Stonefly Species Alloperla nanina (Sallflies)

Source: Alloperla clarki sp. nov. (Plecoptera: Chloroperlidae), a new species from the eastern Nearctic with discussion of a new species group

Amended description – Male. Tergum 10 divided mesally by epiproct and reduced cowl into two hemitergal lobes; lobes bearing dense matting of long setae (Figs. 13 – 15). Epiproct length (L) 125 µm, maximum width (MW) 40 µm, L: MW ratio = 3.2. In dorsal view the epiproct is widest in basal 1/3, tapering anteriorly and distally. The entire dorsal surface is bare (Figs. 14 – 17). The apical notch is narrowly triangular and extends anteriorly and ventrally as a groove between paired, serrated apical margins (Figs. 15 – 18); 10 distinct teeth are present (Figs. 17, 21 – 22); the serrated apex is arcuate ventrally (Figs. 19 – 22). The epiproct stem is secondarily reduced and nearly absent; the serrated portion comprises the entire lateral profile (Figs. 19 – 22). Dense hair matting is also absent laterally; a sparse group of long hairs are present in medial 1/3 (Figs. 20 – 22). The adults of Alloperla nanina are unusual amongst eastern Nearctic Alloperla species in that the pronotum has a charcoal gray pigmentation within the medial 75 % of the segment (the entire margin is pale yellow in color), the mesonotal and metanotal scutellar margins are darkly pigmented, and the abdomen has darkened medial and lateral stripes (Surdick 2004, Grubbs & Singai 2018, their fig. 15).