Daspletis Loew, 1858

Londt, Jason G. H., 1983, The Genus Daspletis Loew, 1858 And The Description Of Two New Genera, Anasillomos And Remotomyia (Diptera: Asilidae: Stenopogoninae), Journal of the Entomological Society of Southern Africa 46 (2), pp. 283-308 : 285-288

Daspletis Loew

Daspletis Loew, 1858: 337 . Type species D. vulpes Loew, 1858: 337 , by monotypy.

Neodysmachus Ricardo, 1925: 263 . Type species N.: setithoracicus Ricardo, 192 5 : 264, by original designation. Syn. nov.

Ricardo (19 5) erected the genus Neodysmachus for one Cape species of Daspšetis-like flies which possess an open rs cell. This is insufficient groundso n which to base a genus. Venation can be highly variable and the open or closed condition of wing cells may not be an entirely reliable feature. In. hermanni, for example, rf, may be open, closed on the wing margin, or closed and with a stalk-vein joining the cell to the wing margin. I consider Neodysmachus a synonym of Daspletis .

The separation of Daspletis and Microstylum is in some ways far more problematic as these genera share so many features. Both Hull (196) and Oldroyd 1974) use the character ‘ first posterior cell open’ to characterize Microslylum in their keys. My preliminary observations on this genus indicate that the closed condition also exists, especially in species of the M. acutirostrae group. The genus Eclipsis Bezzi was listed as a valid genus by Oldroyd (1980) in the Afrotropical Catalogue even though Papavero (1973) had placed it as a 'subgenus' of Microstylum . The only described species of Eclipsis, E. maculiventris Bezzi , possesses a closed rs cell and is quite clearly related to M. acutirostrae and related species (some of which remain undescribed). It is obvious that this characteristic is unreliable. The strongly arched M; vein frequently used to characterize Microsgylum is also unsatisfactory as there are some instances where it is difficult to decide if the vein is ‘ strongly’ arched or not. For the present I am relying on three other features, which appear to be common to all described species of Afrotropical Microsçylaém, to separate this genus from Daspletis . The facial protuberance of Daspletis occupies at least three-quarters of the face while in Microsçvlum this swelling is confined to the lower half of the face and often only to a small area just above the lower facial margin. Daspletis species are more bristly; the dorsocentrals extend from the posterior to the anterior margins of the mesonotom, whereas in Micraslylum they are well developed only posterior of the transverse suture (there may be one or two small ones anterior of the suture but they are never found near the anterior margin of the mesonotum); the postmetacoxal membrane is covered with long setae in all Daspfetís while this membrane is bare in most Micrasÿlaem. The reliability of these features is not known with any certainty at present but I intend revising Microstyšam at a future date and this matter will be attended to then.

Daspletis appears to be active in late summer ( Table 1 ); the exceptions being hermanni (which is active in spring) and setithoracicus (active from October-May).

Tables

TABLE 1. Seasonal incidence of species in the stenopogonine genera covered in this paper.

SPECIES						MONTHS
	j	F	M	A	M	J	J	A	s	o	N	D
Aııaıillama: chgisapns		o						o		o
Daxpletís bananas'									o	o
D. ftífåuí		O	O								Q
D. pšacadz:		O		O								o
D.:etithoracim	O				o					o	o	o
D. stmaufa			o
D. vuípes			o		o
Dioctobromafiavotenninzztum				O
Dogonía nigra			o
D .. raegerí			o
Oratosgëšam ¡ øpidum		o						o	o	o
Rzmotomjia albasetamr			O					o
R. brunales									o
R. longipaipxıs									o
R. pmritkaz								o	o	o