Perhaps the smallest living shark species, male dwarf lantern-sharks mature at a length of 16–17.5 cm (6.3–6.9 in) and females from a length of 15.5 cm (6.1 in) with 19–20 cm (7.5–7.9 in) long pregnant individuals known. The largest known individual is 21.2 cm (8.3 in) long.
#Dwarf lantern shark Patch
This shark is dark brown with a striking and distinctive pattern of black markings on its ventral surface, a continuous or broken, fine black line along the middle of its back (but without a white band like in the similar Caribbean lanternshark), a black band on the end of its caudal fin, and a dark blotch on its lower caudal fin lobe.Ĭuriously, some of the ventral black markings are composed of light-producing photophores, while others (including the patch behind the pelvic fins) are composed of pigment-containing chromatophores.
#Dwarf lantern shark skin
The skin is densely covered by thin, needle-like dermal denticles in a random pattern, except for the lips and the tips of the fins.
The caudal fin is low, with a moderate lower lobe and a ventral notch near the tip of the upper lobe. The second dorsal fin has twice the area of the first and is larger than the pectoral or pelvic fins, and originates over the end of the pelvic fin bases. The first dorsal fin originates over the trailing margins of the pectoral fins. The trunk is short, with two relatively closely spaced, large dorsal fins bearing grooved spines in front. Scattered, sparse papillae are inside the mouth and on the edges of the gill arches. The lower teeth each have a single, strongly oblique cusp, and their bases are interlocked to form a continuous cutting surface. The upper teeth of adult males have a single cusp flanked by two pairs of smaller cusplets, while the upper teeth of females are more robust and have only one pair of lateral cusplets flanking the central cusp. There are 25–32 tooth rows in the upper jaw and 30–34 tooth rows in the lower jaw. The nares are large and preceded by poorly developed flaps of skin. The eyes are large, twice as long as high, with the anterior and posterior corners acute. It has a long, wide, flattened head comprising a fourth to a fifth of its total length. The dwarf lanternshark appears to reach a maximum length of about 20 cm (7.9 in) (female). This shark apparently inhabits the upper continental slope at a depth of 283–439 m (928–1,440 ft). decacuspidatus) in having irregularly arranged, needle-shaped dermal denticles.Īt present, the dwarf lanternshark has only been reported from a small area of the Caribbean Sea off the coasts of Colombia and Venezuela, occurring between Barranquilla and Santa Marta, near the Guajira Peninsula, and between the Los Testigos Islands and Grenada. gracilispinis), and combtooth lanternshark ( E. This species is grouped with the velvet belly lantern shark ( E. The type specimen is a 18.2 cm (7.2 in) long female caught in the Caribbean Sea off the coast of Colombia. Gilbert, and published their findings in a 1985 Copeia paper. They dubbed the new species in honor of noted shark biologist Perry W.
Fish and Wildlife Service research ship Oregon in 1964. Burgess described the dwarf lantern-shark from specimens collected via trawling by the U.S. His close relatives is the Caribbean Velvey Belly Lantern-Shark, Fringefrin Brown Lantern-Shark and Comb-Tooth Broad-Banded Lantern-Shark.Īmerican ichthyologists Stewart Springer and George H. The dwarf lantern-shark is not significant to commercial fisheries, but could be threatened by mortality from bycatch the degree of impact from human activities on its population is unknown.
Reproduction is aplacental viviparous, with females gestating two or three young at a time. Like other members of its genus, it is capable of producing light from a distinctive array of photophores. This species can be identified by its small size at maturity, long flattened head, and pattern of black ventral markings and a mid-dorsal line. It is known to be present only on the upper continental slopes off Colombia and Venezuela, at a depth of 283–439 m (928–1,440 ft). The dwarf lantern-shark ( Etmopterus perryi) is a little-known species of dogfish shark in the family Etmopteridae and possibly the smallest shark in the world, reaching a maximum known length of 20 cm (7.9 in).
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