Philoliche aethiopica Thunberg, 1789
description of the species
Philoliche (Wiedemann 1828) is an old world genus of horse flies (Diptera: Tabanidae) including nine subgenera and 122 species, most of which are found in Africa (Oldroyd 1957; Chainey & Oldroyd 1980). This genus represents almost all horse flies in the subfamily Pangoniinae found in sub-Saharan Africa and constitutes all but one species of the tribe Philolichini. About a dozen of the species in the subgenera Philoliche (Philoliche Wiedemann 1828, 24 species) and P. (Stenophara Enderlein 1922, 22 species) have proboscis lengths one to three times their body length. These proboscides are specialized for extracting nectar from flowers (Oldroyd 1957; Jobling 1976), and, although doubted by some (Mckeever & French 1999; discussed in Mitter 1918), females of these species still feed on blood (Mitter 1918; Tetley 1918; Sen 1931; Usher 1972; S. Morita pers. obs.). In southern Africa, several species groups in the subgenus P. (Philoliche) are involved in pollinator-mediated speciation of flowering plants (Goldblatt & Manning 1996; Johnson & Steiner 1997). In particular, the P. (P.) aethiopica species complex exhibits proboscis length variation believed to be due to local adaptation to floral resources (Oldroyd 1957; Johnson & Steiner 1995; Johnson 2000; Johnson et al. 2002; Johnson & Morita 2006; Morita 2006).
Philoliche aethiopica is distinguished from all species in the rondani clade (Fig. 3, clade B) as follows: males: eye facets of similar size; longer lappets with the dorsal process of tarsus 2 extending beyond proximal margin of tarsus 4 (Figs. 2 & 8L); females: index of frons divergence greater than 2.1 (Fig. 5). Philoliche aethiopica differs from all other species in the aethiopica species group by the presence of a distinct spot of white hairs in the center of the hind margin of the fourth segment of the abdomen. Philoliche aethiopica differs P. formosa by having a wider vertex, lacking distinct, narrow, grey sublateral stripes on the scutum and by the presence of small dark bristles covering the hind legs.
South Africa from the Eastern Cape, with older records from the Cape Fold Mountains of the Western Cape.