Plecoptera (Insecta): recording the diversity and integrating morphological and molecular data

Abstract

Plecoptera is an order of aquatic insects that occurs mainly in clean, fast and well-oxygenated streams. This order, together with Ephemeroptera, Megaloptera, Neuroptera and Trichoptera were inserted by Linnaeus in 1758 in the Systema Naturae in Neuroptera, but in the 19th century they gained the status of order. Plecoptera has approximately 3700 species described in 16 families. Despite the efforts made in recent years in an attempt to better understand the diversity of this order, we still know little about: 1) the intraspecific morphological/molecular variability, since most species were described based on few individuals; 2) the nymphs, since most species were described based only on male adults; 3) the biology and actual geographic distribution of species; and 4) the phylogenetic relationship between species and supraspecific groups. In this context, expanding knowledge on these themes is a great challenge for researchers in Brazil and in other South American countries. (AU)