Tecopa Pupfish (Cyprinodon nevadensis ssp. calidae)
The Tecopa Pupfish was described in 1948, it was restricted to some outlets of the North- and South Tecopa Hot Springs in Inyo County, California, USA.
The two hot springs that this fish inhabited were very popular in the 1950s and 60s and were used for recreationally purposes; bathhouses were built, the spring pools were enlarged and their outflows were diverted which resulted in swifter currents which again caused the water temperatures downstream to rise above the level to which this pupfish was adapted.
All these modifications also allowed a subspecies closely related to this form, the Amargosa River Pupfish (Cyprinodon nevadensis ssp. armagosae Miller), to invade the Tecopa Pupfish’s habitat and to hybridize with it.
The last presumed Tecopa Pupfishs were recorded in 1966, but these, having ‘too small’ scales, may already have been hybrids.