The narrowmouthed catshark (''Schroederichthys bivius'') is a

coloured catshark Atelomycteridae, the coloured catsharks, is a family of sharks belonging to the order Carcharhiniformes. These sharks are found in the Indian, Pacific and Western Atlantic Oceans. Genera Atelomycteridae contains the following genera and specie ...

beloning to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Atelomycteridae Atelomycteridae, the coloured catsharks, is a family of sharks belonging to the order Carcharhiniformes. These sharks are found in the Indian, Pacific and Western Atlantic Oceans. Genera Atelomycteridae contains the following genera and specie ...

, found from central

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

around the

Straits of Magellan The Strait of Magellan (), also called the Straits of Magellan, is a navigable sea route in southern Chile separating mainland South America to the north and the Tierra del Fuego archipelago to the south. Considered the most important natural ...

, to

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

between

latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...

s 23° S and 56° S, at depths down to about in the Atlantic Ocean and about in the Pacific. It can grow to a length of up to . The reproduction of this catshark is

oviparous Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (i.e., by laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings kno ...

Taxonomy

The narrowmouthed catshark was first formally described as ''Scyllium bivium'' in 1838 in the book ''Systematische Beschreibung der Plagiostomen'' written by

Johannes Peter Müller Johannes Peter Müller (14 July 1801 – 28 April 1858) was a German physiologist, comparative anatomist, ichthyologist, and herpetologist, known not only for his discoveries but also for his ability to synthesize knowledge. The paramesonephri ...

and

Friedrich Gustav Jakob Henle Friedrich Gustav Jakob Henle (; 9 July 1809 – 13 May 1885) was a German physician, pathologist, and anatomist. He is credited with the discovery of the loop of Henle in the kidney. His essay, "On Miasma and Contagia," was an early argument ...

in which they ascribe the name to the Scottish

surgeon In medicine, a surgeon is a medical doctor who performs surgery. Even though there are different traditions in different times and places, a modern surgeon is a licensed physician and received the same medical training as physicians before spec ...

and

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

Andrew Smith. Smith gave the type locality as the

Cape of Good Hope The Cape of Good Hope ( ) is a rocky headland on the Atlantic Ocean, Atlantic coast of the Cape Peninsula in South Africa. A List of common misconceptions#Geography, common misconception is that the Cape of Good Hope is the southern tip of Afri ...

when he published the name in the South African Quarterly Journal of October 1831. This species is classified within the genus ''

Schroederichthys ''Schroederichthys'' is a genus of coloured catsharks in the family Atelomycteridae Atelomycteridae, the coloured catsharks, is a family of sharks belonging to the order Carcharhiniformes. These sharks are found in the Indian, Pacific and We ...

'' which is currently included in the family Atelomycteridae, the coloured catsharks.

Description

As a juvenile, the narrowmouthed catshark is elongated and very slender, but as it grows its proportions change and it becomes rather more thickset. Its adult length can reach or more. The snout is rounded and slender and the front nasal flaps are narrow and lobed. This fish displays heterodont dentition; the mouth is long in both sexes, but is longer and narrower in males, with teeth that are twice the height of those of females. The general colour of the dorsal surface of both sexes is greyish-brown, with seven or eight dark brown saddles. Some large dark spots are scattered along the body but do not occur on the saddles. There are also many small white spots on the upper half of the body.

Distribution

The narrowmouthed catshark is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the coasts of South America, between

s 23° S and 56° S. In the southwestern Atlantic Ocean its range extends from southern Brazil, southwards to the

Beagle Channel Beagle Channel (; Yahgan language, Yahgan: ''Onašaga'') is a strait in the Tierra del Fuego, Tierra del Fuego Archipelago, on the extreme southern tip of South America between Chile and Argentina. The channel separates the larger main island of I ...

and in the southeasterly Pacific Ocean, southwards from northern Chile. Its depth range is from the surface down to about in the Atlantic Ocean and about in the Pacific.

Ecology

The narrowmouthed catshark is a

demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer o ...

fish, feeding mostly on crustaceans and some fish. In the Beagle Channel in the summer it has been found to feed almost exclusively on the

squat lobster Squat lobsters are dorsoventrally flattened crustaceans with long tails held curled beneath the cephalothorax. They are found in the two superfamilies Galatheoidea and Chirostyloidea, which form part of the decapod infraorder Anomura, alongs ...

'' Munida gregaria'', but in other places its diet is more varied. The females are oviparous, the eggs being laid in egg cases which are attached to the seabed in estuaries and sheltered waters by tendrils. The newly hatched juvenile fish use these sheltered areas as nurseries.

Status

The

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

has assessed this species as "least concern". *

References

{{DEFAULTSORT:catshark, narrowmouthed

narrowmouthed catshark The narrowmouthed catshark (''Schroederichthys bivius'') is a coloured catshark beloning to the family (biology), family Atelomycteridae, found from central Chile around the Straits of Magellan, to Argentina between latitudes 23rd parallel south, ...

Fish of Chile Fish of Argentina Fauna of Temperate South America Taxa named by Johannes Peter Müller Taxa named by Friedrich Gustav Jakob Henle