Phylogenetic analysis of Rhagovelia Mayr, 1865 (Insecta: Heteroptera: Veliidae) from the Americas
Gerromorpha, phylogeny, semiaquatic bugs, Nearctic region, Neotropical region
Members of the genus Rhagovelia Mayr, 1865 (Hemiptera: Heteroptera: Gerromorpha:
Veliidae: Rhagoveliinae) are commonly found in tropical aquatic habitats, forming the
dominant guild of predatory insects of the neustonic fauna. In the Americas alone, there are
about 200 described species. The genus is easily recognizable by the distal tarsomere of the
middle leg deeply cleft and bearing a feathery fan. Currenly, the American fauna of
Rhagovelia is subdivided into 18 species groups, which in turn compose one grade and five
complexes, in addition to species without defined position. Despite being recovered as
monophyletic in all phylogenetic analyses performed so far, the relationships between such
supraspecific groups and their monophyletic conditions have never been truly tested. By
examination of the literature and 300 specimens, representing the taxonomic groups defined
in previous works, 10 characters already used in publications, 20 characters adapted from
the literature and 16 new characters were selected, totaling 46 discrete morphological
characters, being 38 binary and 8 multistates. Phylogenetic analyses were performed through
heuristic search using TNT 1.6 no taxon limit and by Bayesian Inference using MrBayes
3.2.2. The monophyletic conditions of the following clades have been recovered: genus
Rhagovelia, subgenus Trochopus Carpenter, 1898 stat. nov., angustipes, collaris, obesa,
robusta and varipes complexes, and cali, elegans, hambletoni, hirtipes, itatiaiana, lucida,
obesa, salina, secluda, tayloriella, torquata, varipes and whitei groups. The following groups,
however, are not monophyletic: ainsliei, armata, bisignata, robusta and spinigera. Rhagovelia
gaigei Drake & Hussey, 1957 and R. roldani Polhemus, 1997 did not cluster with any
supraspecific group, forming successive terminal branches close to (robusta complex +
Trochopus). Recovering the usage of the subgenera Rhagovelia s. str. and Trochopus is
suggested, as well as name changes, from bisignata group to angustipes group, from
tayloriella group to collaris group and from torquata group to abrupta group.