Identifying lineages of Alpheus angulosus McClure, 2002 (Caridea: Alpheidae) in South Carolina, USA.

The Alpheus armillatus H. Milne Edwards, 1837 species complex contains several cryptic species of snapping shrimps including Alpheus angulosus McClure, 2002. A previous study of the phylogeography and coloration of the A. armillatus species complex found three distinct lineages of A. angulosus distributed throughout the Gulf of Mexico, Caribbean, and Western Atlantic, with the Atlantic coastline of North America less thoroughly studied. We sequenced a portion of the mitochondrial cytochrome oxidase I gene of 20 individuals of A. angulosus from Charleston, South Carolina, USA to determine the lineages present. We found two of the three lineages of A. angulosus; nineteen specimens were found to be within a subtropical clade, whereas one was within a clade previously described as having only a Caribbean distribution. We found that body coloration was not consistent with biogeographical patterns observed in previous studies, which suggests that coloration should only be used in conjunction with genetics and other morphological characters when determining identities of cryptic species. [ABSTRACT FROM AUTHOR]