Two new damselfishes of the genus Pomacentrus from the south-west Pacific

Transcription

1 aqua, Journal of Ichthyology and Aquatic Biology Two new damselfishes of the genus Pomacentrus from the south-west Pacific John E. Randall Bishop Museum, 1525 Bernice St., Honolulu, HI , USA Accepted: Keywords Taxonomy, Pomacentridae, Pomacentrus, new species, south-west Pacific Abstract Pomacentrus callainus, formerly identified as a colour variety of the western Pacific P. lepidogenys, is described from specimens from Tonga and Fiji. It is distinct from P. lepidogenys in its overall blue-green colour with a wedge-shaped black spot at the upper base of the pectoral fin, higher gill raker counts (22-25, compared to for P. lepidogenys), deeper body ( % SL compared to % SL, for P. lepidogenys), longer dorsal spines (longest spine % SL, compared to % SL in P. lepidogenys), and probable larger size. Pomacentrus spilotoceps is described as new from four specimens from Tonga and underwater photographs from Fiji. Its closest relative appears to be P. chrysurus, known from the western Pacific to the Maldive Islands. P. spilotoceps differs in having in orange or yellow spots on the operculum and before and above the base of the pectoral fins and gill rakers, compared with for P. chrysurus). Zusammenfassung Pomacentrus callainus, früher als Farbvariante von P. lepidogenys aus dem westlichen Pazifik bezeichnet, wird anhand von Exemplaren aus Tonga und Fidschi beschrieben. Diese Art unterscheidet sich von P. lepidogenys durch ihre gesamt blaugrüne Farbe, einen keilförmigen schwarzen Punkt an der oberen Basis der Brustflosse, eine größere Anzahl von Kiemenreusen (22 25, im Vergleich zu in P. lepidogenys), einen höheren Körper ( % SL im Vergleich zu % SL in P. lepidogenys), längere Rückenflossendornen (der längste % SL, im Vergleich zu % in P. lepidogenys), sowie ein vergleichbar größeres Körperausmaß. Pomacentrus spilotoceps wird anhand von vier Exemplaren aus Tonga sowie von Unterwasserfotografien aus Fidschi, als neu beschrieben. Der naheste Verwandte dieser Art scheint P. chrysurus sein, die im westlichen Pazifik bis zu den Maldiven hin vorkommt. P. spilotoceps unterscheidet sich von P. chrysurus durch die Anwesenheit von orangefarbigen oder gelben Punkten auf dem Kiemendeckel, sowie vor und über der Basis der Brustflossen und durch Kiemenreusen (im Vergleich zu in P.chrysurus). Résumé Pomacentrus callainus, jadis identifié comme variété de couleur de P. lepidogenys du Pacifique ouest, est décrit à partir de spécimens de Tonga et de Fidji. Il se distingue de P. lepidogenys par sa couleur générale bleu-vert avec une tache noire cunéiforme à la base supérieure de la pectorale, un nombre plus élevé de branchiospines (22-25, contre pour P. lepidogenys), un corps plus haut (47,5-51% de la LS contre 43,5-47% de la LS pour P. lepidogenys), des épines dorsales plus longues (la plus longue 14,7-17,1% de la LS contre 12,7-14% de la LS de P. lepidogenys) et sans doute d'une taille supérieure. Pomacentrus spilotoceps est décrit comme une autre espèce nouvelle de Tonga et à partir de photos subaquatiques de Fidji. L'espèce la plus proche semble être P. chrysurus, présent du Pacifique ouest jusqu'aux Maldives. P. spilotoceps se distingue par des taches orange ou jaunes sur l'opercule et avant et au-dessus de la base des pectorales et par branchiospines (contre pour P. chrysurus). Sommario Pomacentrus callainus, già noto come variante cromatica di P. lepidogenys, presente nel Pacifico occidentale, viene descritta sulla base di esemplari raccolti alle isole Tonga e Fiji. Si distingue da P. lepidogenys per la sua completa colorazione verde-blu con una macchia cuneiforme nera alla base superiore della pinna pettorale, per un maggior numero di rastrelli branchiali (22-25, rispetto a in P. lepidogenys), per una maggiore altezza dl corpo ( % SL rispetto a % SL in P. lepidogenys), per le spine dorsali più lunghe (la più lunga è % SL, rispetto al % SL in P. lepidogenys) e probabilmente per avere dimensioni maggiori. Pomacentrus spilotoceps viene descritta come nuova specie sulla base di quattro esemplari raccolti a Tonga e una segnalazione fotografica presso le Isole Fiji. La sua specie più vicina sembra essere P. chrysurus, diffuso dal Pacifico occidentale alle Isole Maldive. P. spilotoceps se ne distingue per la presenza di una macchia arancione o 167 aqua vol. 5 no

2 Two new damselfishes of the genus Pomacentrus from the south-west Pacific gialla sull opercolo e al di sopra e al di sotto della base della pinna pettorale e per avere rastrelli branchiali, rispetto ai in P. chrysurus). Introduction The author collected a pale blue-green Pomacentrus in Fiji in 1971 and another in Tonga in 1983 that had scales on the sub-orbital and the general morphology characteristic of P. lepidogenys, but lacked the yellow normally seen on the median fins of P. lepidogenys. The specimens went on the shelf of the Bishop Museum as P. lepidogenys, but with a question mark. In 1999 the author took underwater photos of the species in Fiji and noted the apparent absence of typical P. lepidogenys. While writing the pomacentrid section for a book on South Pacific fishes, the author made a more detailed examination of these specimens from Fiji and Tonga. A difference in colour from typical P. lepidogenus was noted in the preserved specimens. The black spot at the upper base of the pectoral fin is larger and wedgeshaped, extending about halfway down the base of the fin (the lower, attenuate part is generally more lightly pigmented). This spot is very small in P. lepidogenys, often only dusky, and sometimes wanting, at least in preserved specimens. No differences in fin ray or scale counts could be found from typically coloured P. lepidogenys, but there is a modal shift of one in the number of tubed lateral line scales, and a significant difference in gill raker counts (Table I). The species is therefore described here as new. A second new species of Pomacentrus was collected in Tonga in 1983 and photographed underwater in Fiji in It languished as Pomacentrus sp. at the Bishop Museum until recent closer examination. It is unique in having pale orange or yellow spots on the operculum and anterior to and above the pectoral fin base. Materials and Methods Type specimens of the first-mentioned species were deposited in the Bernice P. Bishop Museum, Honolulu (BPBM); the U.S. National Museum of Natural History, Washington, D.C. (USNM); the Western Australian Museum, Perth (WAM); the Australian Museum, Sydney (AMS); the California Academy of Sciences, San Francisco (CAS); Muséum National d Histoire Naturelle, Paris (MNHN); the National Science Museum, Tokyo (NSMT); and the Royal Ontario Museum, Toronto (ROM). Type specimens of the second species were deposited in the first three institutions listed above. Lengths of specimens are given as standard length (SL), measured from the most anterior end of the upper lip to the base of the caudal fin (posterior end of hypural plate); head length is measured from the same anterior point to the posterior end of the opercular flap; body depth is the maximum depth taken vertically from the base of the dorsal spines; body width is the maximum width just posterior to the gill opening; orbit diameter is the greatest fleshy diameter, and interorbital width the least fleshy width; upper jaw length is taken from the front of the upper lip to the posterior end of the maxilla; caudal peduncle depth is Table I. Meristic data of species of Pomacentrus. Dorsal soft rays Anal soft rays Pectoral rays P. callainus P. lepidogenys P. spilotoceps Tubed lateral line scales P. callainus P. lepidogenys P. spilotoceps 1 3 Upper limb gill rakers Lower limb gill rakers P. callainus P. lepidogenys P. spilotoceps Total gill rakers P. callainus P. lepidogenys P. spilotoceps aqua vol. 5 no

3 John E. Randall the least depth, and caudal peduncle length the horizontal distance between verticals at the rear base of the anal fin and the caudal fin base; lengths of fin spines and rays of the dorsal and anal fins are measured to their extreme bases; caudal fin length is the horizontal length from the posterior end of the hypural plate to a vertical at tip of the longest ray; caudal concavity is the horizontal distance between verticals at the tips of the shortest and longest rays; pectoral fin length is the length of the longest ray; pelvic fin length is measured from the base of the pelvic spine to the tip of the longest soft ray; pectoral ray counts include the upper rudimentary ray; only the tube-bearing anterior lateral line scales are counted; the counts of posterior lateral line scales include tubed, pored, and deeply pitted scales that are in continuous series to the caudal fin base; gill raker counts include all rudiments. Data in parentheses in the descriptions refer to paratypes (when different from the holotype). Ratios of proportional measurements in the text of the diagnoses and descriptions are rounded to the nearest Pomacentrus callainus n. sp. (Figs. 1-2; Tables I, II) Holotype: BPBM 37982, male, 61.8 mm, Tonga, Tongatapu, Hakaumama o Reef; patch reef in lagoon near tower, 3 m, spear, J. E. Randall, 5 March Paratypes: BPBM 11350, 41.7 mm, Fiji, Viti Levu, Rat-tail Pass (first pass west of entrance to Suva Harbor), west side, m, rotenone, J.E. Randall, R.D. Randall, M. Gawel, O. McCauseland, D. Owens, and L. Craighead, 7 August 1971; WAM P , 57.5 mm, same data as preceding; MNHN , 59.4 mm, CAS , 61.0 mm, NSMT-P 63012, 63.7 mm, all with same data as holotype; BPBM 37970, 73.5 mm, Tonga, Tongatapu, Monuafe Island, east side, coral patch, 1.5 m, spear, J. E. Randall, 4 March 1983; AMS I , 66.3 mm, Tonga, Vava u Group, Euakafa Island, south side, reef, m, rotenone, J. E. Randall and K. Okamoto, 14 March 1983; USNM , 73.8 mm, same data as preceding; ROM 48677, 18: mm, Fiji, Dravuni Island, about 300 m off USP field station, coral head, rotenone, R. Winterbottom, A. Emery, T. Emery, J. Payne, and R. McKinnon, 28 March Diagnosis Dorsal rays XIII,13-14 (usually 14); anal rays II,13-15; pectoral rays 17-19; tubed lateral line scales (modally 16); total gill rakers 22-25; sub-orbital scaled, the margin smooth or rarely with one or two weak serrae; body depth in SL; longest dorsal spine in head length; second anal spine in head length; pale blue-green in life with a wedgeshaped black bar at upper pectoral fin base; largest specimen, 73.8 mm SL. Fig. 1. Holotype of Pomacentrus callainus, BPBM 37982, 61.8 mm SL, Tongatapu, Tonga. Photo by J. E. Randall. 169 aqua vol. 5 no

4 Two new damselfishes of the genus Pomacentrus from the south-west Pacific Fig. 2. Underwater photograph of adult Pomacentrus callainus, Tongatapu, Tonga. Photo by J. E. Randall. Description Dorsal rays XIII,14 (13-14, usually 14); anal rays II,14 (13-15); all dorsal and anal soft rays branched, the last to base; pectoral rays 18 (17-19), the upper two and lowermost one or two unbranched; pelvic rays I,5; principal caudal rays 15, the median 13 branched; upper procurrent caudal rays 6 (6-7), the posterior two segmented; lower procurrent caudal rays 7 (7-8), the posterior two segmented; scales in longitudinal series 27; tubed lateral line scales 17 (15-18); posterior mid-lateral scales with a pore or deep pit (in continuous series) 8 (7-8, usually 8); scales above lateral line to origin of dorsal fin 3; scales above lateral line to base of middle dorsal spine 1.5; scales below lateral line to origin of anal fin 8; gill rakers ( ); pseudobranchial filaments of holotype 15; branchiostegal rays 5; supraneural (pre-dorsal) bones 3; vertebrae Body depth 2.05 ( ) in SL; body compressed, the width 2.7 ( ) in body depth; head length 3.35 ( ) in SL; dorsal profile of head nearly straight; snout shorter than orbit, its length 3.5 ( ) in head length; orbit diameter 2.75 ( ) in head; interorbital space nearly flat, its width 2.95 ( ) in head; caudal peduncle depth 1.8( ) in head; caudal peduncle length 2.6 ( ) in head. Mouth small, terminal or with lower jaw slightly projecting, and oblique, at about 45 to horizontal axis of head and body; maxilla nearly or just reaching a vertical at anterior edge of orbit, the upper jaw length 2.95 ( ) in head; front of jaws rounded; teeth incisiform, the tips nearly truncate at front of jaws and rounded to the side; teeth biserial, those of inner row slender, one at each juncture of outer teeth; teeth on each side of upper jaw of holotype 17, and on each side of lower jaw 15. Tongue pointed, set far back in mouth. Gill rakers long and slender, the longest on lower limb near angle about three-quarters length of longest gill filaments. Nostril (no posterior nostril detected) round with a low fleshy rim, directly anterior to middle of eye about two-thirds pupil diameter from edge of orbit. Opercular spine very small, flat, and largely hidden by overlying scale; posterior margin of preopercle serrate, with 23 serrae in holotype, the free edge extending nearly to level of centre of eye (though upper edge hidden by scales); anterior margin of preopercle extending to below corner of mouth; suborbital narrow, free nearly to vertical at posterior edge of orbit, the edge usually smooth (holotype with two small serrae on one side, none on the other); posterior part of pre-orbital twice as deep as sub-orbital, with a small spine at its rounded lower posterior corner. Scales finely ctenoid; head scaled except lips, narrow edge at front of snout (1.6 mm on holotype), and a zone of about pupil diameter across side of snout, containing nostrils in its upper part; a scaly sheath at base of dorsal and anal fins, pupil height posteriorly on spinous portion of dorsal fin, progressively shorter on soft portion; a column of scales on each membrane of dorsal and anal fins, narrowing distally, those on spinous portion of dorsal progressively aqua vol. 5 no

5 John E. Randall longer, reaching nearly three-quarters distance to spine tips on posterior membranes; small scales on soft portion of dorsal fin reaching half way to margin anteriorly and progressively less posteriorly; small scales on caudal fin (when all present) extending about two-thirds distance to posterior margin; small scales on about basal quarter of pectoral fins; a median scaly process extending posteriorly from between base of pelvic fins, its length about threefifths length of pelvic spine; axillary scale above base of pelvic spine about equal in length to median scaly process. Origin of dorsal fin over second lateral line scale, the pre-dorsal length 2.65 ( ) in SL; base of spinous portion of dorsal fin twice as long as base of spinous portion; first dorsal spine 3.1 ( ) in head; second dorsal spine 2.45 ( ) in head; thirteenth dorsal spine longest 1.9 ( ) in head; membranes of spinous portion of dorsal fin incised about half length of spine anteriorly, progressively less posteriorly; a thickened, tapering cirrus extending posteriorly from near tip of each dorsal spine, its pointed tip nearly reaching following spine, supporting membrane below; fifth or sixth dorsal soft ray longest, 4.2 ( ) in SL; origin of anal fin beneath base of tenth dorsal spine, the pre-anal length 1.5 ( ) in SL; first anal spine 2.85 ( ) in head; second anal spine 1.65 ( ) in head; eighth and ninth anal soft rays longest, 3.9 ( ) in SL; caudal fin forked, the lobe tips rounded, its length 2.7 ( ) in SL; caudal concavity 2.35 ( ) in head; fourth pectoral ray longest, 3.2 ( ) in SL; origin of pelvic fins slightly posterior to base of pectoral fins, the prepelvic length 2.35 ( ) in SL; pelvic spine 1.85 ( ) in head; first soft ray of pelvic fin filamentous, just reaching or extending slightly beyond origin of anal fin, 3.4 ( ) in SL. Colour of holotype when fresh (Fig. 1): Purplish grey, tinged with pink on operculum, cheek, pre-pectoral area, and ventrally on body; a blackish streak from chin to ventral edge of preopercle; edge of orbit narrowly blackish; dorsal part of head, body above tubed portion of lateral line, and scaled basal part of spinous portion of dorsal fin dark purplish grey ; outer spinous portion of dorsal fin dark purplish-grey the distal cirri of membranes black; a pale area on each membrane between scaled basal part and outer dark incised part; soft portion of dorsal fin and anal fin coloured like body on basal scaled portion, the rays purplish grey, the membranes dusky yellowish, becoming blackish distally; base of caudal fin dull Table II. Proportional measurements of type specimens of Pomacentrus callainus standard length. expressed as percentages of the Holotype Paratypes BPBM BPBM WAM MNHN CAS NSMT BPBM USNM Standard length (mm) Body depth Body width Head length Snout length Orbit diameter Inter-orbital width Caudal peduncle depth Caudal peduncle length Upper jaw length Pre-dorsal length Pre-anal length Pre-pelvic length First dorsal spine Second dorsal spine Third dorsal spine Longest dorsal spine Longest dorsal ray First anal spine Second anal spine Longest anal ray Caudal fin length broken Caudal concavity Pectoral fin length Pelvic spine length Pelvic fin length aqua vol. 5 no

6 Two new damselfishes of the genus Pomacentrus from the south-west Pacific pink, this colour continuing on rays, the membranes dusky yellow, becoming blackish distally; pectoral fins with purplish grey rays, clear membranes, and a wedge-shaped black spot at upper base; pelvic fins purplish grey tinged with pink, shading to blackish distally and to black on filament. Colour in life (Fig. 2): Light blue-green, the edges of scales dusky; a wedge-shaped black spot on upper part of pectoral fin base; ventral part of head and chest dusky; a dusky bar through middle of eye; outer edge of each spinous membrane of dorsal fin either blue-green or bright blue. Colour of holotype in alcohol: Medium brown, the scale edges a little darker; scaled basal part of dorsal fin coloured like body; outer part of spinous membranes of dorsal fin dark brown to level of indentation of membrane, the tapering distal cirrus very dark brown; a translucent submarginal band below dark brown incised portion of dorsal fin; anal fin medium brown, the anterior and outer edges broadly darker brown; caudal fin brown like body basally, grading to lighter brownish yellow, the distal edge dusky; pectoral fins pale yellowish with a prominent dark brown spot at upper base, narrowing to a line extending threequarters down base; inner base of pectoral rays dusky, darkest dorsally; pelvic fins brown, the first soft ray and adjacent membranes dark brown. Etymology This species is named Pomacentrus callainus from the Latin for blue-green, in reference to its life colour. Remarks The life colour of this species fades very quickly after death, as can be seen by comparing Figures 1 and 2. As mentioned in the Introduction, Pomacentrus callainus was initially identified as P. lepidogenys Fowler & Bean,1928, described from the Philippines. Both share the distinctive feature of a fully scaled suborbital that is smooth or with a few weak serrae on the ventral margin. The most obvious colour difference of P. lepidogenys, as may be seen in Figure 3 of this species, is the broad zone of yellow at the base of the dorsal fin. Also, the base of the caudal is often yellow, as is the base of the anal fin. There is only a very small blackish spot at the upper edge of the pectoral fin base; the outer edge of each spinous membrane of the dorsal fin is black. A slight difference is apparent in Table I in the number of lateral line scales, modally 16 in Pomacentrus callainus and 17 in P. lepidogenys. A more obvious difference is evident from the table in the total number of gill rakers, 22 to 25 in P. callainus and in P. lepidogenys. Table III. Proportional measurements of type specimens of Pomacentrus spilotoceps expressed as percentages of standard length. Holotype Paratypes BPBM WAM MNHN USNM Standard length (mm) Body depth Body width Head length Snout length Orbit diameter Inter-orbital width Caudal peduncle depth Caudal peduncle length Upper jaw length Pre-dorsal length Pre-anal length Pre-pelvic length First dorsal spine broken Second dorsal spine Third dorsal spine Longest dorsal spine Longest dorsal ray broken 23.6 First anal spine Second anal spine Longest anal ray Caudal fin length Caudal concavity Pectoral fin length Pelvic spine length Pelvic fin length aqua vol. 5 no

7 John E. Randall Fig. 3. Underwater photograph of adult Pomacentrus lepidogenys, Solomon Islands. Photo by J. E. Randall. Two morphological differences were found with no overlap. The body depth is greater in Pomacentrus callainus, % SL, compared to % for P. lepidogenys (15 specimens, mm SL). The longest dorsal spine of P. callainus is % SL, compared to % SL in P. lepidogenys. The second anal spine is usually longer in P. callainus as well, % SL, compared to % for P. lepidogenys. There also may be a difference in the maximum size. The largest of 36 specimens of P. lepidogenys from eight lots is 68 mm SL. The largest of the specimens of P. callainus measures 73.8 mm SL. The Bishop Museum has one lot of Pomacentrus. lepidogenys (BPBM 27107, 4: mm) from Kinde Reef, New Caledonia, collected by P. Laboute and J.-L. Menou in 1979 with no record of life colour, but judging from the figure of this species in the book on New Caledonia fishes by Laboute and Grandperrin (2000: 325), the coloration there is typical of the species. However, the number of gill rakers of the four specimens is 22-24, with two counts on 23, the modal count for P. callainus. On the other hand, the lateral line scale count, three with 17 and one with 18, favours P. lepidogenys. The body depth of the four specimens, % SL, is intermediate to P. lepidogenys and P. callainus, and the longest dorsal spine, % SL slightly favours P. callainus. More material is needed from New Caledonia, and especially documentation of the life colour, to determine if there is a population there intermediate in some features to P. lepidogenys and P. callainus. Allen (1991: 149) has added to the complexity by writing with respect to P. lepidogenys, Australian and Melanesian specimens are mainly pale blue-grey whereas throughout the northern part of the range (Indonesia and northwards), the dorsal fin and tail base are bright yellow. However, his figure of P. lepidogenys, with yellow on the dorsal and caudal fins, is from the Great Barrier Reef, and he illustrated still another (Allen, 1975: 213, upper fig.) from the southern Great Barrier Reef with the same yellow-finned coloration. Note, in addition, that the illustration of P. lepidogenys in the present paper is from the Solomon Islands, part of Melanesia. The lower figure on page 213 of Allen (1975), also from the Great Barrier Reef, is evidently the pale blue-grey phase of P. lepidogenys that he mentioned as the dominant colour form. This figure has no dark spot at the upper base of the pectoral fin. Clearly more study is needed of P. lepidogenys in the western part of its range. There may be two species and not two colour phases. Material of Pomacentrus lepidogenys examined: RYUKYU ISLANDS: Ishigaki, BPBM 6874, 2: mm: BPBM 6879, 60 mm; BPBM 7439, 9:40-63 mm. PHILIPPINES: Siquijor, ROM 54604, 29: mm. SOLOMON ISLANDS: Florida Island, BPBM 15660, 3: mm. GREAT BARRIER REEF: Lizard Island, ROM 51291, 36 mm; ROM 51295, 48.5 mm; ROM 51322, 33 mm. Capricorn Group, One Tree Island, ROM 59495, 3: mm. 173 aqua vol. 5 no

8 Two new damselfishes of the genus Pomacentrus from the south-west Pacific Pomacentrus spilotoceps n. sp. (Figs. 4, 5; Tables I, III) Holotype: BPBM 37983, male, 60.0 mm, Tonga, Tongatapu, Hakaumama o Reef, patch reef in lagoon near tower, 3 m, spear, J. E. Randall, 5 March Paratypes: MNHN , 59.6 mm, USNM , 67.3 mm, and WAM P , 59.2 mm, all with same data as holotype. Diagnosis Dorsal rays XIII,14-15 (usually 15); anal rays II,15; Fig. 4. Holotype of Pomacentrus spilotoceps, BPBM 37893, 60.0 mm SL, Tongatapu, Tonga. Photo by J. E. Randall. Fig. 5. Underwater photograph of adult of Pomacentrus spilotoceps, Viti Levu, Fiji. Photo by J. E. Randall. aqua vol. 5 no

9 John E. Randall pectoral rays 18; tubed lateral line scales (usually 18); total gill rakers 22-24; sub-orbital naked, the margin serrate; posterior edge of pre-orbital with a strong retrorse spine; body depth in SL; longest dorsal spine in head length; second anal spine in head length; yellowish brown, the scale edges blackish; dull yellow to pale orange spots on opercle and anterior to and above pectoral fin base; two blue lines on side of snout crossing upper lip; a small vertically elongate deep blue or black spot at upper end of gill opening, and a small black spot at upper pectoral fin base; ocellus posteriorly in lower half of dorsal fin present or absent in adults; caudal fin abruptly yellowish. Description Dorsal rays XIII,15 (14-15); anal rays II,15; all dorsal and anal soft rays branched, the last to base; pectoral rays 18, the upper two and lowermost unbranched; pelvic rays I,5; principal caudal rays 15, the median 13 branched; upper procurrent caudal rays 6, the posterior two segmented; lower procurrent caudal rays 7, the posterior two segmented; scales in longitudinal series 27; tubed lateral line scales 17 (18); posterior mid-lateral scales with a pore or deep pit (in continuous series) 8 (7-9); scales above lateral line to origin of dorsal fin 3; scales above lateral line to base of middle dorsal spine 1.5; scales below lateral line to origin of anal fin 8; gill rakers ( ); pseudobranchial filaments of 59.2-mm paratype 13; branchiostegal rays 5; supraneural (pre-dorsal) bones 3; vertebrae Body depth 2.0 ( ) in SL; body compressed, the width 2.8 ( ) in body depth; head length 3.15 ( ) in SL; dorsal profile of head nearly straight; snout length 3.3 ( ) in head length; orbit diameter 3.25 ( ) in head; interorbital space slightly convex, its width 3.45 ( ) in head; caudal peduncle depth 2.0 ( ) in head; caudal peduncle length 3.05 ( ) in head. Mouth small, terminal, and slightly oblique, forming an angle of about 20 to horizontal axis of head and body; maxilla nearly or just reaching vertical at anterior edge of orbit, the upper jaw length 3.35 ( ) in head; front of jaws rounded; teeth in jaws slender, incisiform with rounded tips, slightly incurved, and biserial, those of inner row twice as slender, each at gap between two outer teeth; total upper jaw teeth of outer row of holotype 45 and total for lower jaw 42. Tongue pointed, set far back in mouth. Gill rakers long and slender, the longest on lower limb near angle nearly as long as longest gill filaments. No posterior nostril detected. Nostril round with a low fleshy rim, directly anterior to middle of eye, about two-thirds pupil diameter from edge of orbit. Opercular spine at level of lower edge of orbit, small and flat, only its tip projecting from beneath most posterior scale on opercle; posterior margin of preopercle strongly serrate, the serrae angled upward, progressively shorter dorsally, 25 on holotype; posterior margin of preopercle extending slightly dorsal to level of centre of eye (though upper edge hidden by scales); anterior margin of preopercle extending to below corner of mouth; sub-orbital irregularly serrate; pre-orbital twice as deep as sub-orbital, with a large retrorse spine on its posterior edge. Scales finely ctenoid; head scaled except suborbital, pre-orbital, lips, and a narrow edge at front of snout about one-half pupil diameter in width; a scaly sheath at base of spinous and anterior soft portions of dorsal and anal fins, pupil height posteriorly on spinous portion of dorsal fin; a column of scales on each membrane of spinous portion of dorsal fin, narrowing distally, reaching two-thirds to three-quarters distance to spine tips; small scales extending out on anterior soft portion of fin nearly three-quarters distance to margin, then progressively shorter posteriorly; small scales on anal fin extending more than three-quarters distance to margin except posteriorly; small scales on caudal fin, when intact, extending about three-quarters distance to posterior margin; small scales on about basal quarter of pectoral fins; a median scaly process extending posteriorly from between base of pelvic fins, its length about two-thirds length of pelvic spine; axillary scale above base of pelvic spine nearly three-quarters length of pelvic spine. Origin of dorsal fin over base of third lateral line scale, the pre-dorsal length 2.65 (2.7) in SL; base of soft portion of dorsal fin nearly half as long as base of spinous portion; first dorsal spine 3.2 ( ) in head; second dorsal spine 2.8 ( ) in head; thirteenth dorsal spine longest (but eleventh and twelfth nearly as long), 1.6 ( ) in head; membranes of spinous portion of dorsal fin incised only posteriorly, about half length of spine at front of fin, progressively less posteriorly; membrane from tip of each spine of dorsal fin extending horizontally behind, supported by a slender thickening, ending posteriorly in a point; eighth and ninth dorsal soft rays longest, 4.2 ( ) in SL; origin of anal fin below base of eleventh dorsal spine, the pre-anal length 1.5 in SL; first anal spine 2.85 (2.8) in head; second anal spine 1.5 ( ) in head; ninth and tenth anal soft rays longest, 4.1 ( ) in SL; caudal fin forked, the lobe tips slightly rounded, its length 3.15 ( ) in SL; caudal concavity 2.95 ( ) in head; fourth pectoral ray longest, 3.35 ( ) in SL; origin of pelvic fins below lower base of pectoral fins, the pre-pelvic length 2.45 (2.4) in SL; pelvic spine 1.8 ( ) in head; first soft ray of pelvic fins just reaching anus in holotype, prolonged as a short filament in paratypes, nearly reaching or just reaching origin of anal fin, 4.05 ( ) in SL. Colour of holotype when fresh (Fig. 4): Yellowish brown, the scale edges blackish; a large pale orange spot on each scale of opercle, pre-pectoral area, and on three scales above pectoral fin base, the lowest 175 aqua vol. 5 no

10 Two new damselfishes of the genus Pomacentrus from the south-west Pacific notably large and sub-triangular; two blue lines on side of snout crossing upper lip, and a parallel one below posterior end of maxilla; blue dots on postorbital head, tending to form lines, one of which continues as an oblique row of five scales on nape, the dot on each enlarged to a blue blotch; a small vertically elongate black spot at upper end of gill opening, and a small black spot at upper pectoral fin base; an oblong black spot, narrowly rimmed in blue, posteriorly in dorsal fin; upper edge of each inter spinous membrane of dorsal fin bright blue with a sub-marginal brownish orange line; a longitudinal blue line in spinous portion of fin just above basal scaled part; anal fin with a narrow blue margin, a narrow blue band in outer third of fin with a proximal row of four blue spots, one per membrane, and a faint bluish streak on last six rays of fin; caudal fin abruptly yellowish brown basally, shading to pale yellowish distally; pectoral fins with transparent membranes and brown-edged yellow rays; pelvic fins yellowish brown, the spine darker brown with a pale blue edge. Colour in life of an adult from Fiji (Fig. 5): Similar to the above, but spots on opercle and around upper part of pectoral fin base more yellow than orange, and blue markings absent except anterior edge of dorsal fin ocellus and margins of dorsal and anal fins. Colour of holotype in alcohol: Brown, the scale edges dark brown; centres of scales on opercle lighter brown than edges; a vertically elongate black spot of nearly pupil diameter in length at upper end of gill opening; a round black spot of about half pupil diameter at upper base of pectoral fins; axil of pectoral fins not black; a pale-edged black spot in dorsal fin between tenth and thirteenth soft rays, about onethird way out in fin; naked spinous part of dorsal fin below incised portion lighter brown than rest of fin, thus appearing as a pale longitudinal band; caudal fin abruptly light yellowish brown. Etymology This species is named Pomacentrus spilotoceps from the Greek spilotos for spotted and ceps short for head, in reference to the orange or yellow spots on the head, its most characteristic markings. Remarks Juveniles were not observed, but it is presumed they had bright blue lines and small spots on the head, as is often seen on species of Pomacentrus. Vestiges of these persisted in the 60-mm holotype, a mature male, when first collected. This species was only rarely encountered in Tonga and Viti Levu. It occurred on shallow coral reefs in calm areas. Of the known species of Pomacentrus, P. spilotoceps seems most similar to P. chrysurus Cuvier which ranges from New South Wales and the Great Barrier Reef north to the Ryukyu Islands, east to New Caledonia and Palau, and west to the Maldives. It has the same fin-ray counts, white to yellow caudal fin, the same upper black spot on the opercle and on the pectoral fin base, two oblique blue lines on side of snout, and it can retain an ocellus posteriorly in the dorsal fin to adult size (though higher on the fin). P. spilotoceps differs in having instead of tubed lateral line scales, but this slight difference may disappear when more specimens are available. More significant is the gill raker difference, for spilotoceps compared to for chrysurus. The most obvious colour difference, other than the orange or yellow spots anteriorly on spilotoceps, is the more strongly contrasting white or yellow caudal fin of chrysurus. The juvenile of chrysurus is bright yellow on the broad upper part of the head and body and dorsal fin to the ocellus, with no blue markings within. As mentioned, the blue markings dorsally on the head and nape of the holotype of spilotoceps probably indicate better developed, brighter blue markings on juveniles. Acknowledgements Richard Winterbottom and Marty Rouse of the Royal Ontario Museum are thanked for the very helpful loan of Pacific specimens of Pomacentrus. Thanks are also due Arnold Y. Suzumoto and Loreen R. O Hara of the Bishop Museum for curatorial assistance and X-rays. References Allen, G. R Damselfishes of the South Seas. T.F.H. Publications, Neptune City, New Jersey, 240 pp. Allen, G. R Damselfishes of the World. Aquarium Systems, Mentor, Ohio, 271 pp. Fowler, H. W. & B. A. Bean Contribution to the biology of the Philippine Archipelago and adjacent regions. The fishes of the families Pomacentridae, Labridae, and Callyodontidae, collected by the United States Bureau of Fisheries steamer Albatross, chiefly in Philippine seas and adjacent waters. Bulletin of the United States National Museum. 100, volume 7: viii +525 pp. Laboute, P. & R. Grandperrin Poissons de Nouvelle-Calédonie. Editions Catherine Ledru, Nouméa, 520 pp. aqua vol. 5 no