''Polymetme thaeocoryla'' 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

Phosichthyidae Lightfishes are small stomiiform fishes in the family Phosichthyidae The earliest fossils of lightfishes are from Oligocene-aged Paratethyan marine strata in the Czech Republic. They are very small fishes found in oceans throughout the world: ...

(lightfish). Its specific name is an anagram of the similar species, ''

Polymetme corythaeola The rendezvous fish (''Polymetme corythaeola'') is a species of fish in the family Phosichthyidae (lightfish). Its specific name is derived from the Greek κόρυθος (''korythos'', "helmet"); and αἰόλος (''aiolos'', "glittering"). D ...

''. It has no common name in English, but in Spanish is called ''luciérnaga musculosa'' ("muscular lightfish") and in French ''luisant grand feu'' ("gleaming ish ofgreat fire").

Description

''Polymetme thaeocoryla'' has a dark dorsum, with silver flanks and a black pigment on the outer caudal rays. Its length is maximum . It has 12 or 13 dorsal

soft rays Fish anatomy is the study of the form or morphology of fish. It can be contrasted with fish physiology, which is the study of how the component parts of fish function together in the living fish. In practice, fish anatomy and fish physiology co ...

, 30–34 anal soft rays, 44 or 45

vertebrae 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 i ...

, 7 or 8

pyloric caeca Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish a ...

and 17–19

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, ...

above 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 ...

Habitat

''Polymetme thaeocoryla'' is

benthopelagic 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 of ...

, living in the

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 .

Behaviour

Nothing is known of its early life stages.

References

Platytroctidae Fish described in 1990 Taxa named by Nikolai Vasilyevich Parin Taxa named by Oksana Dmitrievna Borodulina {{Rayfinned-fish-stub