First Substantiated Report of Metacercaria of Crepidostomum cornutum (Trematoda, Digenea, Allocreadiidae) in Red Swamp Crayfish Procambarus clarkii from Southeast Texas, USA

Red swamp crayfish fi sh Procambarus clarkii were collected from Cattail Marsh in Beaumont, Texas and necropsied. Eight (13%) % ) of 62 crayfish fi sh collected were infected with metacercariae of Crepidostomum cornutum. Excysted metacercariae were stained and mounted for morphologic identification fi cation or preserved for molecular analysis. Morphometric values were consistent with those reported previously in the literature. Sequences of the 28S ribosomal RNA gene were aligned with the National Center for Biotechnology Information GenBank database. Blast analysis returned a result of 99% % similarity for C. cornutum. This study provides the fi rst report of C. cornutum metacercariae infecting P. clarkii in Texas substantiated by a voucher specimen and sequence data. Molecular data from this study should prove helpful in identification fi cation of adult stages from fi sh and cercariae from bivalves in future studies.