Phylogeny of the Plecoptera: Past Challenges, Recent Developments, and Future Direction

Phylogenetic study of the Plecoptera has been a challenge for stonefly systematists for over a century. Numerous competing hypotheses supported by morphological and/or molecular evidence have shown incongruent or unresolved topologies. However, the advent of genomic and transcriptomic molecular phylogenetics has facilitated the generation of well-supported and fully-resolved phylogenies. Within the superfamily Perloidea, recent study has recovered a separate family level lineage for Kathroperla Banks, 1920, a genus historically included in the subfamily Paraperlinae within the family Chloroperlidae. Combined molecular and morphological evidence support elevation of Kathroperla to Kathroperlidae, the seventeenth family of extant Plecoptera. Other recent study has provided new phylogenetic insights into the superfamily Nemouroidea and the biogeographjc history of all extant families. Additionally, mitochondrial genomes have been used to construct numerous well-supported family level phylogenies. Although recent studies provide new phylogenetic perspectives, incongruence between hypotheses still exists. A future global collaborative effort aimed at analysis of genomic and/or transcriptomic datasets generated from previous recent studies combined with newly generated molecular data from key taxa could provide a robust phylogeny of the world fauna.