Chalastonepsia nigricoxa, Ševčík & Hippa, 2010

Ševčík, Jan & Hippa, Heikki, 2010, New species of Chalastonepsia and Pectinepsia gen. nov. (Diptera: Mycetophilidae) from the Oriental and Australasian Regions, Acta Entomologica Musei Nationalis Pragae 50 (2), pp. 595-608 : 601

Chalastonepsia nigricoxa sp. nov.

( Figs. 1, 2 , 8–11 )

Type material. HOLOTYPE: J, N.W. THAILAND: CHIANG MAI PROVINCE: Doi Pha Hom Pok , 2000 m, N 20 7.644 E 99 8.89, Malaise trap, 24.–30.vii.2006, leg. M.V.L. Barclay & H. Mendel, BMNH (E) 2006-128 ( BMNH). PARA- TYPE: J, the same data as holotype ( JSOC).

Description. Male. Body length 4.1 mm. Head yellowish, vertex and occiput covered with dark setae. Small dark brown patch around each ocellus. Three ocelli, almost in one line. Lateral ocellus larger than the median one, the former separated from the eye margin for a distance of about its diameter. Antenna pectinate. Scape and pedicel yellowish, slightly prolonged backwards. Flagellum mostly yellow, flagellar projections apically darker. Flagellomeres 1 to 8 with an anterior projection, at most as long as the height of head, covered by thin setae about as long as the diameter of the projection. The apical six flagellomeres without such projection, only flagellomere 9 with a short anteroapical one, not longer than its diameter, and flagellomeres 10 to 12 with even shorter ones. Mouthparts much reduced, palpus with only one visible palpomere. Thorax. Mesonotum yellowish, with front, lateral and hind margins dark brown. Scutum covered by dark setae, with thin bare longitudinal stripes. Scutellum all dark brown, with a row of short apical setae. Mediotergite and most lateral sclerites dark brown and bare. Laterotergite all dark brown, with dark setae on its ventroposterior two thirds. Anepimeron, preepisternum 2 and anepisternum dark brown, the latter with its posterior half yellow. Proepisternum and antepronotum yellow, with several short setae. Haltere brownish yellow. Wing hyaline, unmarked, membrane covered only with microtrichia, without macrotrichia. Wing length 3.7 mm. Costa produced beyond R5 to one third of the distance between the tips of R5 and M1. Sc short, bare, ending in R1 well before base of ta. Crossvein ta thrice as long as Rs. The stem of M-fork short, as long as ta. Base of Cu-fork before the base of M-fork. CuP weak, shorter than A1. Legs covered with dark trichia and setae. All coxae dark brown, femora yellow. Tibiae brownish yellow, without strong bristles. The apex of the fore tibia without distinct tibial organ. Mid tibia without sensory organ. Abdomen mostly dark brown. Tergite 1 all yellow, tergites 2 to 6 with front margins yellow. Terminalia ( Figs 8.–11 ). Tergite 9 subrectangular, 0.6 times as long as broad and about twice as long as tergite 8, caudally with medial protuberance covered by thick black setae. Cerci almost as long as tergite 9, hidden behind it. Sternite 8 narrow, as long as tergite 8 but 3–4 times shorter than sternite 7. Gonocoxites completely fused, caudal margin with a distinct medial protuberance. Gonostylus subrectangular, about half as long as gonocoxite, with a comb of black setae apically.

Female. Unknown.

Differential diagnosis. This new species closely resembles C. montana sp. nov. but differs mainly in the following characters: apical six flagellomeres without long projection, projections on flagellomeres 1 to 8 shorter and apically darkened, different colour pattern of thorax and abdomen (see Figs. 1 and 3 ), dark coxae and details on the male terminalia (e.g. apical dark setae on gonostylus slightly bent, posterior margin of T9 more straight with medial protuberance less distinct).

Etymology. The name is a Latin noun in apposition, nigricoxa , black-coxa, referring to the colour of coxae.

Distribution. Thailand (Chiang Mai province).

Figures

Figs. 1–3. 1–2 – Chalastonepsia nigricoxa sp. nov. (paratype) (1 – habitus; 2 – head from below). 3 – C. montana sp. nov. (paratype), head and thorax.

Figs. 8–9. Chalastonepsia nigricoxa sp. nov. (holotype). 8 – male terminalia, dorsal view (tergite 9 and cerci removed); 9 – same, ventral view. Scale bar: 0.1 mm.