The multipore searsid (''Normichthys operosus'') 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 fish in the family

Platytroctidae The tubeshoulders are a family, Platytroctidae, of ray-finned fish belonging to the order Alepocephaliformes Alepocephaliformes is an order of ray-finned fish. It was previously classified as the suborder Alepocephaloidei of the order Argenti ...

(tubeshoulders).

Name

Its scientific name is from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''operōsus'', "busy, hardworking". Its common name "multipore" refers to the dermal pits located behind its shoulders, and " searsid" is a name used for fish that resemble ''

Searsia koefoedi ''Searsia koefoedi'', or Koefoed's searsid, is a species of tubeshoulder found in the oceans at depths of from . It is named after Norwegian marine biologist Einar Koefoed Einar Laurentius Koefoed (1875–1963) was a Danish-born marine biolog ...

''.

Description

The multipore searsid is maximum long and is black or dark brown in colour. Its body is deep and compressed, its head about one-third of body length. It has a simple

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 ...

and few or no

photophores A photophore is a glandular organ that appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors, ...

. It has two to four large, and several smaller, open dermal pits behind the upper part of

shoulder girdle The shoulder girdle or pectoral girdle is the set of bones in the appendicular skeleton which connects to the arm on each side. In humans it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists of t ...

, with usually at least one pit twice as wide as body scales; these give it the name "multipore."

Habitat

The multipore searsid is

bathypelagic The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The bathypelagic ...

, living in

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

at depths of , but rarely going below , following a isotherm and being found near

seamount A seamount is a large geologic landform that rises from the ocean floor that does not reach to the water's surface (sea level), and thus is not an island, islet or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abru ...

s. It is most concentrated in the waters southwest of

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

References

Platytroctidae Fish described in 1951 Taxa named by Albert Eide Parr {{Rayfinned-fish-stub