Achalcus micromorphoides, 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 : 44

ACHALCUS MICROMORPHOIDES SP. NOV. ( FIG. 8 )

Male. Small, compact species. Head. Face dark brown, 1.5¥ as wide as ocellus; with epistoma bare and clypeus with dense white pubescence. Frons dark brown. Occiput convex ventrally, distinctly concave dorsally, dark brown, slightly dusted. Uppermost postocular bristles black, lower brown. Palp rather large (1/5 of eye), circular, dark brown. Antenna entirely black with first flagellomere short, ovate triangular, 1.6¥ as long as deep and 1.3¥ as long as scape and pedicel combined. Arista 1.6¥ as long as first three joints of antenna, distinctly subapical, with microscopic pubescence.

Thorax blackish brown on dorsum of mesonotum and scutellum, dark brown on pleura, postnotum and metapleura. Postnotum with black frontolateral triangle. Five ac, less than 1.5¥ as long distance between rows. Sutural bristle absent.

Abdomen blackish brown, shining, conical. Genital capsule concolorous, moderately developed. Hypopygium. Aedeagus long, with slight subapical dorsal bend; all epandrial setae inserted near apex of epandrial lobe ( Fig. 8A ); ventral bristle of surstylus simple; VEP and DEP evident; postgonites pale but evident; cercus fairly small, triangular with fairly short marginal bristles ( Fig. 8B ).

Wing. Halter distinctly infuscated. Wing pale, with R 4+5 hardly curved, R 4+5 and M 1+2 practically parallel. Proximal section of vein CuA 1 2.1¥ as long as apical section; CuAx ratio 1.9. Wing length 1.8 mm.

Legs mainly obscure (brownish) yellow with brown coxae; only coxa I dark brown, yellowish laterally. Trochanters brownish yellow. Femur I brownish yellow, femur II and III dark yellow; femur I without erect ventral bristle and with one strong pv preapical bristle. Femur II with one strong ad, one small av and one strong pv preapical bristles. Femur III with one strong ad and one strong av preapical bristles. Tibia I and III brownish yellow, tibia II yellow; tibia I with two dorsal bristles at basal 1/3 and 2/3; tibia II with two very strong (1/5 of tibial length) ad and one strong pd bristles, basal bristles forming adpd couple; tibia III with three very strong ad, three very strong pd bristles and four ventral setae. Tarsus I and II brownish yellow with 5th tarsomere dark; tarsus III with 1st and 2nd tarsomeres dark yellow, from 3rd onwards entirely dark. First tarsomere of leg III 0.8¥ as long as 2nd tarsomere. Body length 1.5 mm.

Female. Unknown.

Etymology. Refers to the stout and small Micromorphus -like habitus of this species.

Holotype. 1♂, CHILE: Region de Coquimbo, Prov. Elqui, Coquimbo, Huaquen , 26.vii.1960 (L. Peña) ( CNC; D, hypopygium mounted).

Figures

Figure 8. Achalcus micromorphoides sp. nov. (male). A, epandrial lobe; B, hypopygium.