Differences between Ch. nigrescens and Ch. ndebele These two South African species are similar in general appearance of larvae, subimago and imago and most reliably differs by the following characters: In larva: Labrum in Ch. ndebele has usual shape (Figs 22–24), in Ch. nigrescens —with unusually deep median incision (Fig. 20). Other larval characters distinguishing these species are setation of legs, denticles on abdominal terga and shape of sternum IX in male (see above). In winged stages (subimago and imago of any sex): Hind wing in Ch. ndebele has usual shape (Fig. 73), in Ch. nigrescens —with unusually reduced apical part (Fig. 75). In male imago (besides hind wing structure), Ch. ndebele and Ch. nigrescens differ by structure of penis (Figs 78 and 82). In female subimago and imago (besides hind wing structure): Egg of Ch. ndebele has two polar caps consisted of large papillae pressed together; hidden longitudinal rods are undulate, with a row of vesicles between rods of each pair (Figs 90–98). Egg of Ch. nigrescens has no polar caps; its hidden rods are straight, and vesicles are absent (Figs 84–89). Eggs of these two species can be distinguished using light microscope.

Published as part of Kluge, Nikita J., 2025, Redescriptions of Choroterpes nigrescens Barnard 1932 and Ch. ndebele Agnew 1962 with notes about egg structure of Choroterpes Eaton 1881, Megaglena Peters & Edmunds 1970 and Klugephlebia Selvakumar et al. 2016 (Ephemeroptera, Leptophlebiidae), pp. 203-222 in Zootaxa 5711 (2) on pages 215-217, DOI: 10.11646/zootaxa.5711.2.3, http://zenodo.org/record/17883329