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

Hippa, Heikki & Vilkamaa, Pekka, 2007, New species and records of Keilbachia Mohrig (Diptera, Sciaridae) from the Oriental region, Zootaxa 1622, pp. 57-68 : 66

Keilbachia orthonema sp. n.

Fig. 6 A–E.

Material studied. Holotype male. MALAYSIA, Borneo, Sabah, Mt. Kinabalu N. P., Laban Rata, 3200 m, 9.– 20.5.1987, A. Smetana (in BMNH). Paratypes. 1 male with same data as holotype (in BMNH).

Male. Colour. Almost unicolorous yellowish-brown, vertex darker brown, abdomen slightly paler than thorax, wing hyaline brownish, haltere pale brown. Head. Eye bridge 4 facets wide. Face (prefrons) with 10– 11 setae, which are widely spread. Clypeus with 0–1 setae. Maxillary palpus, Fig. 6 A: with 3 palpomeres. Palpomere 1 with 1seta, with a large low sensory pit. Palpomere 2 with 6–7 setae. Palpomere 3 with 6–8 setae. Antennal flagellomere 4, Fig. 6 B. Thorax. Anterior pronotum with 5 setae. Episternum 1 with 5–6 setae. Wing similar to Fig. 5 D. Length 1.7–1.9 mm. Width/length 0.45–0.50. R1/R 0.75, calculated only for the paratype because the costal margin is slightly folded in the holotype. c/ w 0.80 –0.85. r-m and bM equally long, r-m/bM 1.00–1.10, both non-setose or r-m with 1n seta near Rs. Legs. Apex of fore tibia, Fig. 6 C. Length of fore basitarsomere/length of fore tibia 0.50–0.55. Length of fore tibia/length of fore femur 1.10–1.15. Length of hind tibia/length of scutum+scutellum 2.00–2.10. Hypopygium Fig. 6 D, E: Gonostylus with the curved megaseta rather short and straight, slightly longer than its basal body, with two additional megasetae at the apex. Tegmen simple.

Female unknown.

Discussion. Keilbachia orthonema resembles the two other species from Borneo: K. adunca and K. clinata . It is distinguished from both e.g. by having a sensory pit on the first palpomere and by having megasetae at the apex of the gonostylus. K. orthonema is similar to K. apprima , known from Myanmar. It is distinguished e.g. by having the curved megaseta on the gonostylus longer and much less curved and by having the apical megasetae of the gonostylus more slender. Furthermore, it differs by having a distinct sensory pit on palpomere 1 and by having most of the subapical prolateral setae of fore tibia in a transverse row instead of forming a less arranged patch.

Figures

FIGURE 5. Keilbachia mirabilis sp. n. (B, C, E, F holotype, A, D paratypes). A: Maxillary palpus, dorsal view. B: Antennal flagellomere 4, ventral view. C: Apical part of tibia 1, prolateral view. D: Wing, dorsal view. E: Part of hypopygium, ventral view. F: Gonostylus, ventral view. Scale 0.05 mm, for D 0.5 mm.

FIGURE 6. Keilbachia orthonema sp. n. (B, D, E holotype, A, C paratype). A: Maxillary palpus, dorsal view. B: Antennal flagellomere 4, ventral view. C: Apical part of tibia 1, prolateral view. D: Part of hypopygium, ventral view. E: Gonostylus, ventral view. Scale 0.10 mm.