Golden skiffia

Río Ameca in western Mexico.^[3] It is extinct in the wild,^[1] but has been maintained in aquaria and the aquarium hobbyist trade.^[4]

Copeia by Dolores Kingston, from preserved and live specimens in the University of Michigan Museum of Zoology. This species was named in honor of Frances H. Miller who, along with her husband Robert Rush Miller, helped to collect and ship the live specimens.^[3]

standard length (SL) of around 4.3 cm (1.7 in), with a wedge shaped head and upturned lips. It has of a row 30–35 deeply cleft outer teeth in both the upper and lower jaws. Inner teeth can be cleft or conical, and are scattered irregularly. The species shows sexual dimorphism with males having larger fins, and a greater body and head depth. Males also have a notched dorsal fin, which females lack. Males are a bright gold color with a gray overcast. The gold coloration is most vibrant during courtship, largely fading to the dorsal, caudal, and anal fins in non-courting males. Females have a greater body width, and both females and juveniles are gray-green, with scattered black flecks on their backs and along the lateral line. Females do not change color during courtship. Both sexes have a black crescent just before the tail fin.^[3]

ovaries are merged into a single organ, in which the young are gestated. This organ is capable of enlarging as the young develop. While in the ovary, the young possess trophotaenia. Each trophotaenia has three lobes containing blood vessels, which are believed to function in nutrient and gas exchange. Newborn young lose their trophotaenia shortly after birth.^[3] The gestation period is 55–60 days, with a usual brood size of 10–15 young.^[5]

Xiphophorus maculatus was found. This introduced species was found to outnumber Golden skiffia by a factor of 50. Golden skiffia's numbers were dramatically reduced within a year, likely due to competition from X. maculatus.^[3]

benthic feeder, as indicated by gut contents dominated by pennate diatoms.^[3]

tequila splitfin into the Teuchitlán. To prepare the individual fish for their return, fish marked for release were first placed in ponds to adapt to semi-captive conditions. From there they were dewormed and marked, before being taken to mesocosms in the river itself to experience and adapt to natural conditions prior to release.^[7]