![]() ![]() The juvenile coloration is also the origin of the common name "zebra shark". The specific epithet fasciatum means "banded", referring to the striped pattern of the juvenile. The genus name is derived from the Greek stego meaning "covered", and stoma meaning "mouth". As the name proposed by Forster in 1781 has been used in tens of publications since 1899, it is not a nomen oblitum. ![]() Consequently, the former and older is the valid name (as Stegostoma tigrinum), while the latter and younger is its junior synonym. Squalus tigrinus was described by Forster in 1781, two years before Squalus fasciatus was described by Hermann. This name was omitted in Compagno's review in 1984, possibly due to confusion over its year of description (in a publication in 1941, Fowler mistakenly listed it as being described in 1795). A taxonomic review in 2019 instead argued that S. varium are currently in usage for this species until the early 1990s most authorities used the latter name, but since then most have followed Compagno and used the former name. In Compagno's view, the first proper usage of "varius/m" was by Garman in 1913, making it a junior synonym. In 1984, Compagno rejected the name "varius/m" in favor of "fasciatus/m" for the zebra shark, because Seba did not consistently use binomial nomenclature in his species descriptions (though Squalus varius is one that can be construed as a binomial name). Müller and Henle placed this species in the genus Stegostoma in 1837, using the specific epithet fasciatus (or the neuter form fasciatum, as Stegostoma is neuter while Squalus is masculine) from an 1801 work by Bloch and Schneider. No type specimen was designated, though Seba included a comprehensive description in Latin and an accurate illustration of a juvenile. The zebra shark was first described as Squalus varius by Seba in 1758 (Seba died years earlier the publication was posthumous). ![]() There is evidence that its numbers are dwindling.Įarly taxonomists thought that juvenile zebra sharks were a different species because of their different appearance from adults. The World Conservation Union has assessed this species as Endangered worldwide, as it is taken by commercial fisheries across most of its range (except off Australia) for meat, fins, and liver oil. Innocuous to humans and hardy in captivity, zebra sharks are popular subjects of ecotourism dives and public aquaria. The zebra shark is oviparous: females produce several dozen large egg capsules, which they anchor to underwater structures via adhesive tendrils. Though solitary for most of the year, they form large seasonal aggregations. At night, they actively hunt for molluscs, crustaceans, small bony fishes, and possibly sea snakes inside holes and crevices in the reef. Zebra sharks are nocturnal and spend most of the day resting motionless on the sea floor. This species attains a length of 2.5 m (8.2 ft). Young zebra sharks under 50–90 cm (20–35 in) long have a completely different pattern, consisting of light vertical stripes on a brown background, and lack the ridges. Adult zebra sharks are distinctive in appearance, with five longitudinal ridges on a cylindrical body, a low caudal fin comprising nearly half the total length, and usually a pattern of dark spots on a pale background. It is found throughout the tropical Indo-Pacific, frequenting coral reefs and sandy flats to a depth of 62 m (203 ft). The zebra shark ( Stegostoma tigrinum) is a species of carpet shark and the sole member of the family Stegostomatidae. Squalus pantherinus Kuhl & van Hasselt, 1852 Martina Nicolls is the author of Similar But Different in the Animal Kingdom and other books. ![]() Their lifespan has been estimated to be 25–30 years. The colour pattern is dark-brown above and light-yellow below, with vertical yellow stripes and spots. So, young Zebra Sharks have stripes, but adult Zebra Sharks have spots. Young Zebra Sharks, called hatchlings, have a completely different pattern than their parents, consisting of light vertical stripes on a brown background. The female lays up to 46 egg capsules which anchor onto plants and objects in the water. The Zebra Shark is usually solitary or it forms small groups of 20-50 individuals. It hunts at night for food, such as fish, snails, crabs, octopus, squid, and sea snakes. Its slender, flexible body enables it to wriggle into narrow holes and crevices in search of food. During the day, it rests motionless on the sea floor. It is benthic, which means that it is a bottom-dweller. It is found in tropical waters in the Indian Ocean and the Pacific Ocean. It grows to 250 centimetres (98 inches) in length. ![]()
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