View source for Flagfish

{{Short description|Species of fish}}
{{Use American English|date=January 2024}}{{Use mdy dates|date=January 2024}} 
{{Speciesbox
| name = Flagfish
| image = Jordanella floridae.jpg
| taxon = Jordanella floridae
| status = G5
| status_system = TNC
| status_ref = <ref name=NatureServe>{{cite web |title=''Jordanella floridae'' |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.105947/Jordanella_floridae |website=NatureServe Explorer An online encyclopedia of life |version=7.1|publisher=NatureServe|accessdate=28 November 2022}}</ref>
| parent_authority = [[George Brown Goode|Goode]] & [[Tarleton Hoffman Bean|T. H. Bean]], 1879
| authority = Goode & T. H. Bean, 1879
| synonyms = ''Cyprinodon floridae'' <small>(Goode & T.H. Bean, 1879)</small>
| synonyms_ref = <ref name = Fishbase>{{Fishbase|Jordanella|floridae|month=August|year=2019}}</ref>
}}

The '''flagfish''' ('''''Jordanella floridae'''''), also known as the  '''American flagfish''' or '''Florida flagfish''', is a species of [[pupfish]], a type of [[killifish]] from the [[Family (biology)|family]] [[Cyprinodontidae]] which is [[endemic]] to [[Florida]].<ref name=NatureServe/> It is found in the [[Fish keeping|aquarium]] trade. Its common name derives from the dominant males' body pattern, which bears some resemblance to the [[Flag of the United States]].

==Description==
[[File:Flagfish.webm|thumb|A Male in an aquarium.]]
Flagfish are small, robust fish, {{convert|6|cm|in}} in length, with a truncated snout which has been compared to that of a [[bulldog]]. They have rounded fins with the [[dorsal fin|dorsal]] and [[anal fin]]s positioned posteriorly and adjoining the [[caudal fin]]. Females have an obvious spot on their flanks and a clear spot near the posterior end of the dorsal fin, this has an opaque white margin. The fins may show a slight reddish color but this comes and goes in any individual but the reason for this is unknown. The females body is mainly olive but marked with turquoise scales. The common name of the flagfish is derived from the male due to the resemblance of its patterning to the [[flag of the United States]]. There is a dark rectangle on the shoulder which is imagined as the blue and white stars in the corner of the US flag and there are stripes along the flanks, some of which are red and others paler, albeit greenish rather than white. The male also has a dark spot positioned at the lower posterior corner of the dark rectangle. The olive-grey coloration and pattern of nondominant males, females, and juveniles underlies the more colorful pattern of the dominant males.<ref name = Sweeney>{{cite web | url = http://en.microcosmaquariumexplorer.com/wiki/Secrets_of_the_American_Flagfish | title= Secrest of the American Flagfish | author = Mary E. Sweeney | accessdate=19 October 2019 | website = Microcosm Aquarium Explorer}}</ref>

==Distribution==
The flagfish is endemic to Florida where it is found in the [[Florida Peninsula]] south of the [[drainage basin]]s of the [[St. Johns River]] and [[Ochlockonee River]].<ref name = Fishbase/>

==Habitat and biology==
The flagfish normally occurs in shallow, well vegetated freshwater habitats such as backwaters, marshes, canals and ditches but it has occasionally been recorded in slightly brackish water.<ref name = SF>{{cite web | url = https://www.seriouslyfish.com/species/jordanella-floridae/ | title = ''Jordanella floridae'' GOODE & BEAN, 1879 Florida Flagfish | accessdate = 19 October 2019 | website = Seriously Fish}}</ref> The flagfish is listed in the [[Guinness Book of World Records]] as the species of fish which lays the fewest eggs, a female will lay 20 eggs over a period of a few days.<ref name = Fishbase/> They have a courtship display in which the female encourages the male to chase her by nipping him. After that they face each other with the female swimming backwards, the male then backflips. After the eggs are laid the male guards them, attacking fish which stray too close. However, the male may also eat his own eggs or offspring.<ref name = Sweeney/> Other sources say that this species shows no parental care.<ref name = SF/>

This species is omnivorous, it is a micropredator feeding on small invertebrates and zooplankton but it will also feed on algae and other plant material.<ref name = SF/>

They are often used to naturally control hair algae in suitable aquariums, as they are one of the only fish to consume it in an impactful volume.<ref>{{Cite web|url=https://aquariumtidings.com/american-flagfish-care-feeding-breeding-american-flagfish/|title = American Flagfish - the Care, Feeding and Breeding of American Flagfish|date = 6 January 2015}}</ref>

==Taxonomy and name==
The flagfish was [[Species description|described]] by George Brown Goode and Tarleton Hoffman Bean in 1879 with the [[Type locality (biology)|type locality]] given as [[Lake Monroe, Florida]].<ref name = CofF>{{Cof record|spid=13988|title=Jordanella floridae|access-date=19 October 2019}}</ref> The generic name honours the [[United States|American]] [[ichthyologist]] [[David Starr Jordan]] (1851–1931).<ref name = ETYFish>{{cite web | url = http://www.etyfish.org/cyprinodontiformes3/ | work = The ETYFish Project Fish Name Etymology Database | author1 = Christopher Scharpf | author2 = Kenneth J. Lazara | date = 26 April 2019 | title= Order CYPRINODONTIFORMES: Families PANTANODONTIDAE, CYPRINODONTIDAE, PROFUNDULIDAE, GOODEIDAE, FUNDULIDAE and FLUVIPHYLACIDAE | accessdate = 19 October 2019 | publisher = Christopher Scharpf and Kenneth J. Lazara}}</ref> It is closely related to the [[Yucatan flagfish]] ''Garmanella pulchra'' which is sometimes also placed in the genus ''Jordanella''.<ref name = SF/>

==References==
{{reflist}}

==External links==
* [http://brackishfaq.blogspot.com/2016/08/killifish-note-many-thanks-are-also-due.html Florida flagfish entry on Brackish FAQ]
* [http://www.wetwebmedia.com/FWSubWebIndex/cyprinodonts.htm Florida flagfish at Wet Web Media]

{{Taxonbar|from=Q861774}}

[[Category:Cyprinodontidae]]
[[Category:Fauna of the Southeastern United States]]
[[Category:Freshwater fish of the Southeastern United States]]
[[Category:Fish described in 1879]]
[[Category:Taxa named by George Brown Goode]]
[[Category:Taxa named by Tarleton Hoffman Bean]]
[[Category:Endemic fauna of Florida]]
[[Category:Endemic fish of the United States]]
[[Category:Taxobox binomials not recognized by IUCN]] <!-- Jordanella floridae -->