Saropogon rubriventris Wulp, 1899

Londt, Jason G. H., 1997, Afrotropical Asilidae (Diptera) 29. A review of the genus Saropogon Loew, 1847 (Dasypogoninae), ANNALS OF THE NATAL MUSEUM 38, pp. 137-157 : 151-152

Saropogon rubriventris Wulp, 1899

Figs 26-27

Saropogon rubriventris Wu 1p, 1899: 83. Wulp (1899) described this species on 'a single female from Lahej' (13°01 'N: 44° 54'E) collected by Col.]. W. Yerbury in South Yemen. The OXUM has sent me this specimen (listed below), which must be considered the holotype.

Redescription: Based on holotype 9.

Head ( Figs 26-27 ): Face brown-yellow, gold pruinose; frons, vertex and occiput dark red-brown, gold pruinose except for transverse band across vertex, including most of ocellarium, which is shiny apruinose. Setae of vertex and frons black, occiput pale yellow. Antenna pale brown-yellow; setae black; proportional lengths of segments - 1: 1.3: terminal segments missing. Width of eye: width of face ratio 0.7: 1. Mystax white; composed of ca. 25 setae arranged in 2 rows along lower facial margin. Palpus brown-yellow. Proboscis brown-yellow proximally. red-brown distally, straight.

Thorax: Mesonotum red-brown, darker mid-dorsally, postpronotal and postalar lobes brown; strongly gold pruinose. Macrosetae yellow-white: 2-3 npl; 3-4 spal; 2 pal; ca. 3-4 pairs dc postsuturally; pronotal lobes lacking macrosetae. Scutellum brown; 2 pale yellow marginal macrosetae; disc asetose, gold pruinose. Pleura brown-orange with darker red-brown patches, gold pruinose; katatergite with ca. 13 scattered yellowish setae. Wing: 7.7 x 2.8 mm; cell m3 and cup open; membrane unstained, transparent; microtrichia absent except at tip and along margins. Halter: Yellowbrown. Legs: Uniform brown-yellow, tarsi slightly darker; setlle yellow and dark redbrown, the latter mostly on tarsi.

Abdomen: Terga red-yellow, sterna brown-yellow, T 1 red-brown anteriorly, T2-T7 with anterolateral dark red-brown spots, hind margins of T2 and T3 silver pruinose; macrosetae pale yellow, confined to lateral parts of Tl.

Material examined: Type ( OXUM): SOUTH YEMEN: 1 ♀ holotype, 'Type / v.d. Wulp / Trans. Ent. Soc. / 1899, page 83-4'; ' So W. Arabia / 15 miles N. W. of / Aden, Lahej / Capt. Mar. 10.95 [1895] / & pres. 1899 by / 1. W. Yerbury'; '1899 / 7689 '; 'Type Dip: 180 / Saropogon / rubriventris / van der Wulp / Hope Dept. Oxford' .

Relationships: Wulp compared the species with S. vestitus Wiedemann , saying it differed only in the closed condition of the fourth posterior wing cell (i.e. m3). Efflatoun (1937) states that both open and closed character states are found in vestitus , suggesting that rubriventris is probably a synonym of vestitus . The situation is further complicated by the fact that the unique rubriventris holotype was collected at the same locality recorded for incisuratus , although 18 days earlier. It is, therefore, possible that this female may be that of incisuratus , which is known only on males. If this is true, incisuratus demonstrates far greater sexual dimorphism than appears to be found in any other species known to me. Sexual dimorphism may, however, also occur in vestitus , as this species is also known only on females (Note: Theodor (1980) mentions the possibility that S. aegyptius may represent the male). Yet another possibility exists, and that is that jugulum (Loew, 1847) could be the male of rubriventris (? = vestitus ) as Efflatoun (1937) reports numerous males having been obtained at many localities at which vestitus females were found. Quite clearly these issues need to be resolved before taxonomic stability can be achieved. For the present I retain the status quo for the afrotropical taxa, pending modem revision of the palaearctic fauna.

Figures

Figs 26--27. Saropogon rubriventris Wulp. Head, holotype (Lahej). 26. Lateral. 27. Anterior. Scale line equals 1 mm.