Revisiting a long-standing taxonomic controversy: DNA evidence suggests revision of the <i>Limenitis arthemis</i> complex (Lepidoptera: Nymphalidae: Limenitidinae)

Changes in the taxonomic status of the phenotypically distinct North American butterflies known as “white admirals” and “red-spotted purples” are proposed. Originally described as separate species, L. arthemis (Drury, 1773) and L. astyanax (Fabricius, 1775), respectively, most workers now accept – sometimes with reservation – that they should be grouped into a single species, L. arthemis. Herein, the taxonomic history and geographic distribution of subspecies of the L. arthemis complex, and the controversy that occurred mainly during the 20th century, are briefly reviewed. Previously published molecular data employing both mitochondrial and nuclear markers – not available during the height of the controversy – together with new phylogenetic analysis of available mitochondrial DNA barcodes suggest allopatric speciation occurred in this complex and that the current taxonomy is in need of revision. It is proposed here to elevate L. arthemis astyanax to a full species, L. astyanax reinst. stat., and to revise the name of the Arizona red-spotted purple from L. arthemis arizonensis W.H. Edwards to L. astyanax arizonensis reinst. stat.