Charaxes (Polyura) zoolina (Westwood, 1850)

Henning 1989: 374,375 (13 figs). Larsen 1996: pl. 40, fig. 500 i,ii. d ’ Abrera 2004: 521 (4 figs). SI: Figure 14a – h.

Forewing length (all forms): male 25 – 31 mm [mean (n = 26) 28.27 mm, SD = 1.396]; female 29 – 35.5 mm [mean (n = 18) 31.83 mm, SD = 1.450]. van Someren (1974, p. 444 – 446) gave male forewing length as 28 – 30 mm in male and 30 – 32 mm in form ‘ zoolina ’, and 25 – 28 mm in male and 30 – 35 mm in female form ‘ neanthes ’.

Note: this species can be regarded as an example of class 2 polymorphism, in which both sexes occur in multiple but essentially identical colour forms – except insofar as males have only one well-developed pair of hindwing tails, whereas females always have two (Vane-Wright 1975). Intermediate colour forms also occur, with individual variation (including very darkly marked males originally named as subspecies obscuratus Suffert,

1904); it seems likely this is more a case of seasonal polyphenism rather than genetic polymorphism.

Records

Kielland (1990, p. 112) indicates that this butterfly can be found in most parts of Tanzania, at altitudes up to c. 2100 m, usually in thorn-bush but also entering montane forests where its primary habitat is adjacent. Cordeiro (1990, p. 35) noted it as common in Lake Manyara National Park. Recorded [as the synonym Charaxes neanthes (Hewitson)] by Butler (1901, p. 24) from Taveta. OUMNH has six males and three females from Taveta, c. 2500 ft, collected by Rogers in 1905/06 – all are f. ‘ zoolina ’, not f. ‘ neanthes ’. The BMNH collection includes a male from West Kilimanjaro, 4500 – 5000 ft, May – July 1938, and a female from Moshi, 2500 ft, January – February 1938, both collected by B. Cooper, and both f. ‘ neanthes ’. Not encountered in the forest by Liseki (2009), so included here as a member of the lower slopes.

Charaxes zoolina occurs widely is eastern Africa, from Somalia to South Africa. Three additional subspecies have previously been recognized – of which one occurs in Madagascar, and another in Angola. The third, C. z. mafugensis Jackson, 1956, is found in montane forests in Rwanda and southwest Uganda (Henning 1989, p. 376; Ackery et al. 1995, p. 463), and Rumanyika Orogundu Game Reserve in the bordering Karagwe District of western Tanzania (Kielland 1992, p. 51). However, molecular evidence now suggests all four could be regarded as specifically distinct (Vingerhoedt et al. 2009).