Abstract: | The tribe Liparocephalini (genera Liparocephalus Mäklin, 1853;Diaulota Casey, 1893 [ = Genoplectes Sawada, 1955];Paramblopusa Ahn & Ashe, Amblopusa Casey, 1893;Salinamexus Moore & Legner, 1977 [ = Biophytosus Moore & Legner, 1977]), all of which are exclusively restricted to the Pacific coasts of the Holarctic Region, is hypothesized to be a monophyletic group based on the following synapomorphies: seta v absent (inferred to be lost) from mentum (reversed one time in the Liparocephalus lineage), setae distributed only on mesal surface of galea and apex with setae, one medial seta present on prementum, and contiguous mesocoxal cavities. Natural history and history of the classification of the Liparocephalini are discussed. Phylogenetic analyses of the species of the Liparocephalini are presented based on larval (21 characters, 57 states), adult (49 characters, 115 states), and a combination of larval and adult characters (70 characters, 172 states). Analysis of the combined larval and adult data sets with successive approximation resulted in a single most parsimonious tree (length = 937, CI = 0.885, RI = 0.930) with the following patterns of generic relationships (outgroup (Salinamexus + Biophytosus (Amblopusa (Paramblopusa (Diaulota + Genoplectes, Liparocephalus))))). |