''Pachycara crassiceps'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

belonging to the

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 ...

Zoarcidae The eelpouts are the ray-finned fish family (biology), family Zoarcidae. As the common name suggests, they are somewhat eel-like in appearance. All of the roughly 300 species are ocean, marine and mostly bottom-dwelling, some at great depths. Eel ...

, the

eelpout The eelpouts are the ray-finned fish family Zoarcidae. As the common name suggests, they are somewhat eel-like in appearance. All of the roughly 300 species are marine and mostly bottom-dwelling, some at great depths. Eelpouts are predominantly ...

s. It is found in the Eastern Atlantic Ocean.

Taxonomy

''Pachycara crassiceps'' was first formally described as ''Lycenchelys crassiceps'' by the French

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...

Louis Roule Louis Roule (; 20 December 1861 – 30 July 1942) was a French zoologist born in Marseille. In 1881 he obtained a degree in natural sciences at Marseille, followed by his doctorate of sciences (1884) at Paris with a thesis on ascidians of coastal ...

with its type locality given as the Gulf of Gascony. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''crassiceps'' means "thick headed" and allusion to the head being larger than the head of '' Lycenchelys paxillus'', with which it was presumed to be congeneric.

Description

''Pachycara crassiceps'' has a moderately elongate body which has a depth at the origin of the

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

equivalent to between 11% and 14 % of its

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

, or 11.7% to 13.6 % of its

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

. The scales cover up to the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s, nape and on the bases of all of the fins. It has a small head with its palatine teeth do not point backwards and are set in a double row at the front of the bone at a minimum. The

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

s have between 17 and 19 fin rays while it does have

s. The body before the anus is around two fifths of the standard length. There is a double

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

, one ventral and the other along thje middle of the flanks. This species is uniformly black or dark chocolate brown in colour with a blue eyea nd a bluish tinge on the belly in juveniles, black in adults. This species attains a maximum

of .

Distribution and habitat

''Pachycara crassiceps'' is found in the eastern Atlantic Ocean where it has been recorded off southwest Ireland, in the

Bay of Biscay The Bay of Biscay (), known in Spain as the Gulf of Biscay ( es, Golfo de Vizcaya, eu, Bizkaiko Golkoa), and in France and some border regions as the Gulf of Gascony (french: Golfe de Gascogne, oc, Golf de Gasconha, br, Pleg-mor Gwaskogn), ...

, the

Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...

and off Mauritania and Senegal. This is a benthic specieswhich lives on muddy substrates at depths ranging between .

Behaviour

''Pachycara crassiceps'' eats

sipunculid worms The Sipuncula or Sipunculida (common names sipunculid worms or peanut worms) is a class containing about 162 species of unsegmented marine annelid worms. The name ''Sipuncula'' is from the genus name ''Sipunculus'', and comes from the Latin '' ...

and

polychaetes Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are mad ...

. It is

parasitised Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

by ''Echinorhynchus brayi'' worms.

References

{{Taxonbar, from=Q1114327 crassiceps Fish described in 1916 Taxa named by Louis Roule