Neoperla (Borneella) Zwick 2023, new subgenus

2.4.2.1. Neoperla (Borneella), new subgenus

Type species: N. bilobata Zwick, 1986; additional included species: N. borneensis (Enderlein, 1909), N. furcata Zwick, 1986, N. furcifera Klapálek,1909, N. harina Navás, 1929, N. naviculata Klapálek,1909.

Male: T7 with a deeply divided flat process or a pair of adjacent processes, sharp spines (modified sensilla basiconica?) along the margins. T8 flat with a band of spinules under each projection of T7, small spinule groups or pilose humps on T9. HT10 with a caudal extension that bears grouped setulae along the medial edge (e.g., Figs. 46, 48). Penis base membranous and soft except for a small ventral and an elongate pointed dorsal sclerite. The endophallus varies from short and curved with some protruding lobes (Fig. 49), to very large bizarre shapes with several large lobes or long fingers, the largest spines at the tips.

Known females: No or a short subgenital plate. Vagina with minute pale spicules in center, otherwise unmodified, topped by a stack of approximately circular folds. The short spermathecal duct and the sausage-shaped spermatheca insert on top.

Known eggs are not striate but have irregular punctures or polygones, with or without collar, anchors are multifilamentous, each filament ends in a small adhesive body (Fig. 47).