This species was once one of the most abundant fishes in the Pecos River, but is now restricted to Salt Creek in Texas and just a few locations in New Mexico due to hybridization with Sheepshead Minnow (C. variegatus) and groundwater pumping. As a result, it is classified as Threatened in Texas. It has a wide tolerance for physiochemical factors such as temperature, salinity, and oxygen. For example, individuals can move from water more salty than sea water into totally fresh water, with no ill effects. It can also vary reproductive traits such as age at maturity, ovary size, and egg number in response to changing environments.
To learn more visit: http://www.fishesoftexas.org/taxa/Cyprinodon-pecosensis
Content author: Dr. Gary Garrett
Illustration: Joseph R. Tomelleri
