First phylogenetic analysis of the family Neriidae (Diptera), with a study on the issue of scaling continuous characters

Abstract

Neriidae are a small family of acalyptratae flies, mostly distributed along the tropics. Very little is known about their biology, and the evolutionary relationships among species have never been evaluated. We perform the first comprehensive phylogenetic analysis of the family, including 48 species from all biogeographic regions inhabited, as well as five species of Micropezidae and one Cypselosomatidae as outgroups. We build a morphological data matrix of 194 characters, including 72 continuous characters. We first explore ways to deal with the issue of scaling continuous characters, including rescaling ranges to unity and using implied weighting. We find that both strategies result in very different phylogenetic hypotheses, and that implied weighting reduces the problem of scaling, but only partially. Furthermore, using implied weighting after rescaling characters improves the congruence between partitions and results in higher values of group support. With respect to the Neriidae, we confirm the monophyly of the family and of most its genera, although we do not obtain any of the currently accepted supra-generic groups. We propose to restrict the Eoneria and Nerius groups exclusively to the Neotropical fauna, and synonymyze Glyphidops subgenus Oncopsia Enderlein with Glyphidops subgenus Glyphidops Enderlein, eliminating the subgenera of the latter. This revised phylogeny presents a striking biogeographic consistency, and shows that previous main divisions of the family were based on events of convergence.