Meuffelsia erasmusorum Grichanov, 2008

Grichanov, Igor Ya. & Mostovski, Mike B., 2008, Meuffelsia, a new genus of long-legged flies from South Africa, with a key to Afrotropical peloropeodine and allied genera (Diptera: Dolichopodidae), African Invertebrates 49 (2), pp. 159-159 : 161-164

Meuffelsia erasmusorum Grichanov , sp. n.

Figs 1–6

Etymology: The species is named in honour of Thea and Cobus Erasmus, on whose property the types were collected.

Description:

Colour (dry paratypes): Frons and face weakly shining bronze, brownish pollinose. Palpus and proboscis blackish brown; thorax bluish black; legs with coxae, femora and tarsi from apex of basitarsus mainly light brown; other podomeres mainly reddish yellow; abdomen black with brown sternites.

Male.

Head: Frons and face with black ground colour. One strong but short postvertical seta positioned far from postocular setal row; postocular setae all dark; 1 or 2 upper and 1 lower setae slightly longer than the others. Face under antennae 2× as wide as height of postpedicel. Antenna black, slightly longer than head height. Scape small, vase-like, with projecting inner angle forming distal denticle; pedicel larger, globular, with ring of short setulae and elongate apicodorsal seta; postpedicel subtriangular, as long as high at base, densely haired; stylus inserted dorsally at 2/3 from postpedicel base, 2× as long as main segments of antenna combined, shortly pubescent, with short thick segment 1 and filiform segment 2. Ratio of lengths of scape to pedicel to postpedicel to stylomere 1 to stylomere 2, 3:3:4:1:20. Palpus and proboscis yellow-brown, palpus subtriangular, with dark pubescence and dark short bristle.

Thorax: With dark bristles, mesonotum blackish brown, pleura dark brown. One long and 1 short intra-alar, 1 humeral, 1 supra-alar, 2 notopleurals, 1 sutural, 1 presutural; 6 (2+4) dorsocentrals, with first slightly shorter and last slightly longer than others; 5th seta not shifted towards lateral margin; 6 or 7 pairs of biserial acrostichals extending to well-developed posterior mesonotal flattening. Upper propleuron without setae; proepisternum with 1 strong seta and 1 short hair above fore coxa.

Legs: Mainly dirty yellow; mid and hind coxae, hind femur and apical segments of all tarsi distinctly brownish. Fore and mid coxae with dark anterior and apical cilia; hind coxa with 1 black bristle at middle. Fore leg without extraordinary setae; fore femur with just 1 or 2 short posteroventrals at apex; fore tibia simple, without strong setae; fore tarsus simple, with ordinary setulae. Length ratio of fore femur to tibia to tarsus (segments from first to fifth), 19:23:10:4:3:3:4. Mid femur simple, bearing 1 strong anterior subapical bristle and 1 fine posteroventral seta; mid tibia simple, with 1 very strong anterodorsal and 1 fine posterodorsal setae at basal third and 3 apical setae; no ventral setae; mid tarsus simple; segments 1–4 each with circlet of short apical spinules. Length ratio of mid femur to tibia to tarsus (segments from first to fifth), 30:31:14:5:4:3:4. Hind femur with 1 strong anterior subapical seta; hind tibia simple, with 1 strong anterior at basal 1/3, and 3 short posterodorsal, 2 or 3 very short ventral, 3 simple short apical setae, with only anterior apical seta somewhat longer, without strong dorsal subapical seta; hind tarsus simple; hind basitarsus with 1 short basoventral and 1 or 2 short apicoventral setae, with very small basal tooth posteriorly directed towards apex of hind tibia. Length ratio of hind femur to tibia to tarsus (segments from first to fifth), 35:35:15:14:6:4:5.

Wing: Entirely greyish, veins brown. Costa simple, with simple costal setulae reaching R 2+3. Ratio of part of costa between R 2+3 and R 4+5 to that between R 4+5 and M 1+2, 18:12. R 2+3, R 4+5 and M 1+2 practically straight; R 2+3 and R 4+5 slightly diverging towards wing apex; R 4+5 and M 1+2 parallel in distal half. Ratio of apical to basal part of M 1+2, 70:27. Ratio of m–cu to apical part of CuA 1, 6:32. Crossvein m–cu somewhat weaker than adjacent longitudinal veins,forming right angles with M 1+2 and CuA 1.Anal vein distinct,short; anal lobe developed, narrow. Lower calypter small, brownish, with short dark cilia. Haltere brown.

Abdomen: Dark brown, with black hairs and marginal setae, cylindrical; sternites 2–4 large, light brown; sternites 5 and 6 small. Segment 7 short, with tergum broad and sternum reduced; segment 8 brown, large, covering about half of left lateral surface of epandrium, bearing numerous short cilia; epandrium brown, globular, asymmetrical, slightly longer than high, as wide as high, longer than tergite 5; hypopygium with rounded-ovate, densely haired cercus; hypandrium concealed, with large triangular lobe on right side at 2/3 of its length; aedeagus with small ventral subapical excavation and short thin process before excavation; ventral surface of epandrium bare; distal epandrial lobes asymmetrical, short and broad, bare, without projections; surstyli asymmetrical, with left dorsal arm half the length of right one, both broad, bearing a few short setae, and ventral arms of surstyli subequal in length, thin, directed ventrad, bearing a few short setae at apex.

Measurements (mm): Body length 1.7, antenna length 0.4, wing length 1.65, wing width 0.65, hypopygium length 0.4.

Female.

Similar to male except lacking male secondary sexual characters; each hemitergite arcuate, narrow, with four short black setae (acanthophorites); cercus short, widened distad; anal plate broad, wider than long.

Measurements (mm): Body length 1.2–1.3, antenna length 0.35, wing length 1.5, wing width 0.55.

Holotype (in glycerol): ơ SOUTH AFRICA: KwaZulu-Natal: Louwsburg, Sanyati Farm , 27°34'00"S: 31°17'57"E, alt. 1090 m, 18.xii.2005 – 6.ii.2006, Malaise trap, M. Mostovski.

Paratypes: SOUTH AFRICA: KwaZulu-Natal: ^same data as holotype, but apparently teneral, with lightened and shrunken body; ơ (in glycerol) ^(on pin) Clifton Canyon, Gillitts, nr Hillcrest , 2930 Dd , 17.x.1976, R. M. Miller & P. Stabbins .

Habitat: The type specimens from Sanyati Nature Farm were collected in the primarily indigenous riverine bush ( Fig. 7 ). The surrounding vegetation includes Magic guarri ( Euclea divinorum ), Thorny elm ( Chaetachme aristata ), Flame thorn acacia (Acacia ataxacantha), Wild mulberry ( Trimeria grandifolia ), Pink dombeya (Dombeya burgessiae), Lemon thorn ( Cassinopsis ilicifolia ), Broom-cluster fig ( Ficus sur ), Waterberry ( Syzygium cordatum ), Horsewood ( Clausena anisata ), Thorny rope ( Dalbergia armata ), Climbing flatbean ( Dalbergia obovata ), Bladdernut ( Diospyros whyteana ), Silky fibre-bush ( Englerodaphne pilosa ), False assegaai ( Maesa lanceolata ), Rhus spp. , Silkybark ( Maytenus acuminata ), Turkeyberry ( Canthium inerme ), Wild pomegranate ( Burchellia bubalina ), Tree fuchsia ( Halleria lucida ), Zulu spurflower ( Plectranthus zuluensis ), Traveller’s joy ( Clematis brachiata ), Wild iris ( Dietes iridiodes ), and Wild impatiens ( Impatiens hochstetteri ). Temperatures ranged between 16–32°C during Dec. 2005 – Jan. 2006, and the precipitation was about 350 mm.

As reported by Dr R. M. Miller, the collecting site of the other two paratypes was most probably along the small river that runs down the valley with indigenous forest .

Figures

Fig. 1. Meuffelsia erasmusorum Grichanov, sp. n., general habitus of the holotype in alcohol before dissection.

Figs 2–6. Details of Meuffelsia erasmusorum Grichanov, sp. n.: (2) antenna; (3) wing; (4) oviscapt, dorsal aspect; (5, 6) hypopygium, left and right lateral aspects. Scale bars: 0.5 mm in Fig. 3, otherwise 0.1 mm.

Fig. 7. Habitat at Sanyati Farm where the holotype and one of the paratypes of M. erasmusorum sp. n. were collected. (Photo courtesy Th. & C. Erasmus.)