Keilbachia foveolata, 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 : 43

Keilbachia foveolata sp. n.

( Figs 1 E, 3F, 4B, 8B, C, D)

Material studied. Holotype male (in NRMS). N.E. Burma ( Myanmar), Kambaiti, 7000 ft., 4.4.1934, R. Malaise.

Male. Colour. The single specimen is strongly faded, almost unicolorous pale yellowish-brown. Head. Eye bridge, Fig. 8 B, 3 facets wide, medially with a gap of two facets width. Face (prefrons) with 7 setae. Clypeus non-setose. Maxillary palpus ( Fig. 1 E) with 2 palpomeres. Palpomere 1 with 1 seta, with many hyaline sensilla scattered on the dorsal surface, without sensory pit. Palpomere 2 with 4 setae. Antennal flagellomeres rather inflated in KOH and not drawn, flagellomere 4, in a non-inflated condition, apparently twice as long as broad. Thorax. Anterior pronotum with 1 seta. Episternum 1 with 5 setae. Wing ( Fig. 4 B). Length 2.75 mm. Width/length 0.41. R1/R 0.98. c/ w 0.64. r-m and bM nearly equally long, r-m/bM 1.08, r-m with 1 seta very close to Rs, bM non-setose. Legs. Apex of fore tibia, Fig. 3 F. Length of fore basitarsomere/ length of fore tibia ca. 0.72. Length of fore tibia/length of fore femur ca. 1.60. Length of hind tibia/length of scutum+scutellum ca 2.26. Abdomen. Sternite 8 visible in lateral view and the setae difficult to count, with ca. 20 setae, in two transverse rows on posterior half. Hypopygium. Fig. 8 C, D: Gonostylus with 2–3 long curved mesial megasetae arising from a common basal body; whether the number of these megasetae really is two on the left side in the holotype is uncertain because the number of sockets is impossible to see. Between the curved megasetae and the apical tooth with two widely-separated megasetae. Near the base of the apical tooth with two or three strong setae diverging from other nearby setae, at least one of which has a curvature near base. Posteriorly to the ventral intercoxal area with a small pit, not like the other species. Tegmen very pale in this specimen and the details difficult to see: it seems rather simple.

Female unknown.

Discussion. Keilbachia foveolata is similar to K. rima . It is distinguished by having two palpomeres instead of three and by lacking a megaseta at the base of the apical tooth of the gonostylus. In K. foveolata there are two or three strong setae ventrally near the base of the apical tooth of the gonostylus, which differ distinctly from the other nearby setae; in K. rima such setae are lacking. K. foveolata differs from K. rima by having a small sclerotized pit medially in the membrane on the intercoxal area of hypopygium. In this respect, K. foveolata resembles Keilbachia sp. 3, but the latter has three palpomeres.

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 4. Wing, dorsal view. A, Keilbachia flabellata sp. n. (holotype). B, K. foveolata sp. n. (holotype). C, K. gigas sp. n. (holotype). D, K. rima sp. n. (paratype). Scale 1.0 mm.

FIGURE 8. Eye bridge (A, B), frontal view, part of hypopygium (C, E) and gonostylus (D, F), ventral view. A, E, F, Keilbachia gigas sp. n. (holotype). B, C, D, K. foveolata sp. n. (B, D, E holotype, C non-type). Scale 0.10 mm.