Phallic Catshark

description

Description. Body very slender, head height 7.0 (7.1 – 8.5) % TL; abdomen long, pectoral to pelvic space 14.2 (10.9 – 16.6) % TL, 1.43 (1.12 – 1.68) of head length; pelvic to anal space long 1.14 (0.98 – 1.43) of anal-fin base; caudal peduncle elongate, anal to caudal space 0.71 (0.59 – 0.96) of anal-fin base; peduncle not greatly compressed, width 1.42 (1.31 – 2.00) in height. Snout long parabolic, tip narrowly rounded; preoral length 7.9 (6.9 – 7.4) % TL, 1.01 (0.93 – 1.06) times mouth width; prenarial snout 1.52 (1.14 – 1.66) times eye length. Eyes small, length 3.3 (2.6 – 3.5) % TL, 6.15 (5.31 – 7.11) in head length in adults; eyes dorsolateral on head, with well-developed subocular ridges. Mouth moderately large and long, broadly arched, width 7.8 (6.9 – 8.2) % TL, 2.44 (1.94 – 2.88) times its length; labial furrows well developed, lower furrows only slightly shorter than mouth length, not extending forward to symphysis. Teeth with 3 – 5 cusps, mainly tricuspidate in holotype and other adults; cusps adjacent central cusp well developed, about half length (slightly less at centre of mouth) of central cusp, more than half in young; in 60 (57) rows in upper jaw; 60 rows in lower

Galeus priapus sp. nov., a new species of sawtail catsharks (Carcharhiniformes: Scyliorhinidae) from New Caledonia

diagnosis

Diagnosis. A small, slender Galeus with the following combination of characters: claspers extremely long and slender in adult males, distal tips extending to near anal origin or beyond, their outer length 9.2 – 11.2 % TL, 7.2 – 8.7 times base width; clasper without hooks or spiny denticles; exorhipidion greatly elongated, about 4 times spiracle length when fully developed; anterior inner margin of pelvic fin not fused to clasper; anal fin relatively small, length 9.8 – 12.0 % TL; posterior anal-fin margin 4.7 – 5.9 % TL, 1.4 – 1.8 in anterior margin of second dorsal fin; prepectoral length relatively short, about 17.8 – 19.4 % TL; labial furrows moderately long, not confined to mouth corners; enlarged denticle crest of upper caudal fin originating almost over origin of ventral caudal lobe, no abrupt demarcation between denticles of crest and those of caudal peduncle; denticles forming 2 – 5 central rows of denticles between larger oblique lateral rows near crest origin; no subcaudal crest; anterior margin of pectoral fin black; anterior half of dorsal fins almost entirely dark or dusky; precaudal centra 81 – 86.

Galeus priapus sp. nov., a new species of sawtail catsharks (Carcharhiniformes: Scyliorhinidae) from New Caledonia

discussion

Remarks. This species is almost identical in general appearance and colour to G. gracilis. Comparisons of morphometric data from the type series of G. gracilis with those of P. priapus showed the following differences: the caudal-fin of P. priapus is longer (length of ventral caudal lobe 22 % versus 20 %); the anal fin is smaller (length 9.6 – 12.0 % versus 12.4 – 13.8 % TL; posterior anal-fin margin 4.6 – 5.9 % versus 6.4 – 7.3 % TL, 1.4 – 1.8 versus 1.1 – 1.2 in anterior margin of second dorsal fin; the pelvic-anal space is greater (10.0 – 11.7 % versus 8.0 – 10.3 %) and the prepectoral length is slightly shorter (17.8 – 19.4 versus 19.2 – 21.5 % TL). The denticles on the upper caudal crest of P. priapus are less distinct anteriorly, originate more posteriorly, and are represented in more rows (mainly in 2 – 3 central rows anteriorly versus mainly 1). Also, the dorsal fins are mostly dark (rather than being mostly pale distally) and there are more vertebrae (precaudal centra 81 – 86 versus 74 – 78). Major differences exist in clasper structure: the claspers are extremely long (outer length 9.2 – 11.2 versus 5.2 – 7.3 % TL in G. gracilis (Compagno and Stevens, 1993, give 10.3 – 10

Galeus priapus sp. nov., a new species of sawtail catsharks (Carcharhiniformes: Scyliorhinidae) from New Caledonia

distribution

Distribution. Known from the marginal slopes off southern New Caledonia, south of the Loyalty Islands Ridge and north of the Norfolk Ridge in 620 – 830 m depth and off Espiritu Santo Island (Vanuatu) in 262 – 352 m depth.

Galeus priapus sp. nov., a new species of sawtail catsharks (Carcharhiniformes: Scyliorhinidae) from New Caledonia