Phylogenetic analysis of Lachesilla Westwood (Psocodea: Psocomorpha: Lachesillidae) and relationships of sister genera of the subfamily Lachesillinae.

Abstract

Lachesilla is the most species-rich psocid genus, with 341 species grouped into 19 species groups (with at least 100 undescribed species), plus an additional undescribed species group. We present the first phylogenetic analysis of Lachesilla and a discussion on the relationships of sister genera of the subfamily Lachesillinae. We codified a matrix of 60 morphological characters (16 multistate and 44 binary) formed by 44 terminals: 37 ingroup species and seven outgroup species. A phylogenetic analysis was performed using Maximum Parsimony (MP) as optimality criterion, under equal weights and implied weights approaches. Monophyly of Lachesilla is not recovered, showing a polyphyletic genus divided in two major clades: clade A, composed of the pedicularia species group + Nadleria, and clade B, including the remaining species groups. The implied weights analysis produced a hypothesis with Hemicaecilius as sister group of clade B, nesting seven subclades mainly with low branch support values (symmetric resampling and bootstrap). These results suggest that all species groups, included in this analysis, can be considered monophyletic clades based on several synapomorphies, despite the andra species group was split up showing that L. punctata + L. dentata cluster together with high branch support values, but L. tehuautlensis and L. falcicula were recovered in different subclades.