The lizard catshark (''Schroederichthys saurisqualus'') is a small

shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimo ...

species of the

catshark Catsharks are ground sharks of the family Scyliorhinidae. They are the largest family of sharks with around 160 species placed in 17 genera. Although they are generally known as catsharks, some species can also be called dogfish due to previous n ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

, Scyliorhinidae, found off the coast of southern

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

on the upper continental shelf at depths of between .

Description

The lizard catshark is a small species growing to a maximum size of for males and for females. It is similar in appearance to the slender catshark (''Schroederichthys tenuis'') but can be distinguished from it by the fact that it has white spotting, a longer distance between the two dorsal fins and a longer distance between the pelvic and anal fins. The dermal denticals on its skin are rounded rather than pointed and it has about 122

vertebra The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic ...

e while the slender catshark has only about 110.

Distribution and habitat

The lizard catshark is native to the Atlantic coast of South America where it is present off Brazil. It is found on the upper part of the continental slope at depths of between among deepwater reefs where there are

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...

s, tube sponges, gorgonians,

crinoid Crinoids are marine animals that make up the class Crinoidea. Crinoids that are attached to the sea bottom by a stalk in their adult form are commonly called sea lilies, while the unstalked forms are called feather stars or comatulids, which are ...

s and

brittle star Brittle stars, serpent stars, or ophiuroids (; ; referring to the serpent-like arms of the brittle star) are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their flexible arms for locomo ...

s. There are often many freckled catsharks (''Scyliorhinus haeckelii'') in the same habitat.

Biology

The lizard catshark lays a pair of eggs which are encased in greyish-green capsules with filamentous exteriors. The developing embryos feed on the egg yolks and hatch as miniature fish.

Status

The lizard catshark has been assessed by the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

as being a "

vulnerable species A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, ...

". This is because it has a small total population and a limited range, only of coastline, and lays its eggs in patches of coral which are susceptible to damage through

trawling Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net used for trawling is called a trawl. This principle requires netting bags which are towed through water to catch different speci ...

. The water temperature is low () in these parts and the coral is slow to regrow. The

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

advocates the cessation of trawling on the lower continental shelf and upper slope of the reefs to prevent further decline in this species.

References

{{Taxonbar, from=Q1951893 Schroederichthys Endemic fauna of Brazil Fish of Brazil Southeastern South American coastal fauna Vulnerable fish Vulnerable biota of South America Fish described in 2001