Calliphora croceipalpis Jaennicke 1867
A typical Calliphora species with dark yellow anterior spiracle and brownish black (not orange-yellow) basicosta. Anterior part of genal dilation uniformly black, hairs on genal dilation and postgena predominantly black.
Frequently confused with the alien C. vicina, but told by colouration of basicosta and genae.
Distribution: DR Congo, Eritrea, Ethiopia, Malawi, Rwanda, South Africa, Tanzania, Zimbabwe. Widespread from East to South Africa.
The common name "Highveld Blowfly'' is misleading, it is not restricted to the South African highveld, many records from coastal Cape and elsewhere. Prins 1982 provides the common name "cadaver fly" which may be a better fit.
Original description in:
Jaennicke , J. F. 1867. Neue exotische Dipteren. Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft 6
https://www.biodiversitylibrary.org/item/84507#page/394/mode/1up
Key and photos in:
Lutz, L., Williams, K.A., Villet, M.H. et al. Species identification of adult African blowflies (Diptera: Calliphoridae) of forensic importance. Int J Legal Med 132, 831–842 (2018). https://doi.org/10.1007/s00414-017-1654-y
Good illustrations and redescription in Prins 1982:
https://www.biodiversitylibrary.org/page/40763851#page/241/mode/1up
https://www.biodiversitylibrary.org/page/40763851#page/242/mode/1up
For a detailed description of the adult see Zumpt (1956, 1965). Head and thorax blackish blue to
steel blue, almost dull; abdomen more greenish blue and almost shiny and with whitish pollinosity forming large patterns; dark iridescent transverse band present on posterior border of each abdominal segment. Tuft of strong setae present on each side of first visible abdominal segment, just before its posterior border. Four short distinct vittae present on anterior half of presutural area of mesonotum, indistinct over rest of mesonotum. Reddish colour of basal parts of third antennal segments and orange colour of palpi very characteristic. In the males, frontal stripe narrowed by eyes and there are only two vertical bristles, outer verticals (present in female) being absent. Normal length 9-12 mm.
Widely distributed throughout the Subsaharan region, except probably the western parts of Africa. It is common in South Africa and also occurs on some of the islands along the west coast such as Dassen Island.
Biological note: quoted from Prins 1982:
According to observations made during surveys along the coastal areas from Mossel Bay to Port Nolloth, C. regalis infests mainly large animals such as eland and gnu, whereas C. croceipalpis was seen to infest bird carcasses and some of the smaller mammals such as rats and dassies; occasionally, however, its larvae were recovered from larger animals such as gnu, but very few adults were reared in these cases due to competition by C. albiceps (Wiedemann), C. chloropyga (Wiedemann), and C. megacephala. Both these species infest human cadavers, C. croceipalpis apparently mostly during the winter and early spring, and C. regalis mostly during the warmer autumn months."
iNat observation: https://www.inaturalist.org/observations/229694335