of C. lugubris were examined. It was found that this species' distribution rounds the Cape of Good Hope from the southwestern Indian Ocean into the southeastern Atlantic. Specimens from this southern African region show higher dorsal- and anal-fin ray counts than those from more northern areas in the Atlantic, western Pacific, and Indian oceans. There is some indication that what some authors refer to as the Indo-West Pacific subspecies C. lugubris lugubris rounds the Cape of Good Hope and also occurs in pans of the eastern Atlantic. A more thorough comparison of C. lugubris from different regions is needed.

INTRODUCTION

The bothid genus Chascanopsetta Alcock, 1894 was revised by Amaoka and Yamamoto ( 19 84). Amaoka and Parin ( 19 90) described a new species (C. megagnatha) from seamounts in the Sala-y-Gomez Ridge in the eastern Pacific. Hensley (1986) presented a description of C. lugubris Alcock, 1894 from southern Africa.

Based on otolith morphology, Smale et al. (1995) recognized three forms of Chascanopsetta from southern and eastern Africa. We re-examined voucher specimens of these fishes in the collection of the J.L.B. Smith Institute of Ichthyology and found that one of the forms is a new species. In the present paper we describe this new species of Chascanopsetta based on five specimens from the coasts of Kenya and southern Somalia, and present a key to the seven known species of the genus.

Smale et al. (1995) emphasized how otolith studies can contribute important information to systematists and the importance for voucher specimens of fishes to be deposited in reference collections. The present study is an excellent example of the points made by these workers. Without examination of otoliths and preservation of voucher specimens, this undescribed species would have gone unnoticed.

METHODS

Methods for making counts and measurements followed those of Hubbs and Laglet (1949) with the following changes: because all dorsal- and anal-fin rays are unbranched, all ray elements were counted as individual rays; lengths of pelvic-fin bases were measured from the base of the first ray to the base of the last ray. Unless otherwise stated, measurements on whole specimens refer to those made on the ocular side. These measurements were made with dial callipers or an ocular micrometer to the nearest 0.1 mm. Gill-rakers were counted on the left side of the first gill arch. Methods and terminology for otolith preparation and description follow Smale et al. (1995).

Institutional abbreviations are as listed by Leviton et al. (1985). The biogeographic terms "Indo-Pacific" and "Indo-West Pacific" are as defined by Springer (1982). Otoliths described in this paper were taken from a subset of specimens collected by P.C. Heemstra in Kenya. They were not removed from the type specimens.

Chascanopsetta kenyaensis, sp. nov.

Figure 1. Chascanopsetta kenyaensis, holotype, RUSI 44244, 225 mm SL; lower, head of same specimen.

Holotype: RUSI 44244, 225 mm SL, male, off Kenya, 04 degrees 38'S, 39 degrees 46'E, depth less than or equal to 350 m, 9 Dec. 1980, R/V FRIDTJOF NANSEN sta 852; P.C. Heemstra, collector.

Paratypes: RUSI 13780, 250 mm SL, male, collected with holotype; RUSI 13743, 2 specimens, 223-294mm SL, 1 male and 1 female, off Kenya, 03 degrees 26'S, 40 degrees 23'E, depth 484 m, 11 Dec. 1980. R/V FRIDTJOF NANSEN sta 862; ZMB 17684, 199 mm SL, male, off southern Somalia, depth 638 or 977 m, VALDIVIA sta 253 or 254.

Otoliths: PEM 5038, 5036, 5037, 3 from right side, 3 from left side, greatest diameter 3.0-3.85 mm, removed from specimens 276-303 mmTL collected with RUSI paratypes.

DIAGNOSIS:

A species of Chascanopsetta with the following combination of characters: body depth 3.6-4.7 in SL (24-28% SL); upper-jaw length 1.4-1.6 in head length (13.1-15.8% SL), maxilla extending beyond rear margins of eyes; lower-jaw length 1.1 - 1.2 in head length ( 18-20% SL), ventral surface of mandibles with thin bony lamella near middle of length; anal-fin rays 86-90; lateral-line scales 171-181; lower-limb gill-rakers 10-13; vertebrae 16 + 4041 = 56-57; no large, conspicuous dark blotches on lateral line.

DESCRIPTION:

Data for the holotype are presented, followed by those for the paratypes in parentheses. Morphometrics expressed as percent SL: head length 23 (21-23); body depth 26 (24-28); snout length 6.2 (6.3-6.8); upper jaw length ocular side 16 (13-14), blind side 16 (13-14); mandible length ocular side 20 (18-19), blind side 21 (19-20); lower-eye length 6.4 (4.9-5.5), upper-eye length 6.2 (4.7-5.3); interorbital width 1.8 (1.6-2.0); pectoral-fin length ocular side 11.1 (10.9-11.1), blind side 7.1 (5.8-6.4); length of third pelvic-fin ray ocular side 4.5 (4.4-5.2), blind side 4.5 (3.8-5.8); length of pelvic-fin base ocular side 3.7 (3.2-3.8), blind side 2.1 (1.9-2.4); length of first dorsal-fin ray 6.6 (6.4-7.8), second dorsal-fin ray 7.9 (7.1-7.8), third dorsal-fin ray 7.1 (6.6-6.9), fourth dorsal-fin ray 6.3 (5.6-6.8), fifth dorsal-fin ray 5.9 (6.1-6.9), sixth dorsal-fin ray 5.8 (5.0-6.2), ray near middle of fin 9.0 (8.8-9.0);length of first anal-fin ray 4.1 (3.6-4.1), ray near middle of fin 8.3 (8.1-9.2); depth of caudal peduncle 5.1 (4.6-5.1), length of caudal peduncle 2.8 (3.4-3.9).

Morphometrics expressed as ratios of larger measurements: Head length 4.3 (4.4-5.2), body depth 3.8 (3.6-4.7), both in SL. Measurements in head length: Snout length 3.7 (3.2-3.6); upper-jaw length ocular side 1.4 (1.5-1.6), blind side 1.4 (1.5-1.6); lower-jaw length ocular side 1.1 (1.1-1.2), blind side 1.1 (1.1-1.2); lower-eye length 3.6 (4.1-4.4), upper-eye length 3.7 (4.1-4.7); interorbital width 12.8 (10.7-13.6); pectoral-fin length ocular side 2.0 (2.0-2.1), blind side 3.2 (3.6-3.7); length of third pelvic-fin ray ocular side 5.1 (4.3-5.0), blind side 5.1 (3.9-5.7); length of pelvic-fin base ocular side 6.2 (5.8-6.6), blind side 10.9 (8.9-11.4); length of first dorsal-fin ray 3.5 (2.8-3.5), second dorsal-fin ray 2.9 (2.8-3.2), third dorsal-fin ray 3.2 (3.2-3.3), fourth dorsal-fin ray 3.6 (3.3-3.8), fifth dorsal-fin ray 3.9 (3.3-3.6), sixth dorsal-fin ray 3.9 (3.54.6), ray near middle of fin 2.5 (2.3-2.6); length of first anal-fin ray 5.5 (5.6-6.0), ray near middle of fin 2.7 (2.3-2.7); depth of caudal peduncle 4.5 (4.2-4.8), length of caudal peduncle 8.0 (5.6-6.7).

Dorsal-fin rays 122 (120-123); anal-fin rays 88 (86-90); pectoral-fin rays ocular side 13 (15-17), blind side 14 (14-16); pelvic-fin rays ocular side 6 (6), blind side 6 (6); caudal-fin rays 17 (16-17), innermost 12-13 branched; lateral-line scales 174 (171-181); gill-rakers ocular side = 0 + 10 (0-2 + 12-13); vertebrae 16 + 40 (40-41) = (56-57).

Profile of head concave anterior to interorbital region, becoming convex above upper eye. Interorbital region concave, naked. Anterior margins of both eyes on same vertical line. Maxilla extending a short distance posterior to vertical through posterior margins of eyes. Approximately 6-11% of lower jaw length projecting anterior to symphysis of upper jaw; ventral surface of each mandible with a long thin bony lamella (Fig 2A). Nostrils on ocular side at same level as upper margin of lower eye, anterior nostril tubular, posterior nostril slit-like; anterior nostril on blind side tubular, below first dorsal-fin ray; posterior nostril slit-like. Tip of isthmus at about same level as posterior tip of retroarticular. Teeth of both jaws uniserial, depressible, caniniform, curved inward, about equally developed on ocular and blind sides, becoming somewhat larger anteriorly; teeth of lower jaw larger and more widely spaced than upper-jaw teeth, tips of anterior lower-jaw teeth of ocular and blind sides touch or cross when depressed. Ocular and blind sides of first gill arch with small gill-rakers (Fig. 3A).

Figure 2. Lower-jaw configuration of western Indian Ocean species of Chascanopsetta. A: C. kenyaensis, dilated bony lamella shown in black; B: C lugubris, C: C. prognathus; D: C. crumenalis; mandibular membrane of B,C, and D stippled.

Figure 3. Ocular side of first gill arch to show (A) small gill-rakers of Chascanopsetta kenyaensis, 250 mm SL, RUSI 13780; and (B) minute teeth on gill arch of C. lugubris, 256 mm SL, RUSI 30328.

Colour in alcohol: Ground colour on ocular side tan, with many scattered small dark spots. Abdominal area dark blue or black with several tan stripes slanting anteroventrally formed from narrow hypaxial myotomes. Median fins and ocular-side pelvic fin dusky. Pectoral fin of ocular side light brown. Blind side tan to cream coloured, with darkened abdominal region similar to that on ocular side.

OTOLITH MORPHOLOGY

Figure 4. Otoliths (sagittae) of A. Chascanopsetta kenyaensis A1. PEM 5037 - L. 3.8 mm OD, 303 mm TL. A2. PEM 5037 - R. 3.85 nun OD. B. Chascanopsetta kenyaensis B1. PEM 5036 - L. 3.25 mm OD, 280 mm TL. B2. PEM 5036 - R. 3.2 mm OD. C. Chascanopsetta lugubris. C1. PEM 16128 (voucher specimen RUSI 48194) - L. 2.3 mm OD, 365 mm TL, 318 mm SL. C2. PEM 16128 - R. 2.6 mm OD.

DISTRIBUTION:

Known only from the coasts of Kenya and southern Somalia.

HABITAT:

Collected from depths of 350, 484, 638, and 977 m. At station 253 of the VALDIVIA expedition, this species (identified as C lugubris) was collected on "pteropod mud and blue clay" bottom (Brauer, 1906).

REMARKS:

Chascanopsetta kenyaensis most closely resembles C. prorigera Gilbert, 1905, known only from the Hawaiian Archipelago, Emperor Seamounts, and western North Atlantic (Gutherz, 1967; Amaoka and Yamamoto, 1984). The two species are separable by lateral-line scale counts (171-181 vs. 135-154 in C prorigera), body depth (Fig. 5A), upper-jaw length (Fig. 5B), length of upper jaw (extending a short distance behind lower-eye vs. reaching vertical at posterior lower-eye margin), and coloration (no large, conspicuous dark blotches on lateral line vs. three such blotches on lateral line).

Figure 5. Plots of (A) body depth and (B) upper-jaw length against standard length for two species of Chascanopsetta.

Chascanopsetta lugubris is known from the western Pacific, Indian Ocean, and both sides of the Atlantic (Gutherz, 1967; Amaoka and Yamamoto, 1984). Some authors have considered the Atlantic populations as a separate subspecies, i.e. C lugubris danae Bruun, 1937 (Poll, 1959; Amaoka and Yamamoto, 1984). Some other workers did not do this or expressed doubt that there are detectable differences between the Atlantic and Indo-West Pacific populations (Deubler and Rathjen, 1958; Gutherz, 1967, 1981; Nielsen 1961a,b, 1984; Smith 1961; Blache et al., 1970; Randall and Vergam, 1978; Hensley, 1986; Lloris, 1986; Aidebert et al., 1990). It has been implied or stated that the Cape region of South Africa is acting as a partial barrier to gene flow between the two subspecies of Chascanopsetta lugubris in the Atlantic and Indo-West Pacific (Bruun, 1937; Nielsen, 1961a; Amaoka and Yamamoto, 1984). This idea may have been based on the southernmost distribution records of post-metamorphic specimens from southern Africa, i.e. Kwazulu-Natal (29 degrees 55'S, 31 degrees 20'E) on the east coast (reported as C. galathea Nielsen, 1961 b, a junior synonym of C. lugubris) and northern Namibia (18 degrees 01'S, 11 degrees 26'E) on the west coast (Lloris, 1986). The scenario apparently was that some larvae occasionally do go around the Cape of Good Hope into the eastern Atlantic. Our findings show that C. lugubris are found as post-metamorphic, benthic individuals from the Indian Ocean around the Cape of Good Hope into the eastern Atlantic. Whether or not they breed in the southern Cape localities is unknown. All of our specimens from these areas were juveniles (130-139 mm SL).

Penrith (1976) in a study of distributions of shallow-water marine fishes (those found from intertidal areas to depths of 50 m) in southern Africa, recognized four distribution patterns in the area: 1) circumtropical species; 2) western Indian Ocean and east coast endemics, which enter the cold west coast or reach into the tropical Atlantic; 3) tropical Atlantic species which occur in the Agulhas Province (area between the Kei or Bashee rivers and Cape Agulhas); and 4) Indo-Pacific or Indo-West Pacific fishes that round the Cape. Although C. lugubris is a deep-water species found at depths of 120-910 m, its distribution would fit Penrith's fourth category, although this species' range also extends to the western Atlantic. Current work on slope fishes in southern Africa has also shown four distribution patterns: 1) Indo-Pacific or Indo-West Pacific species that round the Cape; 2) circumglobal species; 3) Atlantic species rounding the Cape into the southwestern Indian Ocean; and 4) Southern Ocean fishes occurring in southern Africa (M.E. Anderson, pers. comm.). The distribution of C. lugubris apparently fits into the first category.

An important character used by Amaoka and Yamamoto (1984) for distinguishing the two subspecies is the ratio of upper-jaw length into head length (1.29-1.69 for the Indo-Pacific subspecies and 1.12-1.27 for the Atlantic subspecies). Their Fig. 6 is a scatter plot of this ratio vs. SL (note that their legend contains a typographical error stating that it is plot of lower-jaw length into head length vs. SL). Cadenat (1937), Bruun (1937), Poll (1959), Nielsen (1961a) and Lloris (1986) give this ratio (1.2-1.3 for upper jaw in head length) in their accounts of C. lugubris from Guinea-Bissau to northern Namibia (Areas 1 and 2 in Fig. 6); these data indicate that their specimens represent intermediates between the two subspecies or they are specimens of C. l. lugubris, the Indo-West Pacific form. We examined two specimens from the west coast of southern Africa; both were easily identified as specimens of the Indo-West pacific C. lugubris lugubris using the key and scatter plots published by Amaoka and Yamamoto (1984). Most of the specimens examined by these workers were from the western Atlantic and near Ascension Island; only four of their specimens were collected in the eastern Atlantic from Gabon. Obviously a more thorough comparison using more material from many more arcas is needed before variation in C. lugubris can be adequately assessed. This is especially true in regard to comparing material from the eastern and western Atlantic.

Figure 6. Known distribution of Chascanopsetta lugubris in the western Indian Ocean and eastern Atlantic with meristic data for different areas.

-------------------------------------------------------------------------
Areas    D.           A.                    Sources
-------------------------------------------------------------------------
 1    115-120       80-87    Bruun (]937), Cadanet (1937), Poll (1959)
 2    115-122       77-85    Poll (1959), Nielsen (1961), Lloris (1986,),   
                                specimen examined from northern Namibia
 3      128          89      Specimen examined from Western Cape Prov.
 4  *(115) 122-126  88-89    Specimens examined from Eastern Cape Prov.
 5    122-129       84-90    Specimens examined from KwaZulu-Natal 
 6    121-131       83-89    Specimens examined from Mozambique
 7    114-122       81-85    Norman (1927)
-------------------------------------------------------------------------

* Only two specimens available for study from the Eastern Cape Province; one of these is the only specimen showing dorsal-fin ray counts within the ranges of those from more northern latitudes,

Specimens from the Eastern Cape Province, Kwazulu-Natal, and Mozambique (areas 4-6, Fig. 6) al so showed high menstic values (D 121 - 131, A 83 -90), with the exceptlon of one specimen from the Eastern Cape Province with a dorsal-fin ray count (115) within the range found for the specimens from the northern latitudes. Other specimens from the western Indian Ocean have been collected near the southern tip of Sri Lanka. These show ranges in fin-ray counts very similar to those from eastern Atlantic areas 1 and 2. With the exception of the specimen from the Eastern Cape Province, there appears to be little overlap in these characters with specimens from both Guinea Bissau to northern Namibia and the northern Indian Ocean (D114-122, A 77-87) with those from the southwestern Indian Ocean and the western side of the Cape of Good Hope (D 121-131, A 83-90). We are uncertain if this is simple clinal variation because there are large areas in the eastern Atlantic (northern Namibia to just north of the Cape of Good Hope) and the eastern Indian Ocean (India to Tanzania) where this species has not been collected.

KEY TO SPECIES OF CHASCANOPSETTA

(modified from Amaoka and Yamamoto, 1984)

1a. Gill-rakers on lower limb of left side of first gill arch 8-13;         
     upper-jaw length 1.4-1.8 in head length, reaching below or a short     
     distance beyond rear margin of lower eye; bony lamella on ventral      
     surface of both sides of lower jaw  .  .  .  .  .  .  .  .  .  .  .  2

1b. Lower-limb gill-rakers 0-5; upper-jaw length 0.9-1.5 in head length     
     (1.2-1.7 in specimens less than 14 cm SL), reaching far beyond lower   
     eye; no bony lamella on lower jaws  .  .  .  .  .  .  .  .  .  .  .  4

    
2a. Anal-fin rays 85-90; caudal vertebrae 40-41  .  .  .  .  .  .  .  .  3

2b. Anal-fin rays 93-98; caudal vertebrae 42-44  Chascanopsetta micrognatha
                                (Kyushu-Palau Ridge and Philippine Islands)


3a. Lateral-line scales 135-154; body depth 2.5-3.0 times in SL (Fig. 5A);  
     upper-jaw length 1.6-1.8 times in head length (Fig. 5B); maxilla       
     extending to below posterior margin of lower eye; three conspicuous    
     dark blotches on straight section of lateral line, one at anterior     
     end, middle, and near posterior end .  .  .   Chascanopsetta prorigera
      (Hawaiian Archipelago, Emperor Seamounts, and western North Atlantic)

3b. Lateral-line scales 171-181; body depth 3.6-4.7 in SL (Fig. 5A);        
     upper-jaw length 1.4-1.6 in head (Fig. 5B); maxilla extending a short  
     distance posterior to lower eye; no conspicuous dark blotches on       
     lateral line    .  .  .  .  .  .  .  .  .    Chascanopsetta kenyaensis
                                     (coasts of Kenya and southern Somalia)


4a. Lower jaw projecting slightly in front of upper jaw, its length 0.9-1.4 
     in head length; upper-jaw length 1.1 - 1.7 in head.  .  .  .  .  .  .  
     .  .  .  .  .  .  .  .  .  .  .  .  .  .  .    Chascanopsetta lugubris
                       (Indo-West Pacific and eastern and western Atlantic) 

4b. Lower jaw projecting well beyond upper jaw, its length 0.6-0.8 in head;
     upper-jaw length 0.9-1.0 in head  .  .  .  .  .  .  .  .  .  .  .  . 5 
    

5a. Dorsal-fin rays 111-118; anal-fin rays 71-81; caudal vertebrae 36-39
    .  .  .  .  .  .  .  .  .  .  .  .  .  .  .   Chascanopsetta megagnatha 
                         (seamounts of Sala-y-Gomez Ridge, eastern Pacific)

5b  Dorsal-fin rays 119-133; anal-fin rays 84-93; caudal vertebrae 39-44    
    .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .   6


6a. Lateral-line scales 185-196; lower-jaw length ca. 0.8 in head length,   
     less than 18% of lower-jaw length projecting anterior to symphysis of
     upper jaw; caudal vertebrae 42-44  .  .  .  . Chascanopsetta prognatha
                  (Sagami Bay, Japan, Okinawa Trough, Maldive Islands area) 

6b. Lateral-line scales 190-241; lower-jaw length 0.6-0.8 in head length,
     ca. 28% of lower-jaw length projecting anterior to symphysis of upper  
     jaw; caudal vertebrae 39-41  .  .  .  .  .   Chascanopsetta crumenalis
                                                     (Hawaiian Archipelago)

COMPARATIVE MATERIAL EXAMINED -

Chascanopsetta prorigera: Hawaiian Archipelago; BPBM 24958, 3 specimens, 265-3 17 mm SL, Leeward Islands, SE Hancock Seamount, 308 m, R/V Townsend Cromwell, Cr. 79-02, sta 37, 6 May 1979.

C. lugubris: ATLANTIC OCEAN: Namibia; SAM 32529, 285 mm, 20 degrees 30' - 21 degrees 00' S, 12 degrees 00'E, 350 m, 1992. South Africa, Western Cape province; RUSI 43636, 139 mm, 33 degrees 51'S, 17 degrees 49' E, 230 m, R/V Africana, Cr. 118, sta A 15768, 1 October 1994. INDIAN OCEAN: South Africa, Eastern Cape province; RUSI 48733, 2, 134 - 145 mm, 25 degrees 11' E, 34 degrees 45'S, 910 m, R/V Africana, Cr. 122, sta A 16440,7 January 1994. RUSI 35521, 130 mm, 34 degrees 13.8'S, 26 degrees 38.2'E, 250 m, R/V Africana sta A10138-082, 6 February 1990. RUSI 503 17, 134 mm, 34 degrees 29' S, 25 degrees 36.6'E, 70m, R/V Africana, Cr. A7166, sta 063, 22 May 1988. Kwazulu-Natal; BMNH 1922.3.27:1-2 (paratypes of C. maculata), 2, 128211 mm, 29 degrees 45'30"S, 31 degrees 34'45"E, and 29 degrees 48'55"S, 31 degrees 22'30"E, 383-495 m, S.S. Pickle, sta 140 and 141, 9 July 1920. BMNH 1922.3.27:3 (paratype of C. gilchristi), 177 mm, 25 degrees 41'20"S, 33 degrees 23'45"E, 605 m, S.S. Pickle, sta 293, 8 February 1921. RUSI 14585, 182 mm, DURBAN, October 1967. RUSI 30328, 256 mm, 29 degrees 47'S, 31 degrees 23'E, 350 m, R/V Africana, sta A4709-T-03, 26 August 1986. RUSI 30337, 177 mm, 30 degrees 48'S, 31 degrees 13'E, 467 m, R/V Africana, sta A4711-047, 26 August 1986. SAM 16747, 2, 151-156 mm, Kwazulu-Natal coast, shallow. SAM 27200, 256 mm, 27 degrees 31.0'S, 32 degrees 45.6'E, 280-454 m, R/V Meiring Naude, sta SM 15, 25 May 1975. ZMK P 853091 (paratype of C. galatheae), 235 mm, 29 degrees 55'S, 31 degrees 20'E, 425 m, R/V Galathea sta 196. ZMK P 853103 (paratype of C. galatheae), 278 mm, 25 degrees20'S, 35 degrees 17'E, 575-595 m, R/V Galatheae sta 202. ZMK P 853104 (holotype of C. galatheae), 141 mm, same locality and depth as ZMK P 853103. Mozambique; RUSI 34089, 3, 145-194 mm, south of Maputo, December 1987. RUSI 48172, 4, 137-268 mm, 17 degrees 33'S, 38 degrees 27'E, 433 m, R/V Algoa sta C823-014, 15 June 1994. RUSI 48194, 2, 262-304 mm, 21 degrees 22'S, 35 degrees 40'E, 481 m, R/V Algoa, sta C816-014, 13 June 1994. SAM 33677, 262 mm, same collection data as RUSI 48194. SAM 33678, 2, 143-252 mm, same collection data as RUSI 41872. SAM 33679, 2, 268-331 mm, 18 degrees 14'S, 37 degrees 31'E, 472 m, R/V Algoa sta C828-014, 17 June 1994. SAM 33680, 275 mm, 21 degrees 34'S, 35 degrees 39'E, 465 m, R/V Algoa sta. C837-014, 19 June 1994. SAM 33709, 3, 243-260 mm, 16 degrees 20'S, 40 degrees 8'E, 500 m, R/V Algoa sta C826-014, 16 June 1994.

ACKNOWLEDGEMENTS

We are grateful to P.C. Heemstra (RUSI) for collecting the specimens of the new species and arranging for the senior author to visit museums in South Africa, R. Stobbs (RUIS) for taking radiographs of specimens, J.E. Randall and A.Y. Suzumoto (BPBM) for loan of comparative material, H.-J. Paepke for the loan of the ZMB specimen, M.E. Anderson for discussions on distributions of slope fishes in southern Africa, Elaine Heemstra for the drawings, Gilljan Watson for the excellent otolith micrographs taken at the Rhodes Electron Microscope Unit, Rob Cross, S.C. Pinchuck and N.J. Cannon for their help, and the South African Foundation for Research Development, Rhodes University, and the United States Fulbright Scholarship Programme for supporting the senior author's visit to South Africa.

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