Rhoptrocentrus quercusi Yan
Creators: name: Cao, Liangming
name: Yang, Zhongqi
name: Tang, Yanlong
name: Wang, Xiaoyi
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Braconidae
Rhoptrocentrus
Rhoptrocentrus quercusi

description: Rhoptrocentrus quercusi Yan g et Cao sp. nov.   
(Figs 8, 15–26)  
 Type material. Holotype, ♀, China, Liaoning Province, Kuandian County, Daxicha Forest, 1.VI.2009, N40°44′ 58″, E125°11′ 35″, 446 m altitude, Yang Zhongqi and Tang Yanlong collected cocoons, 8.VI.2009 emerged. Paratypes, 1♀2♂♂, same data as holotype.   
 Description. Body length. ♀/♂ = 3.29–3.31/ 2.34–2.37 mm.   
 Color. Body black; eyes silvery white; scape and pedicel, flagellum 1–3 joints, maxillary palp, labial palp, legs, ridged portion of median metasomal sternum yellow to brownish yellow; apical 1/3 of each femur with dark irregular spot; female ovipositor brown (Figs 15, 16).   
 Head. Median length as long as its width in dorsal view; vertex with sparse and shallow wrinkles, each wrinkle centrally with concave dot; eyes big, transverse diameter 1.02 × length of temple, temple slightly swollen behind eyes (Fig. 19); face with wide transverse wrinkles; basal clypeus slightly concave, clypeus triangular; width of hypoclypeal depression 0.65 × width of face, malar space 0.83 × height of eye and 0.59 × basal width of maxillary palp (Fig. 18); antenna 24 segments, scape 2.25 × length pedicel, first segment of flagellum slightly longer than the second segment (Fig. 17); antenna about 0.77 × body length, about as long as fore wing; maxillary palp same length as head length, six-segmented (Fig. 22).   
 Mesosoma. In lateral view, length twice of maximum height (Fig. 23). Depressed sulcus on pronotum wide and shallow, lateral pronotum with irregular sculptures; anterior mesoscutum steep, with dense disordered small sculptures, notauli and their meeting portion depressed, lateral mesonotal lobe snakeskin-sculptured; scutellar sulcus broad and shallow, median with 1 longitudinal ridge; lateral margin of scutellum ridged basally, 2/3 apically of scutellum smooth, slightly swollen; posterior margin of metanotum ridged, with median and bilateral portion sculptured; propodeum half length of mesosoma, with an inversed “Y”-shaped ridge (Fig. 20).   
 Legs. Fore coxa with a big odontoid process medially, its length about 2/3 width of coxa; trochantellus as long as coxa; fore femur 0.94 × length fore tibia, and twice of its maximum width; basal 1/3 to sub-apex with 10–12 spines; ratio of fore tarsi I–V = 4:2:1.4:0.8:1.7 (Fig. 24); mid tibia with 11–12 spines medially, apex with two tibial spurs, mid femur 0.83 × length of mid tibia, length ratio of mid tarsi I–V = 3:1.7:1.3:0.7:1.8 (Fig. 25); length of hind femur 0.63 × hind tibia (Fig. 26).   
 Wings. Fore wing 3.86 × as long as its maximum width; pterostigma 5.5 × as long as its width; 1-R1 about 1.59 × length of pterostigma; radial vein arising from basal 1/3 of pterostigma; SR1 about 1.55 × length of 3-SR; radial vein about 0.6 × length of 2-SR, and 0.27 × length of 3-SR; cu-a vein postfurcal and oblique, m-cu vein enters into second submarginal cell; 1-SR+M vein straight; 1-SR vein about 1/2 length of 1-M vein; r-m vein weakly sclerotized; 3-M and CU1a vein not reaching apex of fore wing (Fig. 15).   
 Metasoma. Elongate-oblong, first tergite and basal 1/3-1/2 second tergite with irregular striations, other tergites smooth; first tergite length as long as its apical width, first spiracle located at 1/4 sub-basally. Length ratio of tergite I–VII as 4:3.5:4:1.7:1.8:2.1:1.7; Ovipositor 1.35 × body length (Fig. 21).   
 Male. Antenna 16 segments, other characters are similar to female.   
 Distribution. China (Liaoning).   
 Etymology. The new species name derived from the generic name of the tree Q. liaotungensis, the host plant of the longhorned beetle.   
 Diagnosis. The new species is similar to R. piceus Marshall, and it can be distinguished from the latter as follows: 1. Length of ovipositor 2.6 × length of metasoma (Figs. 15, 16) (ovipositor of R. piceus is 2.0 × length of metasoma); 2. Fore wing CU1a arising from middle of 3-CU1 and CU1b combined (Fig. 15) (fore wing of R. piceus withCU1a arising from upper 1/3 of 3-CU1 and CU1b combined); 3. Sulcus present between second and third metasomal tergites (Fig. 21) (R. piceus without such sulcus, second and third metasomal tergites fused); 4. Basal 1/3 to 1/2 of second metasomal tergite with distinct striations (Fig. 21) (R. piceus with basal 1/4 having such striations); 5. Propodeum with an inversed “Y”-shaped ridge (Fig. 20) (R. piceus without such ridge); 6. Coxae yellow, femora yellowish brown, apical 2/3 of hind tibiae and basitarsi slightly dark brown, other segments of tarsi yellowish brown (Figs. 15, 16) (R. piceus femora dark brown, hind tarsi yellowish brown); 7. Face with distinct transverse striations (Fig. 18) (face of R. piceus with sculptures and tiny depressions); 8. Posterior 1/3 of mesonotum with a longitudinal ridge (Fig. 20) (R. piceus without such ridge).   
 Host. This species parasitizes the second instar larva of M. raddei. Seven cocoons which connected each other and beside a host mummy were collected from the longhorned beetle gallery, and then reared in the laboratory. Only four adult wasps (2♀ 2♂, see types) were successfully emerged.   
 Remarks. Rhoptrocentrus Marshall comprises three known species (Yu et al. 2012), i.e. South Palaearctic R. claeopatrae, Holarctic R. piceus, and Australasian R. yarramanensis (Belokobylskij & Maeto 2009). Here R. quercusi sp.n. is the fourth described species of this small genus.
description: Published as part of Cao, Liangming, Yang, Zhongqi, Tang, Yanlong & Wang, Xiaoyi, 2015, Notes on three braconid wasps (Hymenoptera: Braconidae, Doryctinae) parasitizing oak long-horned beetle, Massicus raddei (Coleoptera: Cerambycidae), a severe pest of Quercus spp. in China, together with the description of a new species, pp. 467-474 in Zootaxa 4021 (3) on pages 470-471, DOI: 10.11646/zootaxa.4021.3.6, http://zenodo.org/record/244781