Potentially Endangered Cicurina Spiders from the San Antonio Area

Cicurina spider
Cicurina spider. Photo by Dr. Jean K. Krejca, Zara Environmental LLC.
Funding from the Texas Department of Transportation (TxDOT) allowed staff of the NSRL and TTU’s Department of Biological Sciences to investigate the genetics and morphology of Cicurina cave spiders from Bexar and surrounding counties of Texas.  Those involved in the study included:  Robert J. Baker, former Horn Professor of Biological Sciences and former Director of the NSRL; James C. Cokendolpher, Assistant Curator of Invertebrate Zoology, NSRL; Julie A. Parlos, former Ph.D. student in Biological Sciences; Caleb D. Phillips, Assistant Professor of Biology and Curator of the Genetic Resources Collection, NSRL, as well as Stirling Robertson of TxDOT and Jean Krejca of Zara Environmental, LLC.

Bexar County is home to a diverse fauna of endemic species found in the karstic areas in and around the Edwards Aquifer region and associated springs.  The fauna of Bexar County are experiencing increased anthropogenic pressures resulting from suburban development and human expansion.  Among this fauna are troglobitic species of the genus Cicurina, several of which are already listed as endangered by the U.S. Fish and Wildlife Service.  Adult specimens rarely are observed, with most species only being recognized by differences in sexual reproductive anatomy of one or a few specimens. Immature specimens

spider genitalia
Genitalia of a female Cicurina spider
are more commonly observed, but still require extensive field work to observe or collect.  By using morphologically identified adult specimens and genetics of immature specimens, distributions of phylogenetic clades across the karst faunal regions of Bexar County were characterized.  The development of this paired morphologic and genetic database will serve to improve the identification of species from immature specimens, which are most commonly obtained during suburban excavation projects.

Two manuscripts are in preparation on 1) the genetic boundaries of the species, and 2) macroscopic (combined focus-stacked) photography of the reproductive organs that are used in the taxonomy of this group of spiders.