Rediscovery and Redescription of the Leon Springs Pupfish, Cyprinodon bovinus, from Pecos County, Texas

Abstract

The Springs pupfish, Cyprinodon bovinus Baird and Girard, has been rediscovered after being considered extinct for more than 30 years. The present population is restricted to an 8-10 km segment of Creek and contiguous springs about 15 km downstream from, and in the same drainage as, the type locality for the species. The species is redescribed and its populational status and relationships to other species of Cyprinodon are discussed. Cyprinodon bovinus Baird and Girard (1853) was described from 16 specimens (Girard, 1859) collected in 1851, by the U. S. and Mexi- can Boundary Survey from Leon's Springs, Rio Grande del Norte. Subsequent attempts to collect the species were unsuccessful, and it was believed to be extinct (Hubbs, 1957; Miller, 1961). Then in December 1965 W. L. Minckley and W. E. Barber collected a pupfish thought possibly to be C. bovinus from a spring north of Fort Stockton, Pecos Co., Texas. This spring was referred to as Willbank Spring(s) by Minckley and Arnold (1969) and by Cole and Bousfield (1970), but, according to the Texas Water Development Board, the proper name is Diamond Y Recently, one of us (Echelle) obtained a large series from the same general locality, in Creek about 15 km downstream from, and in the same drainage as, the Springs which we regard to be the type locality of C. bovinus. The exact posi- tion of the type locality is not clear from the General Map given in the report of the U. S. and Mexican Boundary Survey (Emory, 1857), which shows two separate springs labeled Leon Spring. The nor- thernmost of these is probably the present Springs, since the