Local Distribution and Conservation Implications for Recovery of Troglobitic Species of Endangered Mold Beetle in Williamson County, Texas

Current distribution records for Batrisodes texanus Chandler have become more refined since the species was federally listed as endangered in the United States almost 30 years ago. Distribution and range records are compiled from a variety of sources, including dedicated surveys of karst biota in various preserves in Williamson County, Texas, and karst feature investigations triggered by development requirements established for compliance with the Endangered Species Act. The species range is determined by factors not considered in current delineations generated in 1992 of karst fauna regions that serve as a model for de facto recovery units used by the U.S. Fish and Wildlife Service. Current recovery unit delineations might inhibit official downlisting of species despite significant existing and planned conservation efforts. This untenable situation probably is the direct result of improper boundary placement between recovery units; the authors recommend modifying a single recovery unit boundary to better reflect the distribution of the species as determined by in situ field surveys. The authors recommend modifying the recovery unit system to include the entire range of the species within a single recovery unit.