Achalcus maculipennis, 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 : 41-44

ACHALCUS MACULIPENNIS SP. NOV. ( FIG. 7 )

Male. Small, rather slender species. Head. Face dark brown, not as wide as ocellus, eyes almost touching above clypeus. Frons very large and broad, shining blue. Occiput rather flat with central dorsal furrow, dark brown, shining. Postocular bristles yellow, uppermost slightly darker. Palp large (about 1/4 of eye), ovoid triangular, pale yellow, reddish at apex; with pale pubescence, and one pale apical bristle. Antenna reddish yellow with scape slightly infuscated dorsally and first flagellomere brown on dorsal 1/3; latter ovoid triangular, 1.3¥ as long as deep and 1.7¥ as long as scape and pedicel combined. Arista 2.9¥ as long as first three joints of antenna, inserted apically, with 1st segment darker and 2nd white; with short pubescence ( Fig. 7B ).

Thorax pale reddish yellow with brown central area on dorsum between dc rows until scutellum. Upper half of pleura darker. Postnotum large, with small black frontolateral triangle. Lower half of metapleura pale reddish yellow, upper half pale brown. Three ac, 1.5¥ as long as distance between rows. Five dc, with 1st dc small. One rather small sutural bristle present.

Abdomen with tergites including genital capsule brown. Sternites yellowish white, with yellowish pubescence. Hypopygium. Aedeagus mainly pale, rather long with subapical dorsal bend; ventral bristle of surstylus simple; VEP and DEP evident; postgonites large and dark; cercus small, short triangular ( Fig. 7C ).

Wing. Halter brown. Wing pale with two distinct spots at wing centre and apex, with R 4+5 and M 1+2 diverging, R 4+5 slightly sinuous. Proximal section of vein CuA 1 3.2¥ as long as apical section; CuAx ratio 1.6. Wing length 1.6 mm ( Fig. 7A ).

Legs including trochanters mainly pale yellow with darker coxae; with brownish pubescence and bristles. Coxae brownish yellow with coxa I darker especially on outer face. Femur I without erect basoventral bristle and with two pv preapical bristles. Femur II with

B

one strong ad, one indistinct av and one strong pv preapical bristles. Femur III with one strong ad, inserted in lower half, and one strong av preapical bristles. Tibia I without dorsal bristles; tibia II with two strong thin (> 2 ¥ tibial depth) ad and one moderate pd bristles, ad bristles inserted at basal 1/4 and 2/3; tibia III with three moderate ad and three moderate pd bristles; with two true av bristles on apical half and several erect pv setae. All tarsi yellow with 5th tarsomeres darker, only slightly darker in leg I and II. First tarsomere of leg III 0.7¥ as long as 2nd tarsomere.

Female As in male, except for the following: palp 2/5 of eye, rectangular, brownish at apex with two apical bristles. Antenna with 1st flagellomere as long as deep; arista entirely white. Thorax pale reddish yellow with only notopleura brownish; one ac. Abdomen with six pubescent segments with sternites 2–5 brownish yellow and sternite six brown; 8th segment reddish brown with eight stout dark dornen; cercus dark. Halter pale; proximal section of vein CuA 1 2.6¥ as long as apical section; CuAx ratio 2.1. Legs including coxae entirely pale yellow. Body length 1.7 mm, wing length 1.6 mm.

Etymology. Refers to the maculated wing in both male and female specimens of this species.

Holotype. 1♂, PERU: Monson Valley , Tingo Maria, 9.xii.1954 (Schlinger & Ross) ( CAS; D, hypopygium, antenna and wing mounted).

Allotype. 1♀, same data.

Paratypes. ECUADOR: 1♀, Napo Province, approx. 1 km N. Napo River, E. of Coca Orellana, Sacha Lodge , 0.5S 76.5 W (edge of old growth forest), 270 m, 3– 13.vii.1994, MT (Hibbs Kerr) ( POLLET, W) .

Figures

Figure 7. Achalcus maculipennis sp. nov. (male). A, wing; B, antenna; C, hypopgyium.