+Bioline International Official Site (site up-dated regularly)

J.L.B. Smith Institute of Ichthyology, Special Publication, No. 66, July 2001 pp.

PAVOCLINUS CAERULEOPUNCTATUS, A NEW SPECIES OF CLINID FISH (PERCIFORMES: CLINIDAE) FROM SOUTH AFRICA

G. Zsilavecz

21 Merlot, Baviaanskloof Road, Hout Bay 7800, South Africa

Code Number: fs01001

ABSTRACT

A new species of clinid fish, Pavoclinus caeruleopunctatus, is described from specimens collected and observed in 6 – 25 m, around the Cape Peninsula, on the southwest coast of South Africa. Pavoclinus caeruleopunctatus is distinguished from similar species by the first 3 dorsal-fin spines forming a moderate crest, a notch between the 3^rd and 4^th dorsal-fin spines, 1 – 3 soft dorsal rays, an anteriorly rounded head profile, and colour pattern; most characteristic in live specimens are the vivid blue spots in front and behind the eye, and also usually on the flanks.

INTRODUCTION

In May 1997, the author photographed a clinid fish that was initially identified as Pavoclinus pavo (Gilchrist & Thompson, 1908), based on the description and colour paintings in Smiths’ Sea Fishes (Smith, 1986). Observations of the true Pavoclinus pavo in September 1997 in a different environment resulted in an investigation of different seaweeds in order to find more specimens of different colours, still in the belief that all specimens were of the same species. Sightings of distinct varieties led to an attempt to classify the different specimens according to their colouration and habitat. A consistent distinction was found to be the presence of blue spots on the cheeks of some specimens, and green lines on the cheeks of others. Other differences between the two types were then noted, especially the head profile and the shape of the dorsal fin. These observations led the author to believe the blue-spotted specimens were not the same species as the green-lined fish. According to Penrith’s (1969) review of South African clinids, the “green-lined” species is Pavoclinus pavo. Communication with Dr. P.C. Heemstra of the J.L.B. Smith Institute of Ichthyology confirmed the belief that the “blue-spotted” species was probably undescribed.

This new species is assigned to the Genus Pavoclinus (as defined by Penrith, 1969) based on the similarity in body shape to other species of the genus Pavoclinus, the scaly body, the absence of supraorbital tentacles, the absence of a notch in the dorsal-fin margin before the soft rays, the presence of vomerine teeth, the fin counts, and the configuration of the intromittent organ.

METHODS

Methods of measurement are as follows: Standard Length (SL): from tip of snout (front of upper lip) to base of middle caudal fin rays. Head Length: from tip of snout to rear end of operculum. Body Depth: vertical depth at anal fin origin. Caudal Peduncle Length: from base of last anal ray to mid-base of caudal fin base. Caudal Peduncle Depth: least depth. Eye Diameter: the greatest diameter of the clear surface of the eye.

Type specimens are deposited at the J.L.B. Smith Institute of Ichthyology (RUSI), the South African Museum (SAM) in Cape Town and the U.S. National Museum of Natural History (USNM) in Washington D.C.

Pavoclinus caeruleopunctatus sp. nov.
Figs. 1-4

HOLOTYPE: RUSI 63336: male, 57.0 mm SL, Justin’s Caves, Oudekraal, Cape Peninsula (34°58.7’ S, 18°21.6’ E); depth 6 m; 19/3/2000. G. Zsilavecz, collector.

PARATYPES (All collected by G. Zsilavecz from the Cape Peninsula coast of False Bay): RUSI 63337: female, 65.5 mm SL, Castle Rock (34°14.4’ S, 18°28.8’ E); depth 8 m; 12/8/2000. RUSI 63338: male, 41.0 mm SL, Castle Rock; depth 8 m; 12/8/2000. RUSI 63339: female, 53.5 mm SL, Castle Rock; depth 8 m; 12/8/2000. RUSI 63340: female, 71.0 mm SL, Castle Rock; depth 6 m; 13/8/2000. RUSI 63341: female, 70.0 mm SL, Castle Rock; depth 10 m; 19/8/2000. RUSI 63342: female, 71.5 mm SL, Castle Rock; depth 10 m; 19/8/2000. RUSI 63343: female, 65.5 mm SL, Spaniard Rock (34°12.8’ S, 18°28.0’ E), depth 10 m; 20/8/2000. RUSI 63345: male, 57.0 mm SL, Castle Rock, depth 15 m; 26/8/2000. RUSI 63346: female, 61.5 mm SL, Castle Rock, depth 15m; 26/8/2000. SAM: 35668: male, 52.5 mm SL, Spaniard Rock, depth 10 m; 20/8/2000. SAM 35669: female, 46.5 mm SL, Justin’s Caves, Oudekraal, depth 6 m, 22/9/2000. USNM 364374, male, 38 mm SL; and USNM 364375, female, 41 mm SL, Justin’s Caves, Oudekraal, depth 6 m, 22/9/2000.

DIAGNOSIS: Dorsal fin with 29 – 33 spines and 1 – 3 soft-rays, the first 3 dorsal spines elevated, about twice length of 4^th spine, the membrane between 3^rd and 4^th spines slightly notched, reaching about two-thirds up length of 4^th spine and hyaline. Live specimens display bright blue spots on the head, both in front and behind the eyes, often on the flanks as well. Body moderately compressed, anterior head profile relatively blunt, the snout short and rounded, caudal peduncle length 35 – 45% head length.

DESCRIPTION: (Data from 15 specimens, 38.0 mm to 71.5 mm SL; data from the holotype are given in parentheses.) D XXIX-XXXIII,1-3 (XXXIII,2), usually XXXI,2; A II,19-21 (II,21), usually II,20; P 12; V I,3. Body moderately compressed, with small, barely overlapping, embedded cycloid scales extending to base of dorsal fin, but not onto caudal, anal or pectoral fin bases. Body depth 3.7 – 4.7 in SL; caudal peduncle length 35 – 45% head length; peduncle depth 20 – 29% head length; head blunt, the dorsal and ventral profiles almost straight, head length 3.8 – 4.3 in SL, eye diameter distinctly longer than snout, 3.3 – 4.3 in head length; no supraorbital tentacle, tentacle on anterior nostril simple, flap-like; mouth slightly oblique, lips fleshy, but no prominent skin flap on lower jaw at symphysis; a small chevron-shaped row of teeth on vomer. Gill-rakers in outer series on first arch (2 – 3) + (5 – 6). Anterior edge of the cleithrum with a pronounced upturned hook (Fig. 2). Dorsal-fin origin over preopercle; fin margin with a distinct crest

Figure 1. Paviclinus caeruleopunctatus, holotype, male 57 mm SL, RUSI 63336.

formed by the elevated first 3 spines, 2^nd spine longest; membrane between 3^rd and 4^th dorsal spines hyaline, attached to about proximal two-thirds of 4^th spine; distance between 3^rd and 4^th spines about twice distance between 4^th and 5^th spines; dorsal spines 4 – 6 and sometimes 7^th shorter than subsequent spines, which gradually lengthen posteriorly; dorsal-fin rays about equal in length to last spine. The membrane between the dorsal rays is always hyaline, often the last two rays, if present, have their ends curved towards each other to form an oval “window”; the last ray is joined completely by membrane to caudal peduncle. Anal-fin spines weak. Pelvic fin with 1 rudimentary spine and 3 rays, the 3^rd ray minute and barely free from membrane, distal third of 1^st and 2^nd rays free from membrane. Pectoral fin rounded, the middle ray longest. Caudal fin rounded, with 13 segmented rays.

Intromittent organ (Fig. 3) with a large conical tip emerging between a pair of curved lips.

Head pore system as shown (Fig. 4), lateral line with 26 – 29 simple pores (data from 3 specimens) opening above and below the line until the post-pectoral curve, thence posteriorly as short, separate horizontal tubes with an opening on either end.

REPRODUCTION: A gravid female (71 mm SL) contained at least 15 fetuses, 4.5 to 16.5 mm total length. At this stage they are white and very slender, with large eyes. All fetuses were curled into a circle.

COLOURATION: Ground colour variable, buff, white, reddish, green or brown, with a pattern of 6 vertical bars along the body not extending onto the dorsal or ventral fins, in either yellow, pink, red, green, brown or dark blue. On the body the colour of the area between the bars is generally paler than the colour of the bars. There are 6 bars on the dorsal fin just extending onto the body, and 6 or 7 bars on the anal fin not extending onto the body; the colour of these bars matches that of the bars along the flanks. The fin membranes between the bars on both dorsal and anal fins is hyaline. The membrane between the first 3 dorsal-fin spines is always in the main body colour, while the membrane of the notch between 3^rd and 4^th dorsal spine is always hyaline. The membranes of the pectoral and caudal fins are hyaline. The tips of the pectoral fin rays are a golden yellow.

On each side of the head, a horizontal “Y” shaped orange or light red coloured area extends from the upper jaw through the eye, with the upper branch terminating at the top of the head, the lower branch terminating on the opercle. This area is speckled with contrasting bright blue spots. Blue spots are also usually present within the vertical bars on the body as well as within the lower part of the bars extending onto the body from the dorsal fin. A dark line down from the eye is always present. The pupils of the eyes are black, with a bright red iris.

HABITAT AND DISTRIBUTION: Pavoclinus caeruleopunctatus have been observed at Robben Island (Table Bay), around the Cape Peninsula to the Rooi Els, Gans Baai, Knysna Heads and possibly Tsitsikamma (pers. comm. A. Smook). The species occurs in a variety of seaweeds, hydroids and soft corals, but only in waters beyond the intertidal area; the shallowest specimen was found on a reef 15 m from shore at a depth of 6m;

Figure 2.           Rear part of left gill cavity showing pronounced hook on the anterior edge of cleithrum of the holotype.
Figure 3.           Pavoclinus caeruleopunctatus, ventral and lateral view of the intromittent organ of the holotype.
Figure 4.           Pavoclinus caeruleopunctatus, pores and canals of the lateralis system of the holotype.

other specimens were seen on reefs at depths of up to 25 m and to at least 3 nautical miles offshore.

DISCUSSION:

Pavoclinus caeruleopunctatus differs from P. pavo, which also has a dorsal-fin crest and a similar number of fin rays, by having a blunter head profile, a more pronounced dorsal crest with a notch between the 3^rd and 4^th spines, which is not present in P. pavo. It can be distinguished from P. graminis, P. laurentii, P. litorafontis and P. mentalis by the lower dorsal and anal-fin ray counts (1 – 3 and 19 – 21 respectively), versus P. graminis (4 – 6 and 21 – 24), P. laurentii (4 – 5 and 20 – 22), P. litorafontis (7 – 8 and 20 – 23) and P. mentalis (6 – 8 and 27 – 32) respectively (Smith, 1986). It can be distinguished from Pavoclinus myae by a shorter caudal penduncle: peduncle length 35 – 45% HL for specimens 38.0 – 71.5 mm SL, versus P. myae peduncle length 56 – 61% HL, for specimens 29.9 – 44.0 mm SL (Christensen, 1978).

The initial confusion by the author of P. caeruleopunctatus with P. pavo came from both species inhabiting seemingly similar habitats. Observations revealed that this is actually rarely the case, with only an overlap in certain habitats, mainly Caulerpa sp. beds. Whereas P. pavo are most abundant inshore at depths of 0 to 5 m (Prochazka, 1997) and have been observed rarely by the author in depths beyond 10 meters, P. caeruleopunctatus have not been observed close inshore, or in very shallow waters. Although it has been found in waters 6 m deep, P. caeruleopunctatus is seen on reefs offshore, where its range extends to a depth of at least 25 meters.

The colouration of Pavoclinus caeruleopunctatus usually reflected the environment in which they were found, for example: yellow fish in yellow hydroids such as Aglaophenia pluma and Sertularella arbuscula, dark blue individuals in blue or grey hydroids such as Lytocarpus filamentosus, intense pink or red fish in Plocamium corallorhize, and green individuals in green algae (Caulerpa sp.). Specimens with red or maroon vertical bars were found in Leptogorgia palma, and the fish were observed to “weave” themselves into the branches on days with a strong surge. Pavoclinus caeruleopunctatus were observed during the day and night.

Examination of the food regurgitated food by P. caeruleopunctatus revealed amphipods, including a few Caprella equilibria.

ETYMOLOGY: caeruleopunctatus: caeruleo - blue, punctatus - spotted, referring to the vivid blue spots on the cheeks and along the body.

ACKNOWLEDGMENTS

I would like to thank the following people for their encouragement, assistance and support: Dr. Phil and Elaine Heemstra, Wouter Holleman, Joan Wright and James Stapley, all from the JLB Smith Institute of Ichthyology, Dr. Kim Prochazka of the Department of Zoology, University of Cape Town, my friends and dive buddies Angie Smook and Jean-Pierre Arabonis, and my parents.

REFERENCES