Dolichogenidea dioryctriphagous Liu & Chen, 2018

Liu, Zhen, He, Jun-Hua & Chen, Xue-Xin, 2018, The laevigata - group of the genus Dolichogenidea Mason, 1981 from China, with descriptions of 26 new species, Zootaxa 4436 (1), pp. 1-74 : 21-25

Dolichogenidea dioryctriphagous Liu & Chen , sp. n.

Figures 10 , 36

Description. Female. Body length 3.1 mm, fore wing length 3.2 mm.

Head. Almost rectangle in dorsal view, 1.9× as wide as long and weakly narrower than mesoscutum (29.0:31.0). Temple relatively dull and rough but almost impunctate, a little rounded. Face dull, pubescent, inner margin of eyes subparallel, transverse, nearly 0.7× as high as wide. Ocelli relatively large, distance between fore and a hind ocellus not longer than diameter of an ocellus, posterior imaginary tangent to fore ocellus slightly transecting hind two ocelli, POL:OD:OOL=4.5:2.4:4.0. Antenna slightly longer than body, penultimate antennomere 1.7× longer than wide.

Mesosoma. Length:breadth:height=53.0:31.0:39.0. Disc of mesonotum shiny, with shallow indistinct punctures, interspaces larger than diameter of punctures. Scutellar sulcus nearly straight, rather narrow with shallow carinae in between. Scutellum highly shiny, polished without punctures. Propodeum highly shiny, mostly highly polished, except small shallow punctures anterior-laterally, base of orifice with short radiate carinae. Mesopleuron highly polished, almost without punctures anteriorly.

Legs. Spines on outer side of hind tibia sparse. Inner spur of hind tibia half length of hind basitarsus, outer spur slightly shorter (1/3). Basitarsus of hind leg a little shorter than tarsomeres 2–4 combined (17.0:19.5).

Wings. Pterostigma 2.7× as long as its widest part. Vein 1-R1 (metacarp) weakly longer than pterostigma, almost closing the marginal cell. Vein r arising from apex of pterostigma, slightly shorter than width of pterostigma, vein r as long as vein 2-SR, distinctly angled at their meeting, vein 2-M 1/3 length of vein 2-SR. 1 st discal cell almost as wide as high. 1 st submarginal cell of hind wing 1.9× wider than high. Vein cu-a curved.

Metasoma. As long as thorax. T1 with weakly arched sides, 1.3× longer than wide posteriorly, indistinctly concave at basal 2/5, turned-over part dull, rugose, evenly wrinkled posteriorly. T2 straight apically, 3.6× wider than long in the middle, weakly finely wrinkled anteriorly and laterally. T3 1.5× longer than T2. Tergites after T2 shiny, polished, sparsely pubescent. Hypopygium shorter than apex of abdomen. Ovipositor sheath 1.8× longer than hind tibia, more or less falcate.

Colour. Body black. Tegula black. Spurs, palpi, labrum and mandible reddish yellow. Antenna and ovipositor sheath evenly brown. Legs testaceous, except coxae dark red to brown and posterior quarter of hind tibia and hind tarsus dark brown. Wing membrane hyaline, vein 1-R1, C+SC+ R and pterostigma brown, other veins light brown.

Viaration. Fore wing length 2.3–3.5mm.

Male. Unknown.

Host. According to the label: Dioryctria rubella Hampson ( Lepidoptera : Pyralidae ).

Material examined. Holotype: ♀, Changsha, Hunan, 1957.IV, Peng Jianwen, No. 573010, host: Dioryctria rubella Hampson. Paratypes : 1♀, Yuexi , Anhui, 1981. VI.9, Yang Fuan, No. 820582 ; 1♀, Baotianman, Neixiang , Henan, 1998. VII.13, Ma Yun, No. 986169 ; 1♀, Mt. Changbai , Jilin, 1994. VIII.4, Lou Juxian, No. 951 999 ; 1♀, Hangzhou , Zhejiang, 1958. IV.17, Hu Cui, No. 583212 ; 1♀, Changshan, Zhejiang, 1954, No. 543866 ; 1♀, Mt. Tianmu , Zhejiang, 1986. X.20, Wang Donglin, No. 86035.

Distribution. China (Anhui, Henan, Hunan, Jilin, Zhejiang).

Etymology. The specific name “ dioryctriphagous ”, referring to that it is a parasitoid of larva of Dioryctria rubella Hampson.

Remarks. This species is similar to D. decorus (Haliday) but differs from the latter by the following: pterostigma 2.7× as long as its widest part (the latter 2.0× longer than wide); ovipositor sheath falcate and distinctly longer than in the latter; and T1 with weakly arched sides.

Figures

FIGURE 10. Dolichogenidea dioryctriphagous Liu & Chen, sp. n. a propodeum; b habitus, dorsal view; c head, dorsal view; d ovipositor sheath; e fore and hind wings; f metasoma, dorsal view; g head, frontal view; h mesonotum and scutellum. Scale line = 0.5 mm.

FIGURE 36. Distribution map of laevigata-group of Dolichogenidea species in China. *: Dolichogenidea changbaiensis Liu & Chen, sp. n.; ■: Dolichogenidea concentricus Liu & Chen, sp. n.; Δ: Dolichogenidea dioryctriphagous Liu & Chen, sp. n.; •: Dolichogenidea fumeus Liu & Chen, sp. n.; ♥: Dolichogenidea funalicauda Liu & Chen, sp. n.;•: Dolichogenidea gansuensis Liu & Chen, sp. n.; Ŧ: Dolichogenidea indicaphagous Liu & Chen, sp. n.