Dixeia doxo costata Talbot, 1943

Liseki, Steven D. & Vane-Wright, Richard I., 2014, Butterflies (Lepidoptera: Papilionoidea) of Mount Kilimanjaro: family Pieridae, subfamily Pierinae, Journal of Natural History 48 (25 - 26), pp. 1543-1583 : 1570-1571

[ Dixeia doxo costata Talbot, 1943 ]

Larsen 1996: pl. 10, figs 91 i,ii. d’ Abrera 1997: 105 (supposedly 5 figs – but at least one of these is D. charina liliana from Taveta).

Note: As already discussed under D. charina , based on exophenotypic characters alone, these two variable species can be very difficult to separate. As we do not consider that D. doxo costata occurs on Kilimanjaro we do not present images or size data, but it appears that the more western doxo costata is significantly smaller in forewing length compared with D. charina liliana .

Talbot (1943b) considered D. doxo and D. charina to represent variants of a single species. Kielland (1990) recognized charina and doxo as separate, citing both D’ Abrera (1980) and Carcasson (1981) as authorities. Larsen (1996, p.144), following d’ Abrera (1980, p.90, 1997, p.104) and Ackery et al. (1995, p.211), incorrectly cited Bernardi (1961) as the source of the division, commented on confusion in the literature(!), and further suggested that the reality might be more complex, with various morphs potentially representing several allopatric species.

Bernardi (1954) is the correct reference for the genitalic division of these taxa as separate species. In the more western D. doxo , the valve and phallus are relatively short, whereas in the more eastern D. charina both are relatively long. In making this distinction, Bernardi (1954) acknowledged van Son (1949: figs 94, 96), who illustrated exactly the same differences but nonetheless treated the two in South Africa as conspecific (as D. doxo charina and D. doxo parva Talbot , in the local fauna). In this context it is interesting to note that Bernardi (1958), in naming a new subspecies from southeast Ethiopia having the charina genital phenotype, chose to include it likewise under an umbrella D. doxo – potentially giving rise to confusion. In effect, Bernardi regarded doxo as a superspecies ( D. doxo s.l.) with two semispecies, D. doxo s.s. and D. charina .

In Tanzania, Kielland (1990, p.63) considered D. charina (as subspecies dagera) to be limited to “coastal areas”, whereas the two subspecies of doxo that he recognized occurred inland. Of these, he noted D. d. costata from savannah and forest edges “from near sea level to 1200 m ”, with records from the region of Dar es Salaam south to Kisiju, and inland to Mikumi, and to Morogoro (which lies about 400 km south of Kilimanjaro), and subspecies D. d. alberta (Grünberg, 1911) from “central to northcentral Tanzania ”. We believe that Kielland’ s records for “doxo costata” must refer to D. charina liliana . Bernardi (1954: fig. 2) recorded doxo costata from Lake Manyara National Park, 140 km west of Kilimanjaro, based on dissection of the male genitalia; Cordeiro (1990, p.28) recorded both doxo costata and charina liliana from Lake Manyara as “common”; and Moehlman and Liseki (2003) also noted both species from LMNP, based on “literature” (e.g. Cordeiro 1990). Bernardi (1954) was unable to dissect alberta; this taxon is currently treated as a subspecies of doxo from eastern DRC, and central and northwestern Tanzania. Talbot (1943b), in describing costata from extensive material in BMNH and OUMNH, noted it from Kondoa in the Great Craters area, Kasanga (Lake Tanganyika), and various localities in western Kenya and Uganda – but certainly not from eastern Tanzania. This may explain why Kielland (1990, p.64) commented that he had “not come across it [costata] in northern Tanzania, but the coastal population agrees with costata ”. On exo-phenotypic grounds, D. charina liliana and D. doxo costata are very similar in appearance.

Currently we see no convincing evidence that true D. doxo sensu Bernardi (1954) occurs on Kilimanjaro or its lower slopes.