Philoliche (Philoliche) aethiopica (Thunberg, 1789)

Morita, Shelah, 2008, A revision of the Philoliche aethiopica species complex (Diptera: Tabanidae), African Invertebrates 49 (1), pp. 129-158 : 152-153

Key to species in the Philoliche (Philoliche) aethiopica species complex

1 Holoptic: eyes meeting or nearly meeting in front (males) .................................. 2

– Dichoptic: eyes clearly separated, not touching or close to touching at any point (females) ............................................................................................................... 3

2 Fore tarsi with long process on first and second segments (lappets); eye facets all of similar size or only gradually increasing in size from ventral to dorsal; eyes meeting until slightly above antennae leaving a small triangle of a frons (aethiopica group).................................................................................................................... 4

– Fore tarsi without long process on first and second segments; if process exists, it does not extend beyond the distal margin of the third tarsomere; eye facets abruptly increasing in size from ventral to dorsal forming a demarcating, horizontal line; eyes contiguous to near the base of antennae, no vestige of frons remaining (rondani group).................................................................................................................... 5

3 Ratio of frons width at base to frons width at vertex greater than or equal to 2.1 ( Fig. 3b ) (aethiopica group) ................................................................................. 4

– Ratio of frons width at base to frons width at vertex less than 2.1 ( Fig. 3a ) (rondani group).................................................................................................................... 5

4 Dorsum of mesothorax with distinct, narrow, grey sublateral stripes. Females: females are not yet known for this species; this is their provisional outcome in this key as predicted by the distribution of other characters in the group ..................... ................................................................................................... formosa (Austen)

– Dorsum of mesothorax without stripes, or with indistinct, broad, dull reddish or greyish ones ....................................................................... aethiopica (Thunberg)

5 Dorsum of mesothorax with grey band on lateral margins and with grey on posterior margin; scutellum greyish pink ( Fig. 1 ) ............................................................... 6

– Dorsum of mesothorax with grey band on lateral margins, but not on posterior margin; scutellum concolourous with centre of mesothorax, not greyish pink .... 7

6 Grey posterior margin of mesothorax sharply contrasting with brown at centre; frons generally light coloured and pollinose, not wholly shiny ( Fig. 1b ) .... elegans (Bigot)

– Grey posterior margin of mesothorax gradually blending into brown anteriorly; frons generally dark and shiny. If frons pollinose, then only along eye margin ( Fig. 1a ) ....................................................................................... rubiginosa Dias

7 All legs similarly coloured on proximal segments: coxae grey, paler dorsally and with white hairs; trochanters black; femora orange. Posterolateral margin of segments 4 and 5 with tufts of black or white hairs as follows: 4 – white only, 5 – black and white ....................................................................... rondani (Bertoloni)

– Fore and mid legs similarly coloured, hind legs different: fore and mid coxae grey to pinkish grey, paler dorsally and with white and a few black hairs, trochanters black; hind coxa yellow, trochanters orange; fore and mid femora orange, hind femur yellow, same as hind coxa. Tibia of foreleg and midleg paler than femora. Hind tibia darker than hind femur, with black hairs. Posterolateral margin of segments 4 and 5 with tufts of black or white hairs as follows: 4 – black and white, 5 – black only. Third abdominal segment relatively paler dorsally than the other abdominal segments. Proboscis usually 2× greater in length than P. rondani . Known from the Albany Centre of endemism only......... umbratipennis (Ricardo) stat. rev.

Figures

Fig. 3. Frons divergence in females of (a) P. rondani and (b) P. aethiopica. The index of frons divergence is the ratio of the width of the frons at the clypeal suture (cs) to the width of the frons at the vertex (v). Note also that most P. aethiopica also have an obtuse angle in the inner eye margin (ea), though this is variable.

Fig. 1. Dorsal view of (a) Philoliche rubiginosa and (b) P. elegans showing differences in patterning of the mesoscutum and frons. White arrows point to the transition between colouring of the grey hind margin of the mesoscutum and the main part of the mesothorax.