The pike topminnow (''Belonesox belizanus''), more commonly known as pike killifish and sometimes referred to as topminnow, is a species of

poeciliid The Poeciliidae are a family of freshwater fishes of the order Cyprinodontiformes, the tooth-carps, and include well-known live-bearing aquarium fish, such as the guppy, molly, platy, and swordtail. The original distribution of the family was t ...

found from

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

Nicaragua Nicaragua (; ), officially the Republic of Nicaragua (), is the largest country in Central America, bordered by Honduras to the north, the Caribbean to the east, Costa Rica to the south, and the Pacific Ocean to the west. Managua is the cou ...

. It has also been introduced to

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

, USA. It is the only known member of its

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

. The pike topminnow was described in 1860 by

Austrian Austrian may refer to: * Austrians, someone from Austria or of Austrian descent ** Someone who is considered an Austrian citizen, see Austrian nationality law * Austrian German dialect * Something associated with the country Austria, for example: ...

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

Rudolf Kner Rudolf Ignaz Kner (24 August 1810 – 27 October 1869) was an Austrian geologist, paleontologist, zoologist and ichthyologist. He also wrote some poems which were published by his brother-in-law K.A. Kaltenbrunner. Biography Kner was bo ...

, who gave the type locality as Belize, which is reflected in this species'

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 ...

Ecology

Unlike most poeciliids (which tend to be generalists or micropredators), this is a highly specialized predator, with an extremely flexible upper jaw that enables it to take very large prey items for its size.

Description

It grows typically to

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 ...

, exceptionally to . It has an elongated appearance with a flat back profile. The lower jaw is longer than the upper, and upturned. The pike topminnow has large eyes and a dorsal fin set far back on the body. It is a light, olive/brown color with light green iridescence and small black spots on the flanks. The belly is a lighter yellowish white. A dark spot is at the base of the

caudal 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 ...

. They are also a livebearing fish.

In the aquarium

This fish can be found in the

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

trade, but is not an easy aquarium resident, especially by poeciliid standards.

References

{{Taxonbar, from=Q1535154 Poeciliidae Freshwater fish of Mexico Freshwater fish of Central America Taxa named by Rudolf Kner Fish described in 1860 Live-bearing fish