Australachalcus cummingi, Pollet, 2005

Pollet, Marc, 2005, Systematic revision of Neotropical Achalcus and a related new genus (Diptera: Dolichopodidae, Achalcinae) with comments on their phylogeny, ecology and zoogeography, Zoological Journal of the Linnean Society 143 (1), pp. 27-73 : 56

AUSTRALACHALCUS CUMMINGI SP. NOV. ( FIG. 17 )

Male. Rather small, slender species. Head. Face dark brown, heavily dusted, as wide as ocellus. Frons dark brown. Occiput distinctly concave dorsally, dark brown. All postocular bristles dark. Palp small (1/6 of eye), ovoid, dark brown. Antenna with scape and pedicel yellow, slightly infuscated dorsally; first flagellomere entirely dark brown, elongate triangular, about 2¥ as long as deep and 1.6¥ as long as scape and pedicel combined. Arista 0.8¥ as long as first three joints of antenna, distinctly subapical, practically bare.

Thorax. Mesonotum including pleura shining brown with greyish lines along ac and dc; humeri and notopleura yellowish brown with scutellum brown with yellowish lateral corners. Postnotum slightly paler than pleura, with distinct triangular black frontolateral margin. Metapleura entirely dark brown. nine ac, less than 1.5¥ as long as distance between rows. One small sutural bristle present. About three small bristles present between dc 1–2, ps and sutural bristles.

Abdomen with first three abdominal tergites yellowish brown with dark caudal edge, from posterior half of 4th onwards (including genital capsule) blackish brown; with strong marginal bristles. Sternites greyish brown. Hypopygium with simple hypandrium with raised apical rim; aedeagus dark, straight and slen- der; ventral bristle of surstylus with apical flag; VEP and DEP evident; postgonites robust and dark; cercus large, lamelliformous, with strong apical and dorsal bristles ( Fig. 17 ).

Wing. Halter and wing pale, latter with R 4+5 slightly curved; R 4+5 and M 1+2 nearly converging at apex. Proximal section of vein CuA 1 1.3¥ as long as apical section; CuAx ratio 2.6 x. Wing length 2.6–2.7 mm (n = 2).

Legs including coxae and trochanters mainly pale yellow, with leg III darker. Femur I with erect ventral bristle at basal 1/4, longer than femur is deep, basad of row of erect av bristles, decreasing in length towards apex; two most basal av bristles distinctly longer than apical ones; with two pv preapical bristles. Femur II with 1–2 very strong (about 1.5¥ femur depth) erect av bristles at extreme base, followed by short inclined setae until apex; with one strong ad and one av preapical bristles. Femur III dark yellow, slightly infuscated dorsally, with one row of inclined equal-sized rather strong (1/2–1/3 of femur depth) av bristles; with one moderately strong ad, inserted in lower 1/3, and one av preapical bristles. Tibia I without dorsal bristles; tibia II with one rather small (1/9 of tibial length) ad and one rather small pd bristles; basal bristles inserted at basal 1/3, forming ad-pd couple; with multiple ventral rows of short spine-like bristles on apical 2/3; tibia III brownish yellow, slightly swollen towards apex, with two small ad and three small pd bristles; with dense pubescence and distinct ventral setae. All tarsi with 5th tarsomere dark; tarsus I pale yellow, from 2nd tarsomere gradually darkened, slightly dorsoventrally flattened; tarsus II dark yellow, gradually darkened; tarsus III entirely brown. First tarsomere of leg III as long as 2nd tarsomere.

Female. Unknown.

Etymology. Species named in honour of Jeffrey Cumming (Invertebrate Biodiversity, Agriculture and Agri- Food Canada, Ottawa), who supported my study of the Chilean achalcine specimens from the CNC.

Holotype. 1♂, CHILE: Region de la Araucania, Prov. Malleco, Gualletue , 1200 m, 9–14.xii.1963 (L. Peña) ( CNC; D, hypopygium mounted).

Paratypes. CHILE: 1♂, Region del Maule, Prov. Curicó, Curicó, El Coigual, 20–26.i.1964 (L. Peña) ( CNC; D, lacking hypopygium) .

Figures

Figure 17. Australachalcus cummingi sp. nov. (male). Hypopygium.