Keilbachia acumina Vilkamaa, Menzel & Hippa

Zhang, Su-Jiong, Huang, Junhao, Wu, Hong & Wang, Yi-ping, 2010, The genus Keilbachia Mohrig from Mainland China, with descriptions of two new species (Diptera, Sciaridae), ZooKeys 52, pp. 47-56 : 48-49

Keilbachia acumina Vilkamaa, Menzel & Hippa

Keilbachia acumina Vilkamaa, Menzel & Hippa, 2009: 4.

Diagnostic characters.

(Male). Body length 1.51-1.57 mm; wing length 1.25-1.28 mm.

Eye bridge three facets wide. Prefrons with 3-5 setae. Length/width of 4th flagellomere 2.35-2.71.

Anterior pronotum with 3-4 setae. Episternum 1 with 4-5 setae.

Length of spur/width of protibia 1.55-1.57.

c/w 0.64-0.65, R1/R 0.72-0.75, r-m with no setae.

Gonostylus with two megasetae widely apart, one at subapical and stout, the other at apical third and slender (Fig. 6). Basal third of gonostylus excavated, with a long and strongly curved subbasal mesial megaseta on broad basal body. Tegmen simple, much broader subbasally than subapically, with sparsely placed teeth.

Specimens examined.

1 male, China, Zhejiang, Linan, Mt. Xijingshan, 30°23'N; 119°72'E, sweep-net, 21.VI.2008, Su-Jiong Zhang [SM00018] (ZAFU); 1 male, China, Zhejiang, Lishui, Mt. Jiulongshan, 28°59'N; 119°25'E, sweep-net, 10.X.2008, Su-Jiong Zhang [SM00114] (ZAFU); 1 male, Yunnan, Tengchong, Shaba, Mt. Tiantaishan, 25°24.524'N; 98°42.735'E, sweep-net, 13.V.2009, Su-Jiong Zhang [SM00933] (ZAFU).

Distribution.

China (Zhejiang, Yunnan), Japan.

Biology.

Unknown.

Remarks.

The species is similar to Keilbachia subferrata Rudzinski and Keilbachia ferrata (Hippa & Vilkamaa) by having a rather long subbasal mesial megaseta on a large basal body, But it can be distinguished from Keilbachia subferrata by the smaller mesial megaseta in a more apical position ( Vilkamaa et al. 2009), and differs from Keilbachia ferrata by having the basal body slightly smaller, and the socket of the apical megaseta more distinct ( Vilkamaa et al. 2009). Vilkamma et al. (2009) mentioned Keilbachia acumina shows intraspecies variation in the structure of the gonostylus and the length of the flagellomeres. The variations are also examined in the Chinese materials, that the position of basalmost subapical megasetae varies in the apical third of gonostylus and the length of the 4th flagellomere among 67.63-87.58 um.