Systematics of the meniscus midges (Diptera: Dixidae) molecular phylogenetics of world taxa and highlights from revisionary studies of Nearctic Dixa Meigen
Moulton, J. K.  2018.  Proceedings: The 9th International Congress of Dipterology, Orlando, FL, September 25-30, November 2530, Windhoek, Namibia.

Abstract:
Meniscus midges comprise a small family of ca. 200 described species of aquatic, mosquito-like, culicomorphan Diptera. Larvae move in a characteristic sidewinding fashion, ultimately resting in a U-shaped position on emergent substrates at the atmosphere and water interface, hence the common name. There they actively filter fine particulate organic matter from the water column. Pupation occurs on emergent substrates. Adults, which possess denuded wings having a strongly arched vein R2+3, do not feed and typically remain for a short period near the preimaginal habitat, which can be lotic or lentic. Eight extant genera Asiodixa Papp, Dixa Meigen, Dixella Dyar & Shannon, Meringodixa Nowell, Mesodixa Belkin, Heinemann & Page, Metadixa Peters, Neodixa Tonnoir, and Nothodixa Edwards are currently recognized. The higher classification of the family remains largely unsettled and no modern phylogenetic analysis has been conducted. This presentation highlights results from: 1) phylogenetic analyses of nucleotides from large portions (ca. 3 kilobases) of two nuclear loci, big zinc finger and 5intG, acquired from a diverse assemblage of world species and 2) revisionary studies of Nearctic species of Dixa Meigen utilizing a combined molecular and morphological approach. Implications the resulting trees have upon current supraspecific concepts will be discussed as well as how nuclear DNA fingerprinting has impacted descriptive studies, ranging from simple life stage association to identification and elucidation of cryptic species complexes.