Eucalantica: a lost child of Saridoscelinae, a subfamily new to the New World

Eucalantica is a monotypic genus described by Busck (1904) to accommodate Calantica polita Walsingham, 1881 from the western parts of North America. It is superficially similar to Niphonympha Meyrick, 1914, a replacement name of Calantica Zeller, 1847, but differs from the latter by labial palpus and wing venation (Busck, 1904). The systematic position of Eucalantica is the subject of continued controversy. Fletcher (1929) and Heppner & Duckworth (1983) placed it in Plutellidae, while Kyrki (1990) placed it in Yponomeutidae. This disagreement, we discover, stems from a lack of critical morphological comparison of Eucalantica to other supposedly related genera. Our detailed examination of Eucalantica shows it to possess several probable synapomorphies with the East Asian genus Saridoscelis, the type genus of the monotypic subfamily Saridoscelinae (Yponomeutidae). The features involved include the shape of labial palpus and hindwing venation (three-branched M veins), male sternum VIII, and the socii-gnathos-tegumen complex. Eucalantica and Saridoscelis also share an association with Vaccinium (Ericaceae), although larval food plants are known for few species. Our hypothesis that Eucalantica belongs to Saridoscelinae is tested by molecular data. Three new species of Eucalantica from Mexico and Costa Rica are described, giving new insights on the biogeography of the genus.