Neoperla biserrata, Zwick & Zwick, 2023

Zwick, Peter & Zwick, Andreas, 2023, Revision of the African Neoperla Needham, 1905 (Plecoptera: Perlidae: Perlinae) based on morphological and molecular data, Zootaxa 5316 (1), pp. 1-194 : 110-111

48. Neoperla biserrata n. sp.

(Figs. 267–271)

Type material studied. Federal Republic of Nigeria, Holotype ♁: W. Afrika, Benuë, Dr. Houy leg. 28.12.1912 (in poor shape; penis on slide; MfNB).

Habitus. WL 7.8mm, Rs with 3 branches. Ocelli large, separate by their own diameter. Faded, pale yellowish.

Male. Hind tibiae unmodified. T7 with slender pyramidal caudal process. Sclerite on T8 Y-shaped, caudally from a raised hump band-shaped. Opposed faces of T7 and T8 armed with SB (Fig. 268). Lateral pilose swellings of T9 with a few SB, median furrow bare. HT10 short, slender and curved little, tip pointed, mediobasal callus tongue-shaped (Fig. 267).

Penis a straight smooth tube, ventrally with subterminal membranous bulge with 2 parallel groups of spines (Figs. 269–270). Everted endophallus base carrot-shaped, with scattered sharp spines. Distally the endophallus is a long slender tube with 2 regular rows of triangular spines which resemble saws (Fig. 271). Spines grow smaller and disappear near the end.

Female. Not known.

DNA. No data.

Notes. The long and narrow tubular endophallus with two regular rows of teeth is shared with several members of the N. spio -cluster. Neoperla biserrata n. sp. stands out by the subapical spinose swelling of the penis tip and the wide basal section of endophallus. The presently unknown female of N. biserrata n. sp. is probably similar to other females in the same cluster, i. e., with marks on S8, a long thin SSt, and eggs with numerous straight striae. The morphology of females without known males in this complex excludes them as probable female of N. biserrata n. sp., possibly except N. benti n. sp., which was, however, found far from Nigeria.

Etymology. The adjectival name alludes to the pair of saw-like rows of triangular teeth on the endophallus.