Fish species native to Mexico discovered on U.S. side of border

Image: Texas A&M AgriLife

Two scientists and their team from Texas A&M University have made an extremely rare find in the Rio Grande River along the Texas border with Mexico.

They discovered the Conchos shiner, Cyprinella panarcys, a species of fish identified for the first time on record in the United States during April in the mainstream of the Rio Grande at the confluence with Alamito Creek in Presidio County.

The discovery belongs to Kevin Conway, an associate professor and curator of fishes for Biodiversity Research and Teaching Collections, and Joshuah Perkin, an assistant professor, both in the Department of Wildlife and Fisheries Sciences.

“We found this fish by chance,” said Perkin. “We were conducting a survey for a declining species known as the Rio Grande shiner, Notropis jemezanus, but found none of that species. In fact, it’s quite remarkable that we could find a species never before detected in the U.S. but could not find a single Rio Grande shiner.”

Previously, the Conchos shiner was considered restricted to the upper parts of the Río Conchos drainage in Mexico, extending from the Río San Pedro at Meoqui in Chihuahua to the Río Florido in Durango.

It is unique to see the species in other waters. According to Conway, there are two alternatives that could explain the unexpected discovery of the Conchos shiner in Texas: “Either this species is native to Texas, but its presence has simply gone unnoticed until now, or we were exceptionally lucky and managed to capture a rare vagrant outside of its natural distribution.”