Monelata truncata Hou & Xu

Hou, Zi & Xu, Zai-fu, 2016, Description of a new species of the genus Monelata Foerster, 1856 from China (Hymenoptera, Diapriidae), ZooKeys 574, pp. 97-104 : 99-102

Taxon classification Animalia Hymenoptera Diapriidae

Monelata truncata Hou & Xu sp. n. Figs 1-3, 4-5

Material examined.

Holotype: ♀, CHINA: Yunnan, Zhaotong, Yongshan, Huanghua, 2012. VIII–X, Shi-wen Yang (SCAU). Paratypes: 22 ♀♀ 35 ♂♂, Yunnan, Zhaotong, Yongshan, Huanghua, 2012. VIII–X, Shi-wen Yang (SCAU).

Description.

Holotype. Female (Figs 1-3). Body length 0.9 mm. Fore wing length 0.8 mm.

Color. Head black. Antenna dark brown, with A13 black. Mesosoma and metasoma black. Petiole and legs brown. Fore and hind wings hyaline, with veins brown.

Head. Head in dorsal view transverse, 0.75 times as long as wide. Relative proportion of length to width of antennal segment as follows: A1 (10.5: 2.2); A2 (3.5: 1.8); A 3 (1.6: 1.3); A4 (1.2: 1.3); A5 (1.2: 1.3); A6 (1.2: 1.3); A7 (1.2: 1.3); A8 (1.3: 1.4); A9 (1.4: 1.5); A10 (1.6: 1.6); A11 (1.8: 2.0); A12 (2.2: 2.3); A13 (7.5: 4.5). A1 slender, cylindrical, unarmed apically. A10 to A13 gradually enlarged. A13 ovoid, remarkably clavate. Eye oval, 1.5 times as long as wide, 1.5 times as long as malar space. Posterior orbit of eye not sinuate. POL: OOL: OL = 1.5: 4.0: 1.5.

Mesosoma. Mesosoma as wide as head. Cervix densely hairy, dense pronotal and propleural cushions confluent into complete hairy collar ventrally and dorsally. Mesoscutum smooth, with three pairs of setae. Scutellar disc slightly converging posteriorly. Mesopleuron smooth. Metanotum with a median keel. Metapleuron covered with long hairs. Propodeum elongate, with a distinct median keel, pointed anteriorly. Posterior margin of propodeum excavate. Fore wing elongate, distinctly longer than mesosoma and metasoma; apical margin truncate (Fig. 3); apical margin with long fringes, 1/3 of wing width. Hind wing narrow, with fringes distinctly longer than wing width. Legs long and slender.

Metasoma. Petiole cylindrical, 1.5 times as long as wide. Petiole covered by dense, translucent, elongate setae. T2 enlarged, cover 0.8 length of gaster, 1.7 times as long as wide.

Male (Figs 4, 5). Body length 0.8 mm. Fore wing length 0.7 mm. Antenna fully brown. Relative proportion of length to width of antennal segment as follows: A1 (11.0: 2.0); A2 (3.2: 1.8); A3 (3.8: 1.9); A4 (3.8: 1.9); A5 (3.8: 2.0); A6 (3.8: 2.0); A7 (3.8: 2.0); A8 (3.8: 2.0); A9 (3.8: 2.0); A10 (3.8: 2.0); A11 (3.8: 2.0); A12 (4.0: 2.1); A13 (4.0: 2.1); A14 (5.0: 2.1). Eye 1.4 times as long as wide, 2.3 times as long as malar space. POL: OOL: OL = 1.5: 4.0: 1.3. A4 not sexually modified. Other characteristics are similar to females.

Variation.

Females. Body length 0.8-1.0 mm. Fore wing length 0.8-0.9 mm. Males. Body length 0.7-0.8 mm. Fore wing length 0.6-0.7 mm.

Distribution.

China (Yunnan).

Etymology.

The species name “truncata” is based on the truncate apical margin of fore wing.

Remarks.

This is the third species of the genus Monelata in the Oriental Region, but it can be separated from the other two Oriental species, Monelata incisipennis Huggert and Monelata completa Rajmohana & Narendran by the following characteristics: fore wing with apical margin truncate (deeply incised in Monelata incisipennis , and round in Monelata completa ); head in dorsal view distinctly transverse (nearly as long as wide in the latter two); and mesosoma black (reddish-brown to brown in the latter two).

According to the key and figure of Nixon (1980), Monelata solida (Thomson, 1858) in the Palearctic Region is "forewing faintly to hardly emarginate at apex", the new species is similar to Monelata solida . But after we checked the holotype of Monelata solida (Holotype ♀, BMNH No. 9.688) in London, the apical margin of fore wing of Monelata solida is round as Monelata completa . The new species also can be separated from Monelata solida by head in dorsal view distinctly transverse (slightly wider than long in Monelata solida ); female A7-A12 slightly wider than long, or as wide as long (distinctly wider than long in Monelata solida ); A12 1.67 times as long as wide (2.27 times in Monelata solida ).