Lycogaster umbonata Chen & van Achterberg sp. nov.

Figs 4, 5, 6

Diagnosis.

Antenna elongate and hardly widened medially (Figs 4A, 6A); second sternite of female with a strong lobe-shaped protuberance medio-apically (Fig. 5E); mandibles with ivory patches (Figs 4B, 6B); second tergite of female strongly shiny and with elliptical depressions antero-laterally (Fig. 5D); wing membrane subhyaline and without darkened (Figs 4A, 5A, 6A).

Description.

Female. Holotype, length of body 5.1 mm (of fore wing 4.1 mm).

Head. Antenna with 21 segments, elongate and hardly widened medially (Fig. 4A); frons spaced punctate and shiny, with distinct median depression (Fig. 4B); vertex and temple largely smooth and shiny with sparse and fine punctures (Figs 4B, C); head subparallel-sided behind eyes, distinctly narrowed posteriorly and 1.3 × as long as mesoscutum (Fig. 4C); dorsal length of eye approximately as long as temple (Fig. 4C); occipital carina narrow lamelliform and with weak crenulae medio-dorsally (Fig. 4C); supra-antennal elevations hardly developed as a thin rim and smooth, 0.3 × as long as scapus (Fig. 4C); clypeus emarginate and comparatively thin medio-ventrally (Fig. 4B).

Mesosoma. Length of mesosoma 1.8 × as its height (Fig. 5C); mesopleuron below transverse mesopleural groove rugose to punctate anteriorly, largely smooth and shiny posteriorly, above groove similar but rugose anteriorly (Fig. 5C); notauli narrow anteriorly, widened posteriorly and coarsely crenulate; middle lobe of mesoscutum sparsely and rather finely punctate anteriorly, coarsely punctate at posterior end, lateral lobes sparsely and rather finely punctate (Fig. 5B); scutellar sulcus wide, both medially and laterally and coarsely crenulate (Fig. 5B); scutellum largely smooth with sparsely and finely punctate, distinctly shiny, rather flat and anteriorly near level of mesoscutum; metascutellum shiny and smooth medio-posteriorly (Fig. 5B); propodeum largely obliquely rugulose to rugose with smooth interspaces anterio-laterally (Fig. 5B); posterior propodeal carina thick lamelliform and distinctly arched, foramen approximately 1.5 × as wide as high medially (Fig. 5B).

Wings. Fore wing: length of vein 1-M 1.8 × as long as vein 1-SR; second submarginal cell 1.4 × as long as third submarginal cell (Fig. 5A).

Metasoma. First tergite 0.5 × as long as its apical width, smooth, with rather distinct elliptical depression medially and basal half with several distinct coarse transverse rugae medially (Fig. 5D); second tergite with elliptical depressions antero-laterally; second-fifth tergites largely smooth with sparse fine punctures (Fig. 5D); sternites sparsely and finely punctate (Fig. 5F); second sternite strongly convex in lateral view, with a strong lobe-shaped protuberance medio-apically (Fig. 5E); third sternite about 0.2 × as long as second sternite, with distinct ledge (Fig. 5F); hypopygium truncate apically (Fig. 5F).

Colour. Black; mandibular teeth and palpi dark brown; anterior-basal part of mandible ivory (Fig. 4B); distal of fumer, tibia, tarsus and claw yellow to brownish (Fig. 4A); pterostigma dark brown; wing membrane subhyaline and without darkened (Fig. 4A).

Male. Paratype, length of body 5.9 mm, of fore wing 4.5 mm; antenna with 21 segments and without tyloids (Fig. 6A); vertex densely and coarsely punctate; sculpture of mesosoma coarser than that in female (Fig. 6B); second tergite with a round depression antero-medially; second-fifth tergites and sternites densely and rather fine punctate, except sparsely and coarsely punctate in big round area of third tergite medially (Figs 6C-E); genitalia extruded (Fig. 6D); ivory part of mandible larger than that of female; clypeus with ivory patches (Fig. 6B); large part of hind tibia, hind tarsus and hind claw brown (Fig. 6A), not like that in female.

Etymology.

Named after the strong lobe-shaped protuberance of female second sternite: from " umbo " (Latin for "rounded protuberance").

Material examined.

Holotype, female, China: Yunnan, Baoshan City, Longyang Dist., 2390 m, 25°17'57.26"N, 98°46'11.35"E, 15-30.IX.2020, Lang Yi leg., MT, SYSBM En-419021 (deposited in SYSBM); GenBank: OM057968 . Paratype, 1 male, China: Yunnan, Baoshan City, Longyang Dist., 2390 m, 25°17'57.26"N, 98°46'11.35"E, 30.VII-15.VIII.2020, Lang Yi leg.,MT, SYSBM En-419022 (SYSBM); GenBank: OM057967 .

Distribution.

China (Yunnan). Collected at 2390 m.

The key to Chinese species of Lycogaster published by Chen et al. (2014) could be updated to accommodate L. umbonata by replacing couplet 2 as follows: