Campsicnemus tahaanus Evenhuis

Evenhuis, Neal L., 2008, The Campsicnemus lobatus and zigzag groups in the Society Islands, French Polynesia (Diptera: Dolichopodidae), Zootaxa 1910, pp. 27-44 : 42

Campsicnemus tahaanus Evenhuis , new species

( Figs. 17 , 22 )

Diagnosis. This species is easily distinguished from the other members of the zigzag group by the single bifid seta ( Fig. 17 ) on the ventroapical third of the male mid femur (this modified seta hooked, curlicue, kinked, or zigzagged in the other species of this group).

Description. Male. Body length: 1.5 mm. Wing length: 1.4 mm. Head (damaged: the eyes, face, front and antennae are missing). Occiput and vertex black with blue highlights; palp small, dark brown; proboscis brown, extending below level of eye in lateral view.

Thorax: Mesoscutum (cracked medially and slightly damaged with some setae missing but setal sockets visible to allow for setal counts), scutellum, and pleura dark brown to black throughout, with a few metallic greenish highlights laterally; thoracic setae black: 1 + 3 dc; 2 np; 2 ph; 1 pa; 1 + 1 sc; ac absent; halter stem and knob brown.

Legs: CI and FI white; CII and CIII brown; FII yellowish brown, FIII yellowish brown basally, becoming darker brown on apical one-eighth; remainder of legs yellowish brown; FI and remainder of foreleg unmodified, without MSSC; FII ( Fig. 17 ) with 5 stiff setae ventrally, single thick straight seta and single bifid seta on apical third of ventral surface; TiII ( Fig. 22 ) relatively straight, with long setae restricted to apical one-fourth (MSSC), smaller black setae and hairs along entire ventral surface. Remainder of leg segments without MSSC.

Wing: Pale smoky throughout; subcostal section straight, not concave; alula extremely reduced; no indentation on M1+2 beyond crossvein dm-cu; crossvein dm-cu perpendicular to CuA1.

Abdomen. Brown with short black hairs dorsally on each tergite, a few longer hairs laterally; tergal interstices whitish; sternites brown. Hypopygium brown with paler brown cerci, not dissected.

Female. Unknown.

Types. Holotype ɗ (BPBM 16,654) [BPBM 101302] from FRENCH POLYNESIA: Society Is: TAHAA: Vaihururu Stream, 350 ft, 16.61365°S, 151.48914°W, riffles/pools, 21 Jun 2007, R. Englund, L. Englund.

Etymology. The species epithet derives from the type locality of the island of Tahaa.

Figures

FIGURES 14 – 18. Campsicnemus zigzag group male mid femur. 14. C. mylloseta; 15. C. ogradyi; 16. C. ostlinx; 17. C. tahaanus; 18. C. zigzag.

FIGURES 19 – 23. Campsicnemus zigzag group male mid tibia. 19. C. mylloseta; 20. C. ogradyi; 21. C. ostlinx; 22. C. tahaanus; 23. C. zigzag.