A review of the new world species of the shore-fly genus Leptopsilopa Cresson (Diptera: Ephydridae)

The 12 New World species of Leptopsilopa are reviewed, including the following new species (type localities noted parenthetically): L. andiana (Peru. Huanuco: Espensa, [ 11 km N Hudinico]), L. flavicoxa (Belize. Stann Creek: Cockscomb Basin Wildlife Sanctuary [16 degrees 47'N, 88 degrees 30'W]), L. martharum (United States. Texas. Jim Wells: Mathis (7.5 km S; Nueces River; 28 degrees 02.2'N, 97 degrees 52.2'W; 15 m), and L. placentia (Belize. Stann Creek-Placentia Lagoon, Rum Point; 16 degrees 32'N, 88 degrees 21'W). Lectotypes are designated for Psilopa similis Coquillett, Psilopa varipes Coquillett, and Psilopa metallina Becker. The monophyly of Leptopsilopa is established, but only if the Old World species are excluded. The genus is most closely related to a lineage of species currently included in the genus Psilopa (the dupla group, including R metallina), which is rendered paraphyletic by the recognition of Leptopsilopa as an included, monophyletic lineage. The New World species are arranged into two monophyletic species groups, the atrimana and the similis groups. Of the 12 species now recognized, 10 occur in the neotropics, where other undescribed species will probably be discovered.