Keilbachia acamptochaeta, Hippa, Heikki & Vilkamaa, Pekka, 2007

Hippa, Heikki & Vilkamaa, Pekka, 2007, The flagria group of Keilbachia Mohrig (Diptera, Sciaridae) in a biodiversity hot spot: nine new sympatric species from Kambaiti, Myanmar, Zootaxa 1556, pp. 31-50 : 33-35

Keilbachia acamptochaeta sp. n.

( Figs 1 A, 3D, 5A, B, C)

Material studied. Holotype male (in NRMS). N.E. Burma ( Myanmar), Kambaiti, 7000 ft., 8.6.1934, R. Malaise. Paratype male (in NRMS). 1 male with same data as holotype but dated 12–17.6.

Male. Colour. The specimen is strongly faded because of treatment with KOH and is almost unicolorous pale yellowish-brown; the untreated wing is brownish. Head. Eye bridge Fig. 5 A: 3–4 facets wide. The face (prefrons) is laterally compressed and invaginated in both mounts and the setae are difficult to observe, but at least 4 setae can be observed. Clypeus non-setose. Maxillary palpus ( Fig. 1 A) with one palpomere, with 1 lateral seta, with or without 1 apical seta; hyaline sensilla widely scattered on dorsal surface, no sensory pit. Antennal flagellum lost in the holotype, flagellomere 4 in the paratype inflated in KOH, when non-inflated the flagellomere is apparently twice as long as broad. Thorax. Anterior pronotum with 1 seta. Episternum 1 with 1–2 setae. Wing. Length 2.23–2.46 mm. Width/length 0.40–0.41. R1/R 1.26–1.33. c/ w 0.74 –0.79. r-m and bM almost equal in length, r-m/bM 1.11, r-m with 0–1 setae, bM non-setose. Legs. Fore tibia and tarsus lost in the holotype. Apex of fore tibia, Fig. 3 D. Length of fore basitarsomere/length of fore tibia 0.77. Length of fore tibia/length of fore femur 1.55. Length of hind tibia/length of scutum+scutellum 2.02. Abdomen. Sternite 8 with ca. 30 setae, widely distributed. Hypopygium. Fig. 5 B, C: Gonocoxa with an apicomesial rounded lobelike angle. Gonostylus with 2 rather short and stout mesial megasetae arising from a common basal body, the megasetae curved, but on one side in the holotype they are unusually straight, with three additional megasetae between these and the apical tooth. Tegmen rather simple, unusually narrow. The tegmen very pale in both of the mounts and possibly partly misinterpreted.

Female unknown.

Discussion. Keilbachia acamptochaeta resembles K. flabellata in the completely one-segmented maxillary palpus, but otherwise the two species are not very similar. In K. acamptochaeta the number of the curved gonostylar megasetae is two and the setae are short, whilst in K. flabellata the number is five and they are very long; and in K. acamptochaeta there are three very strong megasetae between the curved megasetae and the apical tooth. The gonostylus of K. acamptochaeta has a strong superficial resemblance to many species of Camptochaeta , e.g. species such as C. fulvicollis (Tuomikoski) (= C. hirtula (Lengersdorf)) and C. duplicata Hippa &Vilkamaa (see e.g. Hippa & Vilkamaa 1994). It differs by the two megasetae arising from a common basal body, whilst in Camptochaeta there is only one megaseta arising from a basal body, by lacking megasetae on the lateral side of the apical tooth and by lacking a mesial flagellate seta. In Camptochaeta the number of palpomeres is always three, there is a sensory pit on the first flagellomere and the patch of setae apically on fore tibia is bordered on the proximal side.

Figures

FIGURE 1. Maxillary palpus. A, Keilbachia acamptochaeta sp. n. (paratype). B, K. flabellata sp. n. (holotype). C, K. gigas sp. n. (holotype). D, K. fasciata sp. n. (holotype). E, K. foveolata sp. n. (holotype). F, K. bicuspis sp. n. (holotype). G, K. rima sp. n. (holotype). H, K. filigera sp. n. (holotype). I, K. oligonema sp. n. (holotype). Scale 0.10 mm.

FIGURE 3. Apical part of fore tibia, prolateral view. A, Keilbachia oligonema sp. n. (Burma). B, K. fasciata sp. n. (paratype). C, K. rima sp. n. (holotype). D, K. acamptochaeta sp. n. (paratype). E, K. flabellata sp. n. (holotype). F, K. foveolata sp. n. (holotype). G, K. filigera sp. n. (holotype). H, K. bicuspis sp. n. (holotype). I, K. gigas sp. n. (holotype). Scale 0.10 mm.

FIGURE 5. Eye bridge, frontal view (A), and part of hypopygium (B, D) and gonostylus (C, E), ventral view. A, B, C, Keilbachia acamptochaeta sp. n. (holotype). D, E, K. bicuspis sp. n. (holotype). Scale 0.10 mm.