If so, their photophores may also allow individual sharks in a group to keep sight of and coordinate with their cohorts. This shark is caught sporadically, but in large numbers at a time, suggesting they may travel in schools. Like many other bioluminescent, deep-sea sharks, it has a yellow spot over its pineal gland that acts as a "window" for the detection of ambient light levels. The ventrally positioned photophores of the green lanternshark may serve to disguise its silhouette from potential predators via counter-illumination. Biology and ecology A green lanternshark pup alongside an adult These black markings contain numerous light-emitting photophores. The dorsal coloration is dark brown to gray the undersides of the body and snout are black, with a broad, black marking above and behind each pelvic fin, and thin, black marks on the tail. The dermal denticles on the sides of the body are stout and thorn-shaped, widely spaced without any regular pattern the snout is mostly covered by denticles. The caudal fin is low and narrow, with an indistinct lower lobe and an upper lobe about as long as the head. The second dorsal fin also bears a spine in front and is over twice as large as the first in area, with the span between it and the first dorsal fin approximately equal to the distance between the snout tip and first gill slit. The first dorsal fin bears a spine in front and originates over the trailing margin of the broad and rounded pectoral fins. The five pairs of gill slits are very short, comparable to the spiracle in size. The lower jaw contains 24–32 tooth rows, their bases interlocking to form a continuous cutting surface and each tooth bearing a horizontal narrow cusp. There are 29–34 tooth rows in the upper jaw, each tooth with a narrow central cusp flanked by fewer than three pairs of lateral cusplets. The nostrils are preceded by short skin flaps. The eyes are very large and oval in shape. Description The black ventral markings of the green lanternshark contain light-emitting photophores.Ī slim-bodied shark with a short, blunt snout and a long, narrow tail, the green lanternshark attains a maximum known length of 26 cm (10 in). This largely bottom-dwelling species has been caught at depths of 196–915 m (643–3,002 ft), with most individuals being found deeper than 350 m (1,150 ft). In the Caribbean Sea, it is found off Honduras and Nicaragua, and from Panama to Venezuela and perhaps as far as Brazil. In the Gulf of Mexico, it occurs from Texas to Florida and Cuba, and off the Yucatan Peninsula. The range of the green lanternshark is restricted to the upper continental slopes of the western central Atlantic. The specific epithet virens is Latin for "green". The type specimen was a 20.3-cm-long male caught at a depth of 403 m (1,322 ft) in the northern Gulf of Mexico. Schroeder, and Stewart Springer, in the Bulletin of the Museum of Comparative Zoology at Harvard University. The green lanternshark was scientifically described in 1953 by Henry B. This relatively common shark is an occasional, valueless bycatch of commercial fisheries currently it does not appear to be significantly threatened by human activities. Reproduction is aplacental viviparous, with females giving birth to litters of one to three young. Green lanternsharks are thought to be gregarious and may attack their prey, squid and octopus often larger than themselves, in packs. It is dark brown or gray with ventral black coloration, which contain light-emitting photophores that may serve a cryptic and/or social function. Reaching 26 cm (10 in) in length, the green lanternshark has a slender body with a long, thin tail and low, conical dermal denticles on its flanks. This species usually occurs on the upper continental slope below a depth of 350 m (1,150 ft). The green lanternshark ( Etmopterus virens) is a species of dogfish shark in the family Etmopteridae, found in the western central Atlantic Ocean.
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