''Valenciennellus tripunctulatus'', commonly called the constellationfish, 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

Sternoptychidae The marine hatchetfishes or deep-sea hatchetfishes as well as the related bottlelights, pearlsides and constellationfishes are small deep-sea ray-finned fish of the stomiiform family Sternoptychidae. They are not closely related to and should not ...

(hatchetfish).

Description

''Valenciennellus tripunctulatus'' is small, growing no longer than . It darkens its body at night by

pigment A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compo ...

dispersion. It is silvery-white in colour with several black spots; the name ''tripunctulatus'' ("three-spotted") refers to the larger spots on their ventral surface, although there are often more than three of these.

Habitat

''Valenciennellus tripunctulatus'' lives all the world's non-polar oceans. It 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 ...

and non-migratory, living at depths of .

Behaviour

''Valenciennellus tripunctulatus'' is a selective daytime feeder on

copepod Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor) ...

s (mainly '' Pleuromamma'') and

ostracod Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typic ...

s (such as '' Conchoecia''). It breeds year-round, with egg batches about 100–360 eggs per

ovary The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. ...

pair, the number increasing with animal size. It does not guard its eggs.

References

{{Taxonbar, from1=Q1038937 Sternoptychidae Fish described in 1871 Taxa named by Laurits Martin Esmark