Egg morphology and phylogeny in Arcynopterygini (Plecoptera: Perlodidae)

Comparative data are provided for eggs of nine of the 11 recognized genera in the Holarctic tribe, Arcynopterygini, and these data are used to generate a preliminary phylogeny for the group. Four generic clusters (Megarcys/Sopkalia; Frisonia/Perlinodes/Oroperla; Arcynopteryx/Neofilchneria/Skwala and Setvena/Pseudomegarcys) are established primarily from egg data, but resolution of the Frisonia and Arcynopteryx trichotomies required data from other character suites. Detailed illustrations of the epiproct complex are given for six Nearctic genera to provide additional support for the current generic classification of the group and a standardized terminology is proposed for systellognathan Plecoptera eggs.