Unresolved taxonomy confounds invasive species identification: the<i>Lysmata vittata</i>Stimpson, 1860 (Decapoda: Caridea: Lysmatidae) species complex and recent introduction of<i>Lysmata vittata</i>sensu stricto in the western Atlantic

Abstract Peppermint shrimp resembling Lysmata vittataStimpson, 1860, a species native to the Indo-West Pacific, were found in lower Chesapeake Bay and adjacent coastal embayments 2013, representing first recorded introduction of this northwestern Atlantic. Conflicting morphological descriptions, inconsistent terminology, limited molecular data (i.e., unresolved taxonomy), as well destruction type material L. vittata, created uncertainty regarding proper identification. We provide phylogeny incorporating individuals from across presumed introduced range vittata. Morphological phylogenetic analyses clearly indicate vittata represents complex two widely divergent groups: 1) “Bruce Type” with uniramous dorsal antennule that agrees A.J. Bruce’s 1990 redescription 2) “Rauli one-article accessory branch on most closely junior synonym rauliLaubenheimer &amp; Rhyne, 2010. Given taxonomic ambiguity surrounding we designate individual used by Bruce redescribe incorporated our neotype fix identity species. therefore identify North American New Zealand populations sensu stricto postulate spans temperate/subtropical East Asia. These suggest rauli is valid species, which includes possible undescribed sister confirm presence californicaStimpson, 1866 Zealand, non-native record for also suggesting disparHayashi, 2007 may be more widespread Pacific than currently known consider lipkeiOkuno Fiedler, 2010 likely synonym.