Eronia dilatata ( Butler, 1888 )

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 : 1561-1562

Eronia dilatata ( Butler, 1888)

Kielland 1990: 266 (1 fig., as E. cleodora dilatata ). Larsen 1996: pl. 5, figs 43 i,ii (as E. cleodora ). d’ Abrera 1997: 71 (3 figs of E. cleodora Hübner, 1823 ). SI: Figure 23a–d.

Forewing length: male 34–37 mm (mean (n = 6) 35.48 mm, SD = 0.804); female 32– 39.5 mm (mean (n = 5) 35.62 mm, SD = 2.766).

Note: Aurivillius (1910b, p.62) considered dilatata to be a seasonal form of E. cleodora Hübner, 1823 . In more recent literature dilatata has been treated as a subspecies restricted to eastern Kenya and Tanzania (e.g. Ackery et al. 1995) – although Larsen (1996, p.127) considered that “the two sets of populations do not seem strongly differentiated”. However, Nazari et al. (2011), based on molecular evidence, elevated dilatata to full species status. While accepted here, in light of Larsen’ s earlier opinion this taxon would be worth further examination, notably from the standpoint of ecology and behaviour.

Records. In Tanzania found in heavy woodland and dry forests, up to 1200 m, from Pemba and coastal areas inland to Kimboza Forest, the Ulugurus, lower parts of the Rubeho Mts, Rondo Plateau, and riverine forests below Moshi and Arusha ( Kielland 1990, p.55). Listed for Lake Manyara National Park by Cordeiro (1990). The type series of E. dilatata Butler (1888, p.96) included material collected at Taveta by H.H. Johnston and by Bishop Hannington, and on Kilimanjaro by F.J. Jackson. Godman (1885, p.540) had earlier reported Johnston’ s material as E. cleodora . Also recorded from Taveta (as Teracolus cleodora ) by Rogers (1913, p.99). There is a single male in BMNH labelled “ Kilimandjaro ” apparently collected by Le Roy. Not encountered in the forest reserve zone by Liseki (2009), but on the evidence summarized here, it should be expected to occur in remnant riverine forest areas on the lower slopes.

Eronia cleodora occurs quite widely from Ethiopia to southern Africa (but is absent from West Africa). Generally, the dark wing margins of dilatata are broader than those of cleodora ( Kielland 1990) . Females vary from whitish through piebald (hindwing more yellow) to all pale yellow. Males appear invariably whitish, at least in East Africa.