Macroarthropod communities of Sandy Springs of East Texas

Abstract

The macroarthropod fauna of first- and second-order sandy streams of the Carrizo-Wilcox aquifer system was sampled and compared with the fauna of temporary and standing spring-fed habitats in the same area, as well as with the fauna of limestone streams on the western border of this sand deposit. The taxa collected are discussed with new species and distribution records. Indicator and expected species in permanent, sandy, first-order streams of the Carrizo-Wilcox aquifer are shown to be Synurella near bifurca, Crangonyx pseudogracilis, Calopteryx maculata, Argia immunda, Cordulegaster maculata, Diplectrona modesta, Molanna tryphena, and Bittacomorpha clavipes. Comparisons with the spring fauna of the Edwards Plateau show that east Texas springs have low endemicity and are dominated by Nearctic taxa which are restricted to colder stream headwaters where springs of the Edwards aquifer have high endemicity and are dominated by western and tropical groups.