Neoperla arambourgana, Navas, 1936

V.2. The Neoperla arambourgana View in CoL -complex (= clade L)

This complex includes N. arambourgana , N. dundoana n. sp., and N. leroiana . Sternites of males are unmodified, the middle of T7 is slightly raised caudally, and the elevated part is slightly concave between low paramedian humps. T8 has a forward-curved process or a strong hook. Males also share an inconspicuous process between the lateral humps on T9; it is most distinct in N. arambourgana ( Fig. 459 View FIGURES 459–465 , black arrow). The straight tubular penis narrows distally a little, the tip is soft, often annulated and curved. The everted endophallus curves ventrad.

In most African Neoperla , spines on the basal section of endophallus are distributed dorsoventrally. In the present group the largest spines form two lateral rows near the base there are no other spines. Distally, smaller spines appear between the rows. Distally, all spines disappear but transparent membranes and a thin thread extend back to near the basal penis foramen. Details were not visible by transparency; the penes of a few specimens were therefore broken and the endophallus extracted ( Fig. 438 View FIGURES 432–438 ). The extracted middle portion of the endophallus resembles a very wide trachea. In several preparations the terminal structures appear to be somewhat inflated.

Caudal edge of female S8 variable, with a sclerotised nail or notch. Vagina unmodified, the SSt is a densely spinose slender tube of uniform width and moderate length, forming 1.5–~4 rings. The ovoid eggs have numerous straight or levogyrous striae, the bare costae are wider than the narrow sulci which are impunctate, except two rows of micropunctures.

The monophyly of the N. arambourgana -complex (= clade L) is maximally supported (100/100/100) by the DNA sequence data analyses ( Figs. 491–492 View FIGURE 491 View FIGURE 492 , 497 View FIGURE 497 ). Its sister group relation to the N. sjostedti -complex (clade K) is also maximally supported (100/100/100).