![]() ![]() Females produce an average of 10 young per reproductive cycle. This species is ovoviviparous, with the developing embryos being sustained by a yolk sac. The smooth lanternshark feeds on squid, lanternfishes, smaller dogfish sharks, and fish eggs, as well as crustaceans and fish. Biology and ecology Īdult smooth lanternsharks have sexually dimorphic upper teeth. The two species differ in a number of anatomical characteristics, but can be most reliably distinguished by the number of turns in their spiral valve intestines (10–13 in E. The smooth lanternshark is very similar to but smaller than the blurry lanternshark, attaining a length of 50 cm (20 in). ![]() The coloration is a uniform dark brown, with a faint black mark over the bases of the pelvic fins extending both forward and backward on the flank. The skin is covered by many widely spaced, small blocky denticles not arranged in regular rows, giving it a smooth appearance. The caudal fin is short and broad, with a well-developed lower lobe and a ventral notch near the tip of the upper lobe. The pelvic fins are low and angular, and there is no anal fin. The second dorsal fin is much larger than the first and has a longer spine. The first dorsal fin bears a stout spine in front and originates over the free rear tips of the rounded pectoral fins. The lower teeth are smooth, knife-like, and angled, with their bases interlocking to form a continuous cutting surface. Each upper tooth has a narrow smooth-edged central cusp flanked by 1–2 tiny cusplets mature males over 38 cm (15 in) long grow additional pairs of lateral cusplets with age. There are 22–31 tooth rows in the upper jaw and 30–53 tooth rows in the lower jaw. Lightly built, the smooth lanternshark has a large head with a pointed snout, large oval eyes, and nostrils with short anterior skin flaps. The smooth lanternshark has a bulbous snout and large oval eyes. ![]() It has been observed swimming over fields of hydrothermal vents. In the South Atlantic, this shark also inhabits the open ocean from the surface to a depth of 708 m (2,323 ft). Catch data off southern Portugal suggest this species has a preference for rocky substrates, and may conduct a diel vertical migration. Smooth lanternsharks are usually found on or near the bottom on continental and insular shelves and slopes at depths of 274–1,000 m (899–3,281 ft), and possibly to as deep as 1,998 m (6,555 ft). In the Pacific Ocean, it has been reported from the East China Sea to southern Japan, in the Hawaiian–Emperor seamount chain area, off Australia and New Zealand, and over the Nazca Plate (including the Amber Seamount and off Isla Salas y Gómez). In the Indian Ocean, it is found off KwaZulu-Natal and Madagascar. In the Atlantic Ocean, the smooth lanternshark occurs from the Gulf of Mexico to Argentina in the west, Portugal to South Africa (including Cape Verde and the Azores) in the east, and on the Mid-Atlantic Ridge. bigelowi) these two species are distinguished from other lantern sharks by their irregularly arranged, truncated (ending in a flat crown as though the tip were cut off) dermal denticles. The smooth lanternshark forms a species group with the blurred lanternshark ( E. The specific epithet pusillus means "weak" in Latin. This species was later moved to the genus Etmopterus. The first scientific description of the smooth lanternshark, as Acanthidium pusillum, was published by British biologist Richard Thomas Lowe, in an 1839 issue of the scientific journal Transactions of the Zoological Society of London. The International Union for Conservation of Nature (IUCN) has evaluated this species as of Least Concern because of its wide distribution and limited threats.Įarly illustration of a smooth lanternshark, from A history of the fishes of Madeira (1843). Smooth lanternsharks are often caught as bycatch in eastern Atlantic and Japanese commercial fisheries. This slow-growing, ovoviviparous shark feeds on smaller squid, fishes, and fish eggs. This species has a slender, dark brown body with an indistinct black band on the sides over the pelvic fins, and reaches 50 cm (20 in) in length. bigelowi), both of which are distinguished from other members of their family by small, irregularly arranged dermal denticles with a truncated shape. The smooth lanternshark forms a species group with the larger blurred lanternshark ( E. It inhabits benthic environments at a depth of 274–1,000 m (899–3,281 ft), and pelagic environments at a depth of 0–708 m (0–2,323 ft). The smooth lanternshark or slender lanternshark ( Etmopterus pusillus) is a species of dogfish shark in the family Etmopteridae, found widely in the Atlantic and Pacific Oceans. ![]() Etmopterus frontimaculatus Pietschmann, 1907 ![]()
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