Trichrysis striata Nguyen, Wiśniowski & Rosa, 2022

Nguyen, Lien Thi Phuong, Wiśniowski, Bogdan, Tran, Ngat Thi, Tran, Duong Dinh & Rosa, Paolo, 2022, Two new species of Trichrysis Lichtenstein (Hymenoptera: Chrysididae) from Vietnam and China, with taxonomic notes on other species from the Oriental region, Zootaxa 5194 (1), pp. 133-143 : 137

Trichrysis striata Nguyen, Wiśniowski & Rosa , sp. nov.

( Figs 8–15 )

urn:lsid:zoobank.org:act:AFF70930-25BA-4CDF-AF22-1345E96EC3D3

Material examined. Holotype, ♀: VIETNAM; Cao Bang, Nguyen Binh, Quang Thanh / Hoai Khao , Phia Oac-Phia Den NP / 579 m; 10.v.2021 / 22°36′39″N 105°54′40″E / [leg.] NTPL, NQC, TTN ( IEBR).

Diagnosis. Middle-sized species with robust, densely punctate body and mostly golden-green colouration with some blue colour dorsally ( Fig. 8 ). Brow prominent, TFC single, slightly convex, only laterally with traces of second carina. Area below TFC with elongate, weakly defined punctures. Scapal basin deep and punctate, punctures partially fused medially, forming transverse striae, and with large oval facial pit. Dorsal part of pedicel metallic copper. Sublateral pronotal carina fully developed ( Figs 8, 12 ). T1 and T2 bright green and blue dorsally, golden green laterally, and apically. T2 with distinct median carina, present throughout it ( Fig. 14 ). Median tooth on apex of T3 sharp and pointed ( Figs 14, 15 ), interval between median tooth and lateral tooth slightly wavy curved, pits distinct, of same size. S2 black spots triangular, fused medially, forming black mark twice wider than its length ( Fig. 13 ).

Description. Female. Holotype, body length 7.0 mm.

Head. Scapal basin deep and punctate; small, median punctures partially fused forming transverse striae, and with distinct oval facial pit ( Fig. 9 ). Brow prominent, TFC single, slightly convex, with traces of second carina. Brow raised between TFC and scapal basin. Brow above TFC flattened, with dense punctures. BOL 1.4 × MOD. Relative length of P:F1:F2:F3=1.2:2.2:1.3:1.0; F1 l/w=2.9; OOL 2.1 × MOD; POL 2.0 × MOD; MS 1.1 × MOD; clypeal apex arcuate medially. Mandible simple, without subapical tooth. Malar space with dense medium-sized punctures, and with genal carina reaching up to 2/3 of head height. Setae on vertex whitish, some of them longer than 1 × MOD. Ocellar triangle obtuse ( Fig. 10 ).

Mesosoma. Median pronotal line moderately deep, not extending to posterior margin of pronotum. Sublateral, longitudinal carina on pronotum fully developed ( Figs 8, 12 ). Punctation on pronotum, mesoscutum and mesoscutellum with variable interstices, 0.2–0.5 × PD; interstices shining and punctate ( Fig. 11 ). Mesepisternum with large punctures, interstices narrow, 0.1–0.5 × PD. Episternal sulcus and especially scrobal sulcus with large areolate punctures, about 2.0 × as large as punctures on mesepisternum ( Fig. 8 ). Setae on outer edge of metatibia short, not longer than half their distal width.

Metasoma. Metasoma densely punctate; punctures smaller than on mesosoma. Interstices on T1 and T2 0.2–1.0 × PD, polished, almost smooth, with scattered tiny punctures. T1 with short median groove anteriorly, T2 with distinct median carina, reaching posterior margin ( Fig. 14 ). T3 punctate and medially wrinkled ( Fig. 14 ); prepit bulge slightly convex ( Fig. 15 ); pits large, apical rim wrinkled ( Fig. 14 ). Median tooth on apex of T3 sharp and pointed, lateral teeth shorter ( Fig. 14 ). Interval between median tooth and lateral tooth slightly wavy curved. S2 black spots triangular, fused medially, forming black mark twice wider than its length ( Fig. 13 ).

Colouration. Body metallic golden green, with blue reflections on pronotum, mesoscutum, mesoscutellum, metanotum and laterally on mesosoma. Terga golden green. Median blue spot on mesoscutellum large. Ocellar triangle with dark brownish interstices. Scape metallic green, dorsal part of pedicel metallic copper, rest of flagellum black. Tegula predominantly metallic blue, outer margin partly brownish-black. Wings slightly dimmed. Legs metallic bright green, basitarsi greenish, rest of tarsi blackish.

Male. Unknown.

Distribution. North-eastern Vietnam, Cao Bang Province.

Remarks. Trichrysis striata sp. nov. is similar to T. tonkinensis but it is differentiated by the following characters: large blue spot medially on mesoscutellum (vs. small spot medially on mesoscutum, not on mesoscutellum in T. tonkinensis ); interval between median and lateral tooth slightly waved (vs. fully incurved); S2 black spots triangular, fused medially (vs. versus S2 black spots almost trapezoid, fused medially in T. tonkinensis ).

Figures

FIGURES 8–12. Trichrysis striata sp. nov., holotype (female). 8. Habitus, lateral view. 9. Head, frontal view. 10. Head, dorsal view. 11. Mesoscutellum, metanotum and metapectal-propodeal disc, posterior view. 12. Head and mesosoma, dorsal view. Scale bar = 1 mm.

FIGURES 13–15. Trichrysis striata sp. nov., holotype (female)—continued. 13. S2, ventral view. 14. T2 and T3, dorsal view. 15. T2 and T3, lateral view. Scale bar = 0.5 mm (Fig. 13); 1 mm (Figs 14, 15).