Mastrus rugotergalis Sheng & Zeng

Sheng, Mao-Ling & Zeng, Xiang-Fu, 2010, Species of the genus Mastrus Foerster (Hymenoptera, Ichneumonidae) of China with descriptions of two new species parasitizing sawflies (Hymenoptera), ZooKeys 57, pp. 63-73 : 67-71

Mastrus rugotergalis Sheng & Zeng sp. n. Figs 10, 11, 12

Etymology.

The specific name is derived from the longitudinal wrinkles on the second tergum.

Types.

Holotype, female, CHINA: Qinyuan, Shanxi Province, 6 July 1996, Mao-Ling Sheng. Paratypes: 2 females, CHINA: Qinyuan, Shanxi Province, 5 June 1995. 4 females 2 males, CHINA: Qinyuan, Shanxi Province, 6 July 1996, Mao-Ling Sheng; 1 female, CHINA: Qinyuan, Shanxi Province, 12 June 1999, Guo-Fa Chen. 1 female (reared from a pupa of moth), CHINA: Weichang, 1673 m, Chengde, Hebei Province, 16 June 2010, Tao Li.

Diagnosis.

Malar space 1.1-1.2 times as long as basal width of mandible. Hind wing vein 1-cu strongly inclivous, about 4.0 times as long as cu-a. Area superomedia 1.3 to 1.7 times as wide as long. Second tergum with longitudinal wrinkles. Tegulae darkish brown.

Description.

Female. Body length 5.5-6.5 mm. Fore wing length 3.8-4.0 mm. Ovipositor sheath length 2.0-2.2 mm.

Head. Face (Fig. 11) 1.9-2.0 times as wide as long, with granulose texture and indistinct fine punctures, diameter of punctures 0.5-2.0 times distance between punctures, evenly convex centrally; upper margin with a small median protuberance. Clypeal suture weak and unclear. Clypeus slightly convex, 2.2 times as wide as long; basal portion with indistinct fine punctures, apically smooth and sparsely punctate; apical margin with two small median protruberances. Mandible with indistinct sparse punctures, upper tooth distinctly longer than lower tooth. Cheek finely granulated. Malar space 1.1-1.2 times as long as basal width of mandible. Without subocular sulcus. Gena with fine leathery texture and fine punctures, about 0.9 times as long as middle width of compound eye. Vertex with texture as that of gena. Postocellar line about as long as ocular-ocellar line. Upper portion of frons approximately flat, with texture as that of face, but distinctly punctate; lower portion concave and shiny. Antenna with 23 to 24 flagellomeres, apical portion not attenuated, ratio of length from first to fifth flagellomeres: 5.2:5.0:4.2:3.3:2.9. First and second flagellomeres about 3.7 and 3.3 times as long as respective widest diameter. Occipital carina complete.

Mesosoma. Anterior portion of pronotum smooth, upper portion with punctures; median portion with dense oblique transverse wrinkles; upper posterior portion with fine granulose texture, punctures distinct. Epomia weak. Mesoscutum with fine granulose texture, punctures indistinct. Notaulus evident on front portion of mesoscutum. Scutoscutellar groove nearly smooth, with weak longitudinal wrinkles. Scutellum shiny, evenly convex, with fine punctures, diameter of puncture 1.0 to 3.5 times as long as distance between punctures. Postscutellum transverse, anterolaterally deeply concave, punctures indistinct. Mesopleuron with dense and oblique transverse wrinkles, upper anterior corner with weak and short transverse wrinkles. Epicnemium with fine punctures, diameter of puncture approximately as long as distance between punctures. Epicnemium punctate indistinctly. Epicnemial carina strong, upper end reaching to subalar prominence. Speculum small, anterior portion with weak and fine transverse lines. Sternaulus sharp, reaching to hind margin of mesopleuron. Metapleuron slightly rough, with unclear oblique transverse wrinkles. Juxtacoxal carina anteriorly distinct, hind section unclear. Juxtacoxal and submetapleural carinae complete and strong. Wings brownish hyaline. Fore wing with vein 1cu-a distal of 1/M by about 0.3 times length of 1 cu-a. Vein 3rs-m absent; 2rs-m about 1.1 to 1.3 times as long as distance between it 2rs-m and 2m-cu. Vein 2-Cu approximately 2.0 times as long as 2cu-a. Hind wing vein 1-cu strongly inclivous, about 4.0 times as long as cu-a. Legs robust. Ratios of length of hind tarsomeres 1:2:3:4:5 are 10.0:4.2:3.0:1.7:3.0. Propodeum completely areolate, carinae strong. Area basalis inverse trapezium, almost smooth. Area superomedia hexagonal, 1.3 to 1.7 times as wide as long, slightly coriaceous. Costula connecting area superomedia at its apical 0.3. Area petiolaris strongly sloping, centrally rough, with short oblique wrinkles. Area dentipara with irregular fine wrinkles. Area posteroexterna with strong irregular wrinkles. Areae spiracularis and lateralis with irregular transverse wrinkles. Spiracle circular, very small, close to lateral longitudinal carina. Propodeal apophysis short and compressed.

Metasoma. First tergum 1.4 to 1.6 times as long as apical width. Petiole with granulose texture. Postpetiole with fine, longitudinal wrinkles. Without median dorsal carinae. Dorsolateral and ventrolateral carinae complete. Spiracle circular, very small, slightly convex, located at apical 0.4 of first tergum. Second tergum (Fig. 12) approximately 0.6 times as long as apical width, with more or less distinct longitudinal wrinkles. Third tergum 0.6 times as long as basal width, 0.7 times as long as apical width, almost smooth. Fourth and following terga strongly convergent backward. Ovipositor sheath 1.1 to 1.2 times as long as hind tibia. Ovipositor not compressed, with weak nodus. Apical portion of lower valve with weak oblique ridges, basal 2 widely spaced.

Color

(Fig. 10). Black, except the following. Ventral profiles of scape and pedicel, flagellomeres 1 to 4 (5), legs except hind tibiae and tarsi slightly darkish brown, brown. Mandible yellowish brown, except teeth black. Maxillary and labial palpi dust-coloured. Longitudinal fleck of median portion of petiole, postpetiole, second and third terga, basal median portion of fourth tergum red. Tegulae darkish brown. Posterior margins of sixth and seventh terga and most of eighth tergum white. Stigma, except white base and veins, blackish brown.

Male. Body length about 5.0 mm. Fore wing length about 4.0 mm. Face with distinct punctures. Antenna with 21 flagellomeres, tenth and eleventh flagellomeres with linear tyloids. Ventral profiles of scape and pedicel whitish yellow. Tegulae buff. Middle and hind coxae blackish brown. Second and third terga brown with more or less irregular darkish fleck.

Host.

Diprion jingyuanensis Xiao & Zhang ( Hymenoptera : Diprionidae ). Pupa of moth ( Lepidoptera ).

Host plant.

Pinus tabulaeformis Carr. ( Pinaceae ).

Remarks.

This new species is similar to Mastrus deminuens but can be distinguished from the latter by the following combination of characters: face distinctly and densely punctate on a slightly granulate background; second tergum with more or less distinct longitudinal wrinkles, or finely granulose basally-centrally. Mastrus deminuens : face granulate and dull, with fine punctures; second tergum distinctly granulate and dull, or partly and obliquely granulate-strigose.