Stonefly Species Soyedina vallicularia (Tiny Winter Blacks)

Source: Soyedina Ricker, 1952 (Plecoptera: Nemouridae) in the eastern Nearctic: review of species concepts, proposed morphology-based species groups, and description of a new species from North Carolina

Three species are proposed for this group: Soyedina alexandria, Soyedina calcarea, and Soyedina vallicularia. In ventral aspect the epiproct dorsal sclerite is open distally, revealing a sclerotized inner member which is flanged, directed laterally, and flange lip is enlarged (Figs. 2 – 4, 10 – 12, 18 – 20). The paired ventral sclerites are asymmetric with right member distinctly longer than left (Figs. 1 – 2, 9 – 10, 17 – 18). The paired dorsal sclerites are also asymmetric (Figs. 5 – 6, 13 – 14, 21 – 22). The outer paraproct lobes are variable between species but all lack any form of an anteriorly-directed flap or spur (Figs. 7, 15, 23). This is the only group with distributions extending westward from the Appalachian Mountains across the Great Lakes region, into the Ohio River and Tennessee River basins, and west of the Mississippi River (Fig. 79).