Bicyclus maesseni Condamin
Creators: name: Brattström, Oskar
name: Aduse-Poku, Kwaku
name: Collins, Steve C.
name: Brakefield, Paul M.
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Nymphalidae
Bicyclus
Bicyclus maesseni

description: Bicyclus maesseni Condamin
(Figs. 11–14, 27, 31)
Bicyclus maesseni Condamin 1971 (Lipke Mate, Ghana)
Material studied. 79 ♂ & 127 ♀. See Supplementary Table 1.
Diagnosis. The male (Fig. 11) has two well defined androconial structures (apart from the normal brush in the hindwing cellular area) that set it apart from the other species in the group (Fig. 14). Just as in B. ignobilis a part of vein 1b on the dorsal hindwing is enlarged, but in B. maesseni the enlarged part is much shorter and wider, forming a distinctive bulge close to the base of the wing. There are no long black hairs covering this structure (as found in B. ignobilis). There is also a quite distinct androconial structure located basally in space 1b, immediately above vein 1, on the dorsal forewing. It is formed by a patch of scales being slightly lighter than the dark base colour, and the basal part of the patch is covered by a loose collection of short hairs. Both sexes (Figs. 11–12) also stand out from similar sympatric species by the heavily darkened veins crossing through the apical patch on the forewing, breaking the patch up in at least two or more separate light subunits.
Distribution. West Africa between Sierra Leone and western Nigeria (Fig. 27). This species was previously thought to occur mainly in the Volta region in Ghana and in eastern Ivory Coast. However, a range of new records has recently been acquired from Liberia and Sierra Leone, as well as many more sites in Ghana, often in sympatry with B. ignobilis. Despite all of these new records B. maesseni is still the only representative of the group in the forests of the Volta region, where it can be reasonably common in the wetter areas. There is also a single specimen from Okomu in western Nigeria, collected by J. Wojtusiak in 1986 and kept in the MZUJ collections (T. Larsen & T. Pyrcz Personal Communication). We have investigated detailed photos of this specimen and it is clearly a male of B. maesseni. At first this might appear improbable, but in reality most species that are found in Volta also extend their distribution eastwards across the Dahomey gap into Western Nigeria and often further onwards to the east (Larsen 2005). This suggests that the gap opened up well after most current western rainforest species was already dispersed on both sides of its current borders. It is therefore not impossible that the Okomu specimen is a representative from a small relict population in Western Nigeria. Okomu is one of the better-surveyed parts of this area so it is surprising that no other specimens have been previously found, but B. maesseni might just be incredibly rare east of the Volta region. As most forests in western Nigeria are now lost we might not be able to ever know if the species perhaps used to be more widespread until very recently.
Comments. We did not investigate the type material that is kept in MNHN, but the images in the original description (Condamin 1971) are very clear, leaving no doubt about the morphological characters defining the species.
description: Published as part of Brattström, Oskar, Aduse-Poku, Kwaku, Collins, Steve C. & Brakefield, Paul M., 2015, Revision of the Bicyclus ignobilis species-group (Lepidoptera: Nymphalidae: Satyrinae) with descriptions of two new species, pp. 57-79 in Zootaxa 4018 (1) on pages 65-68, DOI: 10.11646/zootaxa.4018.1.3, http://zenodo.org/record/289462