Sulcomesitius impressus Xu, He & Terayama, 2003

Wang, Chunhong, He, Junhua & Chen, Xuexin, 2024, Revision of subfamily Mesitiinae (Hymenoptera, Bethylidae) from China, European Journal of Taxonomy 960 (1), pp. 1-61 : 35-38

Sulcomesitius impressus Xu, He & Terayama, 2003

Fig. 12

Sulcomesitius impressus Xu, He & Terayama, 2003: 324–325 .

Material examined

Holotype

CHINA – Guangxi • ♀; Longsheng County, Huaping Nature Reserve ; [25.39˚ N, 109.55˚ E]; 23 Jun. 1982; Junhua He leg.; ZJUH 823323 .

Other material (1 ♀)

CHINA – Guizhou • 1 ♀; Leigong Mountain , Xiaodanjiang ; 4–5 Jun. 2005; Jingxian Liu leg.; ZJUH 20059386 .

Re-description

Female

MEASUREMENTS (n = 2). Body length 6.35–6.38 mm; length of fore wing 3.02–3.57 mm; LH 1.03–1.04 × WH; WF 1.32–1.33 × LE; LE 1.63–1.77 × DEV; POL 1.32–1.34× AOL; OOL 0.79–0.81× WOT; DPV 2.02–2.11 × DAO; malar space 1.07–1.47× distance between posterior ocelli and vertex crest; median length of dorsal surface of MPC 0.90–0.92× its half-width; length of PPP 0.45–0.46 × median length of dorsal surface of MPC.

COLOURATION. Body black. Mandible brown, maxillary palpi and labial palpi brown. Antenna black, yellowish brown ventrally, scape, pedicel and flagellomeres I–II brown. Fore wing bi-banded, veins brown, pterostigma yellowish brown. Legs brown. T 2 posteriorly and T 3–4 yellowish brown.

PUBESCENCE. Body with short setae; maxillary palp, labial palp and antenna with dense appressed setae ( Fig. 12C ). Eye with sparse erect setae, 5.0× diameter of an ommatidium. Setae of metasoma longer than setae of head and mesosoma; T 1 with sparse setae posterolaterally; T 2 with dense setae, basal triangular area glabrous. Wings with dense short yellowish-brown setae.

HEAD. Length nearly equal to width, LH 1.03 × WH. Mandible with four apical teeth, ventralmost largest with apex sharp. Clypeus trilobite; medio-clypeal lobe with anterior margin acute medially; medio-clypeal carina not extending into frons, arched in lateral view. Antenna distinctly thickened, at least flagellomeres II–IX shorter than wide. Frons coriaceous and densely foveolate ( Fig. 12B ); WF 1.33 × LE. Contour of eye distinctly protruding in antero-dorsal view, LE 0.41 × LH, LE 1.63 × DEV. Anterior ocellus entirely anterior to imaginary top line of eyes; POL 1.34 × AOL, OOL 0.79 × WOT, DPV 2.11 × DAO. Sides of head behind eyes rounded and slightly converging posteriorly. Vertex coriaceous and densely foveolate, vertex crest slightly protruding. Malar space 1.2× distance between posterior ocelli and vertex crest. Gena coriaceous, densely foveolate. Occipital carina complete, occiput coriaceous with shallow punctures. Medioccipito-genal suture present. Hypostomal sulcus present.

MESOSOMA. Dorsal pronotal area coriaceous and densely foveolate, median length 0.57 × width along posterior pronotal margin; median pronotal sulcus present ( Fig. 12D ); lateral pronotal area obliquely striate; cervical pronotal area coarse. Mesoscutum distinctly elevated, coriaceous with dense punctures ( Fig. 12E ); median mesonotal sulcus incomplete, present on posterior one-third ( Fig. 12E ); notauli complete, incurved posteriorly ( Fig. 12E ); parapsidal signum incomplete, absent on anterior one-third; lateral area of mesoscutum depressed anteriorly. Mesoscutellum coriaceous, densely foveolate; mesoscutum-mesoscutellar sulcus present, laterally dilated ( Fig. 12E ). Median length of dorsal surface of MPC 0.90 × its half-width; metapostnotum strongly areolate, metapostnotal median carina complete, metapostnotal-propodeal carina complete and converging posteriorly; dorsal propodeal area transversely striate; paraspiracular and lateral marginal carina of MPC complete, lateral marginal carinae straight ( Fig. 12F ); propodeal declivity areolate, median and lateral carinae complete; length of PPP 0.45 × median length of dorsal surface of MPC. Lateral surface of MPC areolate, anterior metapleural area transversely striate. Propleuron coriaceous and foveolate. Mesopleuron coriaceous and densely foveolate; subalar impression weak; posterior oblique sulcus of mesopleuron present and foveolate; postepicnemial sulcus weak; ventral surface of mesopleuron coriaceous and shallowly foveolate.

WINGS. Fore wing with 2r-rs&Rs 2 v slightly curved apically, 0.79 × length of Sc+ R 2 v; posterior margin of pterostigma straight, prestigma absent ( Fig. 12H ); Cu 2 v present as yellowish-brown trace. Hind wing with four distal hamuli.

METASOMA. Metasomal terga shiny with punctures; T 1 with tiny sparse punctures; T 2 with dense, variably sized punctures, posterior margin without punctures ( Fig. 12G ); T 3–5 with three semicircular impressions on posterior margin. Metasomal sterna shiny with punctures; S1 irregularly striate, metapostnotal median carina weak; S2–3 with dense punctures separated by less than 2.0 × their diameter.

Male

Unknown.

Distribution

China (Guangxi, Guizhou) ( Fig. 20 ).

Figures

Fig. 12. Sulcomesitius impressus Xu, He & Terayama, 2003, holotype, ♀ (ZJUH 823323). A. Habitus, lateral view. B. Head, antero-dorsal view. C. Antenna. D. Pronotum, dorsal view. E. Mesonotum, dorsal view. F. MPC, dorsal view. G. T2, dorsal view. H. Fore wing. Scale bars: A, C–H = 0.20 mm; B = 0.15 mm.

Fig. 20. Distribution map of species of Mestiinae from China.