Anthomyia acutula, Ackland, 2001

Ackland, D. M., 2001, Revision of afrotropical Anthomyia Meigen, 1803 (Diptera: Anthomyiidae), with descriptions of ten new species, African Invertebrates 42, pp. 1-94 : 84-86

Anthomyia acutula sp. n.

( Figs 163 , 200–208 )

Holotype Ò: SOUTH AFRICA: Western Cape: ‘ SOUTH AFRICA (S24) / C. P. [Cape Province] Dwyka R. / Merweville-Koup Rd / 2.i.1972 ’ [white rectangular printed label]; ‘Southern / African Expd. / B. M. 1972–1’ [white rectangular printed label]; ‘Holotype’ [white circular label with red perimeter] ; ‘ HOLOTYPE Ò / Anthomyia acutula / D. M. Ackland’ [red rectangular printed and written label]. Genitalia dissected and mounted in plastic tube in glycerol on staging pin. In good condition. In BMNH.

Paratypes: KENYA: 2Ò, Muguga , ix.1969, C. F. Dewhurst ( BMNH) . NAMIBIA: 1Ò, (W52), Swakop R., 3 mls S Okahanja , 7.iv.1972, Southern African Expd. B. M. ( BMNH) ; NAMIBIA: 6Ò2^, Windhoek, SE 2217 Ca , 20.xi.–5.xii.1973, Malaise trap, H15789 ( NMWN) ; 1Ò, Windhoek , 22º34'S: 17º05'E, 11.xii.1986, J. Irish, Malaise trap (all NMWN type series T635 ) . SOUTH AFRICA: Gauteng: 1Ò, Johannsburg, Parktown North , 1.ii.1930, B. de Meillon ( BMNH) ; 1Ò, Teakworth , 19.iv.1954, F. Zumpt ( BMNH) . Free State: 2Ò, Viljoenskroom , 3.iv.1955, F. Zumpt ( BMNH) . Western Cape: 1Ò4^, Karoo National Park , 15 km N Beaufort West, 12.xi.1986, 3222 AB, Londt & Quickelberg, dry Acacia woodland ( NMSA) .

Etymology: L. acutulus = rather subtle. Refers to the subtle characters defining the species.

Male: Differs from subabyssinica as follows: 5th sternite ( Figs 203–205 ) with setae on inner margins of processes longer, those closest to median line equally as long as the others; processes in profile ( Figs 204, 205 ) with the membranous lobes larger and more projecting ventrally, with the distal margin concave, or at right angles to the process; postgonite ( Fig. 206 ) with the excavation apically on the ventral margin (beyond the small setula) smaller and less deep, hence apical finger-like extension shorter. Central processs of synsternite (6+7) ( Fig. 208 ) larger, divided to base into two leaflike processes which are expanded apically when viewed in profile (not flat).

Female: Not distinguished with certainty from females of subabyssinica . The females listed as paratypes of acutula were all collected with males at the same time and place, and no males of subabyssinica were caught. The cerci of a female paratype from Namibia ( Fig. 163 ) bears more robust setae, and the anterior sclerotised arms of tergite 8 are straight compared to subabyssinica ( Fig. 162 ).

Discussion: A. acutula can generally be recognised without dissection by the larger membranous lobes on the processes of the 5th sternite. The distal margin (in lateral view) is generally rather ragged (often concave). A. subornata has a similar (slightly smaller) membranous lobe, but has a small dorsal projection on the distal section of the aedeagus, which is absent in acutula . In acutula also the pregonite is longer than wide, and the postgonite at the point of insertion of the seta on the ventro-apical margin is more or less obtuse, whilst in subornata the margin distal to the seta is strongly incised. There is no information on the life history. The specimens from the Karoo National Park were caught in a dry Acacia woodland.

Distribution: Only known from Kenya, Namibia and South Africa.

Figures

Figs 161–163. Apical segments of ^ ovipositors. 161. Anthomyia abyssinica Jaennicke (Kenya). 162 Anthomyia subabyssinica sp. n. (KwaZulu-Natal, South Africa). 163. Anthomyia acutula sp. n. (Namibia).

Figs 200–208. Anthomyia acutula sp. n. holotype Ò. 200. Thorax, dorsal view. 201–208. Terminalia. 201. Cercal plate and surstyli, caudal view. 202. Ditto, lateral view. 203. 4th and 5th sternites, ventral view. 204. 5th sternite, lateral view. 205. Ditto. 206. Gonites. 207. Distal section of aedeagus. 208. Central process of synsternite (6+7).