Apolysis hesseana Evenhuis & Greathead, 1990

Greathead, David J., 2006, New records of Namibian Bombyliidae (Diptera), with notes on some genera and descriptions of new species, Zootaxa 1149 (1), pp. 1-88 : 5-6

Apolysis hesseana Evenhuis & Greathead

Apolysis hesseana Evenhuis & Greathead, 1999: 6 . New name for Apolysis namaensis ( Hesse, 1975: 289) preoccupied by Hesse (1938).

A pupa of an Apolysis sp. containing a pharate adult was described by Greathead (1999). This specimen was reared from the nest of a Quartinia sp. ( Hymenoptera : Vespidae : Masarinae ) in the empty shell of Trigonephrus sp. ( Gastropoda : Dorcasiidae ). Based on the shape of the antenna of the pharate adult inside the pupal cuticle, it was considered that the specimen was probably A. capicola Hesse. However , now that a series of adults of both sexes have been reared from a collection of Quartinia sp. nests in Trigonephrus sp. shells it was possible to make a firm identification of the Apolysis sp. as A. hesseana .

A. hesseana was described briefly from a single female collected in South Africa (Northern Cape) in comparison with A. lactearia Hesse. The holotype has been examined and compared with a series of reared specimens from Namibia . It is apparent that the holotype is somewhat denuded but that the reared specimens belong to the same species. A more complete description is provided below so as to adequately characterise this species for which host records are available.

Description. Males. Entire body black densely ash grey tomentose and largely covered with long, coarse, upstanding white hairs. Length 2.5–3.0 mm; proboscis ± 2 mm. Head: holoptic with frons represented only by a small triangular area above antennae. Antennal ratio 1.5:1:4; with minute white hairs on scape; first flagellomere ovoid broadest at middle and spine­like second flagellomere almost terminal. Proboscis black, narrow and with palpi less than length of antennae, usually concealed in oral cavity. Thorax: mesoscutum, scutellum, anepisternum and katepisternum covered in hairs, remainder bare. Wing: membrane with a milky infusion, veins pale yellowish at base, darker brownish at apex. Costal comb with white hairs. Squama white fringed with short white hairs. Legs: femora with long hairs, denser brush­like below; tibiae with short decumbent hairs and spicules; tarsi with tarsomeres 2–4 narrowed; claws black, only gently curved; pulvilli yellowish, as long as claws. Abdomen: cordate, covered in long hairs. Genitalia (Fig., 1) similar to those of A. thornei Hesse (1938: 857) but phallosome relatively longer and the ventral lobe of the gonocoxa shorter and less directed ventrally.

Females. Very similar to males but frons broad, 2/3 width of an eye at vertex; parallel sided above, widening from just above antennae. Abdominal terga very narrowly ivory at hind margins on holotype and when partially denuded. Spermatheca terminating in a tangled coiled reservoir, pigmented brownish, similar in appearance to the spermathecae of Geron spp. ( Theodor, 1983) .

Material examined. SOUTH AFRICA: Namaqualand, Wallekraal, x.1950, Mus. Exped., Apolysis namaensis n. sp. Holotype ♀, det. A.J. Hesse (SAMC). NAMIBIA : 1♂, 2♀♀, Aurusberg/Scorpion Mine, 27°45.35’S 16°32.05’E, 15.xi.2003, F.W. & S.K. Gess, 01/04/35, from Quartinia nest in Trigonephus shell (DJGC); 2[MM], 1[F], Uguchab R., NW Aurus Mountains, 27°31.42’S 16°11.68’E, 17.ix.2003, F.W. & S.K. Gess, 03/04/43, from Quartinia nest in Trigonephus shell (AMGS).

From Hesse’s (1975) brief descriptions, A. hesseana and A. lactearia , described from females collected near Calvinia ( South Africa (Northern Cape )), are very similar to each other and possibly represent a single species. They are closely related to A. thornei Hesse (1938: 857) from South Africa (Northern & Western Cape) and identified from Namibia (Greathead, 2000) . Apolysis thornei differs in that only the abdomen is covered in dense grey tomentum and not the entire body.

The shapes of the spermathecal reservoirs of Apolysis spp. are highly diverse. They range from the tangled form found in A. hesseana to flat coils, twisted tubes, straight tubes and elongate bulb shapes ( Evenhuis, 1990). The taxonomic significance of these different shapes has not been determined but a study of the spermathecae should be included in any revisionary work on the genus in order to determine whether the shapes are of phylogenetic significance.