Keilbachia subacumina Wu & Zhang

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 : 49-50

Keilbachia subacumina Wu & Zhang sp. n. Figs 1-5

Description.

(Male). Body length 1.81-2.32 mm; wing length 1.49-1.52 mm.

Color. Head, thorax and abdomen brown; antenna, palpus, coxae, and hypopygium yellowish-brown; leg yellow; wing fumose.

Head (Figs 1, 2). Eye bridge 3-4 facets wide. Prefrons with 5-6 setae, clypeus with 0-1 seta. Palpus three-segmented. Basal segment with one seta, with a narrow sensory pit, 2nd segment with 4-6 setae, 3rd segment with 6-7 setae. Length/width of 4th flagellomere 2.74-2.79.

Thorax. Anterior pronotum with 5-6 setae. Episternum 1 with 6-7 setae.

Legs. Apex of protibia (Fig. 3). Length of spur/width of protibia 1.79-1.83. Length of profemur/length of protibia 0.76-0.79. Length of metatibia /length of thorax 1.23-1.31.

Wings.Width/length 0.44-0.49. c/w 0.71-0.77, R1/R 0.96-0.98. r-m with 1-2 setae.

Abdomen. Sternite 8 with 10-11 setae. Gonostylus and gonocoxa subequal in length. Gonostylus with two megasetae widely apart, one at apex and stout, the other at apical half of gonostylus and slender. Basal third of gonostylus excavated, with a long and strongly curved mesial megaseta on broad basal body. Tegmen simple, much broader subbasally than subapically, with sparsely placed teeth. (Figs 4, 5).

Specimens examined.

Holotype, male. China, Zhejiang, Linan, Mt. Xijingshan, 30°23'N; 119°72'E, sweep-net, 21.VI.2008, Su-Jiong Zhang [SM00025] (ZAFU). Paratypes. 2 males, same data as holotype [SM00018, SM00024] (ZAFU); 5 males, same data as holotype but 19.VII.2008 [SM00057-00061] (ZAFU). China, Zhejiang, Lishui, Mt. Fengyangshan, 28°04'N; 119°08'E. sweep-net, 3 males, 11.VIII.2008, Sheng-Long Liu [SM00282] (ZAFU); 1 male, 24.VIII.2008, Sheng-Long Liu [SM00231-00233] (ZAFU); 1 male, 01.VIII.2008, Xiao-Ling Niu [SM00306] (ZAFU). 1 male, China, Zhejiang, Lishui, Mt. Jiulongshan, 28°59'N; 119°25'E, sweep-net, 10.X.2008, Su-Jiong Zhang, [SM00114] (ZAFU).

Biology.

Unknown.

Remarks.

This species is very similar to Keilbachia acumina in the structure of the hypopygium (Fig. 5, 6), but Keilbachia subacumina can be distinguished by having the apex of gonostylus broader, and the stouter and shorter basalmost megaseta at the apical half of the gonostylus. What’s more, the anterior pronotum bears 5-6 setaein Keilbachia subacumina while 3-4 setae in Keilbachia acumina , and the r-m nervation of the wing with 1-2 setae in Keilbachia subacumina while bare in Keilbachia acumina . The structure of the hypopygium in the new species does not show distinct intraspecies variation. The species is named after its similarity to Keilbachia acumina . This epithet is an adjective.