Abantis venosa Trimen 1889

Cock, Matthew J. W. & Congdon, T. Colin E., 2011, Observations on the biology of Afro-tropical Hesperiidae (Lepidoptera) principally from Kenya. Part 2. Pyrginae: Tagiadini 2893, Zootaxa 2893 (1), pp. 1-66 : 60

Abantis venosa Trimen 1889 ( Figures 54–55 )

Evans (1937) treated A. venosa as a series of forms and subspecies covering most of southern Africa, but his two subspecies are now recognised as valid species: A. elegantula Mabille from West Africa and A. contigua Evans from central Africa and East Africa including western Kenya. The species group would benefit from a careful examination of the purported forms linked to observations on the food plants and early stages. As currently defined, A. venosa is found from Uganda, and the Kenya coast ( Larsen 1991), south through Zaire and Zambia to South Africa, but the status of the different forms has not been evaluated. For example, TCEC notes that this is a variable insect, and has reared dark specimens from the Sabaga River, Mpanda, and much lighter ones from Madibira on the Iringa/Mbeya border.

In Tanzania, A. venosa is common in the Brachystegia woodlands of western Tanzania ( Kielland 1990), but rare in eastern areas. Cooper (1973), Kielland (1990) and Larsen (1991) all record that this species is attracted to flowers, and Cooper (1973) also associates it with slopes and peaks of rocky hills.

Dollman (unpublished) found caterpillars of A. venosa at Solwezi, Zambia, on two occasions, feeding on “ndombe” (unidentified), but did not paint the caterpillar. Pringle et al. (1994), Henning et al. (1997) and Heath et al. (2002) record the food plants as Pterocarpus brennanii and P. rotundifolius (Fabaceae) in southern Africa, based on observations by Paré, according to the first of these sources. Larsen (2005) repeats this food plant genus for A. venosa (under A. elegantula ). In the insect collection of the Ukiriguru Agricultural Research Institute, I noted a label over the name Abantis venosa : “Biharamulo [Kagera, Tanzania], cashew, 18 Jul 1959, I.A.D. Robertson, 4087” without a specimen. There are no other records of A. venosa or other Abantis spp. from cashew, Anacardium occidentale (Anacardiaceae) , so this possible record needs confirmation. TCEC has reared this species from Pterocarpus tinctorius (Fabaceae) , and considers that it probably also feeds on other species of Pterocarpus in Tanzania.

Pringle et al. (1994) quote Paré that the caterpillar is very similar to that of “ A. arctomarginata ” (i.e. A. bamptoni ), but the dorsal plate T1 is brown not black; the body is “off white with clusters of yellow spots laterally on each segment”. Henning et al. (1997) illustrate the caterpillar; it is pale grey with clusters of yellow spots on the anterior margin of segments A2–A7 and maybe A8. We only have a photograph of the prepupa from Tanzania ( Figure 54 ), in which the body has lost most of its colour, although the yellow spots can just be made out. The caterpillar is therefore rather similar to those of A. arctomarginata ( Figure 37 ) and A. bamptoni ( Figure 40 ).

The photograph of the pupa is unfortunately overexposed in Figure 55 , and as it is newly formed no conclusion about the markings can be drawn. However, the brown, bifurcate frontal projection is clear. There are three empty pupae in the NHM from the Dollman collection, unfortunately all missing the frontal projection: brown spot around base of projecting brown spiracle T1, extending onto collar; abdomen with dark brown dorsolateral spots on A1, A4–A6; dark brown spot around pale brown spiracles A4–A8; a light covering of white waxy powder, the wing veins more of less marked by the absence of wax.

Figures

FIGURE 37. Final instar caterpillar of Abantis arctomarginata on Uapaca kirkiana (TCEC). 1, dorsal view; 2, dorsolateral view.

FIGURE 40. Final instar caterpillar of Abantis bamptoni (TCEC) collected on Uapaca kirkiana, 18 Nov 2003, Mutinondo Wilderness, Mpika, Zambia. 1, dorsal view; 2, lateral view.

FIGURE 54. Prepupa of Abantis venosa collected on Pterocarpus angolensis 20 Mar 1994, Sabaga, western Tanzania, dorsolateral view (TCEC).

FIGURE 55. Newly formed pupa of Abantis venosa collected as prepupa on Pterocarpus angolensis 20 Mar 1994, Sabaga, western Tanzania, photographed 21 Mar, dorsal view (TCEC).