Jack Dempsey (fish)

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Jack Dempsey

Secure

Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Cichlidae
Genus:	Cichlasoma
Species:	C. octofasciatum

Binomial name

Cichlasoma octofasciatum
(Regan, 1903)

For other uses see Jack Dempsey (disambiguation).

The Jack Dempsey (Archocentrus octofasciatus (Regan, 1903), formerly Nandopsis octofasciatum and Cichlasoma octofasciatum) is a cichlid fish that is widely distributed across North and Central America (from Mexico south to Honduras).^[1]^[2] Its common name refers to its aggressive nature, likened to that of the famous 1920s boxer Jack Dempsey.^{[citation needed]}

1 Distribution
2 Ecology
3 Reproduction
4 Morphology
5 In the aquarium
6 Trivia
7 See also
8 References

[edit] Distribution

The fish is native to Yucatan and Central America, where it is found in slow-moving waters, such as swampy areas with warm, murky water, weedy, mud- and sand-bottomed canals, drainage ditches, and rivers.^[1] It is also established as an introduced species in Australia, the USA and Thailand (presumably as an aquarium escapee).^[3]

[edit] Ecology

The Jack Dempsey natively lives in a tropical climate and prefers water with a pH of 7-8, a water hardness of 9–20 dGH, and a temperature range of 22–30 °C (72–86 °F). It can reach up to 25 cm (10 in) in length. It is carnivorous, eating worms, crustaceans, insects and other fish. It can eat platies when it is three inches long. ^[1]

[edit] Reproduction

Jack Dempseys lay their eggs on the substrate (the bottom of the aquarium or pool). Like most cichlids, they show substantial parental care: both parents help incubate the eggs and guard the fry when they hatch. Jack Dempseys are known to be attentive parents, pre-chewing food to feed to their offspring. A lot of times however they will eat their fry when the breeding pair are overly disturbed or something in their environment is wrong.

[edit] Morphology

The coloration changes as the fish matures from a light gray or tan with faint turquoise flecks to a dark purple-gray with very bright, iridescent blue, green, and gold flecks. Their colors change under stress. The dorsal and anal fins of mature males have long, pointed tips. Females lack these exaggerated tips.

[edit] In the aquarium

Like most cichlids it is territorial, especially against its own kind and similar species. The fish was once very popular due to its striking appearance and personable mannerisms. It is a popular aquarium fish.

[edit] Trivia

In 1997 the San Francisco Chronicle reported that a man had died when he put a Jack Dempsey into his mouth as a joke: the fish presumably erected its fin spines to avoid being swallowed, a characteristic cichlid anti-predator response, and became wedged in the man's throat.^[4]

In a second season episode of Homicide: Life on the Street, a Jack Dempsey is recovered at the scene of a murder, and is taken home by an unsuspecting Detective John Munch, who intends to give it to his tropical fish-collecting girlfriend as a present. As a surprise, he places the fish in her aquarium, where it proceeds to devour $4,000 worth of her fish before being removed. Munch later refers to the fish as an "assassin" who "uses piranhas as toothpicks."