| Phallic catshark | |
|---|---|
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Subclass: | Elasmobranchii |
| Division: | Selachii |
| Order: | Carcharhiniformes |
| Family: | Pentanchidae |
| Genus: | Galeus |
| Species: | G. priapus |
| Binomial name | |
| Galeus priapus | |
Thephallic catshark (Galeus priapus) is a species ofshark belonging to thefamilyPentanchidae, the deepwater catsharks. It is found on or near the ocean floor, in the deep waters offNew Caledonia andVanuatu. A slender species attaining a length of 46 cm (18 in), it is characterized by a longcaudal fin bearing a crest of enlargeddermal denticles along the dorsal margin, and very longclaspers in adult males. This shark is gray-colored, with four dark saddles along the back and tail.
The first specimens ofG. priapus were collected in the 1990s, during a series ofIndo-Pacific research cruises jointly undertaken by theInstitut de recherche pour le développement (IRD) and theMuséum national d'histoire naturelle (MNHN). Bernard Séret and Peter Last described the new species in a 2008 volume of thescientific journalZootaxa. It was given thespecific epithetpriapus after theGreek fertility godPriapos, in reference to the distinctively longclaspers of males. Thetype specimen is a 39 cm (15 in) long adult maletrawled by the RVAlis off New Caledonia on March 30, 1994. Within the genus, this species most closely resembles theslender sawtail catshark (G. gracilis).[2]
Galeus priapus is ademersal species that has been recorded from a depth of 620–830 m (2,030–2,720 ft) on the slopes ofseamounts and submarine ridges off New Caledonia, between theLoyalty Islands and theNorfolk Ridge, as well as from a depth of 262–352 m (860–1,155 ft) offEspiritu Santo Island inVanuatu.[2]
Galeus priapus is a firm-bodied, very slim shark that reaches at least 46 cm (18 in) in length. The head has a long, narrowparabolic shape from above. The small, horizontal eyes are placed rather high on the head, and equipped with rudimentarynictitating membranes (protective third eyelids). Beneath each eye is a prominent ridge, and behind is a tinyspiracle. The anterior rims of the nostrils bear triangular flaps of skin. The mouth is fairly large and wide, and is broadly arched. There are long, well-developed furrows that wrap around each corner of the mouth. The tooth rows number around 60 in either jaw; the teeth have a narrow central cusp flanked by 1–2 pairs of smaller cusplets. There are five pairs ofgill slits.[2]
Thedorsal fins vary in shape, with the first is marginally larger than the second. The first dorsal fin originates over the posterior half of thepelvic fins, while the second originates over the middle of theanal fin. Thepectoral fins are fairly large and wide, with rounded tips. The pelvic fins are short and low; adult males have characteristically long, thinclaspers measuring roughly 10–11% of the total length. The anal fin is relatively small, with its base measuring 8–10% of the total length. Thecaudal fin is long, with a small lower lobe and a deep ventral notch near the tip of the upper lobe. Thedermal denticles are small and overlapping, each with a median ridge and three marginal teeth on the crown. An elevated, saw-like crest of enlarged denticles is present along the front half of the dorsal caudal fin edge. This species is a variable shade of gray above, with a dark saddle intersecting the front half of each dorsal fin, and two more saddles along the tail. The leading margins of the pectoral fins are distinctly black, while the trailing margins of the dorsal and anal fins are whitish. The underside is pale and unmarked. The interior lining of the mouth is blackish on the roof and white elsewhere.[2]
Little is known of the natural history ofG. priapus. Males attainsexual maturity at around 39 cm (15 in) long.[2]
G. priapus has been evaluated asLeast Concern by theInternational Union for Conservation of Nature (IUCN).[3]
