Critically Endangered
Butterfly splitfin
Ameca splendens
The butterfly splitfin or butterfly goodeid is a bony fish from the monotypic genus Ameca of the splitfin family (Goodeidae).
Appearance
In a dominant mature male specimen the large dorsal fin is like the caudal fin washed with black. A yellow band stretches along the caudal's back margin. The body of both sexes is ochre, with silvery sides and a brownish back, that in males usually have numerous glittering metallic scales.
As usual in live-bearers, males are the smaller sex, reaching some 3 in (7–8 cm) total length at best, with females being able to grow up to 4 in (10 cm) under good conditions.
Range and habitat
It was formerly found throughout the Ameca River drainage in Mexico. The type locality is Rio Teuchitlán in the vicinity of Teuchitlán, Jalisco, near the town of Ameca. The species was historically only found in an area about 10 miles (15 km) in diameter but in the early 21st century, searches have found it in a few other locations in the region, up to 100 km away at Cuyacapán. A remnant population was found to persist in El Rincón waterpark, where the Rio Teuchitlán's springs have been dammed for bathing, between Teuchitlán town and he prehistoric site of Guachimontones, but it is unclear if this population still survives.
Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.
Breeding
Like other Goodeidae, butterfly splitfins mate by internal fertilization and spawn fully developed young.
In crisis
Today, the species is rated as critically endangered by the IUCN. Possibly, it also exists in a feral state in the United States. Individuals apparently derived from escaped or introduced captive stock were found in Rogers Warm Spring in southeastern Nevada, but this was in the early 1980s, and the species' persistence there is unclear. For some time, it was a popular fish among aquarists, but hobbyist stocks have declined more recently, placing its survival in jeopardy.
Butterfly splitfin is Critically Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.
Sources
Written for this catalog from the English Wikipedia article on Butterfly splitfin, Wikidata item Q460553. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.
