The New World genus Lepidosina Marshall & Buck gen. n. is described including nine new and two previously described species: L. angusticercus Marshall & Buck sp. n. (Caribbean, Central and South America), L. argentinensis Marshall & Buck sp. n. (Argentina), L. cubensis Marshall & Buck sp. n. (Cuba), L. evanescens Marshall & Buck sp. n. (Central and South America), L. gibba (Spuler) comb. n. (Florida, Caribbean), L. inaequalis (Malloch) comb. n. (southern U.S.A., Central America, Venezuela), L. multispinulosa Marshall & Buck sp. n. (Ecuador, Peru), L. platessa Marshall & Buck sp. n. (Bolivia), L. proxineura Marshall & Buck sp. n. (Brazil), L. quadrisquamosa Marshall & Buck sp. n. (Venezuela), and L. rutricauda Marshall & Buck sp. n. (Colombia to Peru). Keys to males and females are provided, and the species level phylogeny is analyzed based on a matrix of 24 morphological characters. The sister group of this well-defined, highly apomorphic genus remains unknown. Most species are restricted to lowland habitats. Larvae and puparia of Lepidosina remain unknown.
The New World species of Loxocera Meigen are revised including two new species, L. (Imantimyia) ignyodactyla Buck sp. n. from Costa Rica (first record of the genus from the Neotropical region) and L. (Imantimyia) ojibwayensis Buck sp. n. from Ontario, Canada. Loxocera californica Capelle is synonymized with L. collaris Loew and lectotypes are designated for L. pleuritica Loew and L. cylindrica var. obsoleta Johnson (both synonyms of L. cylindrica Say). The New World species are diagnosed and a key to species is provided. The male and female terminalia of Loxocera are described in detail for the first time, and their functional morphology is discussed. Eggs of most species are described and a key to the known eggs of Loxocera is provided. A phylogenetic framework for the Holarctic subgenera and species groups of Loxocera is developed based on morphological characters of the adult flies. The Old World subgenus Platystyla Macquart is synonymized with Loxocera s. str., and Imantimyia Frey is reinstated as a valid subgenus including all Holarctic species previously placed in Loxocera s. str. except the L. aristata species group. This leads to the following new subgeneric combinations: L. (L.) malaisei Frey comb. n., L. (L.) matsumurai Iwasa comb. n., L. (L.) monstrata Iwasa, comb. n., and L. (L.) omei Shatalkin comb. n. The species groups of Imantimyia are redefined, i.e. the L. achaeta-group (7 spp.), the L. fulviventris-group (4 spp.), and the L. albiseta-group (1 sp.). The Oriental subgenus Asiopsila Shatalkin is referred to Psila Meigen s. l. as a subgenus based on characters of the egg, resulting in fourteen new generic combinations: Psila (Asiopsila) brevibuccata (Shatalkin) comb. n., P. (A.) burmanica (Frey) comb. n., P. (A.) decorata (de Meijere) comb. n., P. (A.) derivata (Shatalkin) comb. n., P. (A.) formosana (Hennig) comb. n., P. (A.) freidbergi (Shatalkin) comb. n., P. (A.) humeralis (de Meijere) comb. n., P. (A.) kambaitensis (Frey) comb. n., P. (A.) limpida (Shatalkin) comb. n., P. (A.) maculipennis (Hendel) comb. n., P. (A.) michelseni (Shatalkin) comb. n., P. (A.) pleuralis (Frey) comb. n., P. (A.) primigena (Shatalkin) comb. n., and P. (A.) vittipleura (Shatalkin) comb. n.