First Account of a Living Population of Texas Fawnsfoot, Truncilla macrodon (Bivalvia: Unionidae), in the Brazos River, Texas

Abstract

A recent survey of the lower Brazos River in Grimes and Washington counties, Texas, resulted in the first record of a living population of Truncilla macrodon since its description in 1859. Truncilla macrodon is endemic to the Brazos and Colorado basins of central Texas. Anthropogenic impacts resulted in a decline in abundance and distribution for this species prior to extensive scientific study. Given the absence of information on natural history for this species, we documented preliminary physical and biological characteristics associated with this population.