Systematics and updated range alter the conservation status of the Louisiana Needlefly, Leuctra szczytkoi Stark & Stewart, 1981 (Plecoptera: Leuctridae)

The Louisiana Needlefly, Leuctra szczytkoi Stark & Stewart, 1981, was one of 404 species petitioned in 2010 by the Center for Biological Diversity for inclusion and protection under the United States Endangered Species Act. There were only four known locality records in northern and central Louisiana before the start of this project, all collected between 1973 and 1997. Prior published research, however, provided tangible evidence that L. paleo Poulton & Stewart, 1991 could be a junior synonym of L. szczytkoi. The type localities of these two species (L. paleo—southern Arkansas; L. szczytkoi—northern Louisiana) are only separated by approximately 120 km. The primary objective of this study was to use mitochondrial cytochrome C oxidase subunit 1 gene sequences to assess the taxonomic validity of L. paleo using tree- and genetic distance-based phylogenetic analyses. Results of all analyses provide consistent and strong evidence that L. paleo is a junior synonym of L. szczytkoi. Hence, L. szczytkoi has nomenclatural priority with an expanded known distribution now from southern Arkansas southward to central Louisiana and southwestward to east Texas with 20 unique locations. Additional notes on other members of the L. ferruginea (Walker, 1852) group are provided.