Istiochrysis ziliolii Rosa, Feng & Xu

Rosa, Paolo, Feng, Jun & Xu, Zai-Fu, 2016, Istiochrysis gen. nov., a new chrysidid genus from Oriental China (Hymenoptera, Chrysididae), Zootaxa 4111 (5), pp. 591-597 : 596

Istiochrysis ziliolii Rosa, Feng & Xu , sp. nov.

( Figs 1A–1 C, 2A–2D, 3A–3B, 4A–4F)

Material examined. Holotype, ♂, China: Yunnan, Tengchong, Qushi (25°13'51''N 98°36'36''E), 1–9.VIII.2011, J-j Chen [ SCAU]. Paratype: 1♂, China: Yunnan, Gaoligongshan National Nature Reserve (25°50'23''N 98°51'23''E), 1–18.VIII.2005, J-j Ma & Y-l Cai [ SCAU].

Diagnosis. Istiochrysis ziliolii sp. nov. is the only known species within this genus. It can be recognised by apex of T3 simple, without teeth and somehow bilobate; metanotum with raised subtriangular median area, shallowly concave medially; black spots on S2 large and connected to lateral margins; genital capsula with crestate aedeagus.

Description. Male. Holotype. Body length 5.0 mm ( Fig. 4A ).

Head. Scapal basin transversally microridged ( Fig. 4 B); scapal basin with white setae, especially along lateral sides. TFC convex, topping scapal basin ending about 1 MOD from ocular margin (about to eye margin in paratype); TFC without posterior branches. Relative length of P:F1:F2:F3=1.0:1.3:0.8:0.7; F1 l/w> 3; OOL=2 MOD; POL=2.5 MOD; BOL=2.0 MOD; MS=1.0 MOD; subantennal space 0.5 MOD. Clypeus not incised medially.

Mesosoma . Pronotal groove deep, almost reaching posterior margin. Pronotum, mesoscutum and mesoscutellum with large foveate punctures. Postero-lateral corners of mesoscutum, distinctly depressed over tegulae. Parapsidal furrows distinct. Antero-lateral margins of mesoscutellum elongate and upwardly directed. Mesopleuron somewhat bulging over the large and scrobiculate episternal and scrobal sulci. Metanotum with raised subtriangular median area, shallowly concave medially ( Figs 2 C, 2D) and elevated along its margins.

Metasoma. T1, T2 and T3 with geminate, small and dense punctures, almost without interspaces between punctures; punctures with smaller diameter along posterior margin and median longitudinal carina ( Fig. 4 E). T3 with row of large pits. Apex of T3 simple, somewhat bilobate apically. Black spots on S2 large, subrectangular and connected to lateral margins ( Fig. 3 B).

Colouration. Body blue, with dark blue areas dorsally on metasoma. Clypeus and lower part of face metallic green with golden reflections. Scape, pedicel and F1 metallic green with golden reflections; rest of flagellum black. Tegula metallic blue. Legs with coxae, trochanters, femora and tibiae metallic blue, and tarsi black. Sterna metallic green to blue. Head and mesosoma with grey to blackish long (up to 2 MOD) setae. Metasoma with grey to whitish long (up to 2 MOD) setae.

Female. Unknown.

Distribution. China (Yunnan).

Etymology. The specific name ziliolii is named after Michele Zilioli, well known entomologist, who provided the SEM pictures for this study, as well as other pictures for our research on Chinese Chrysididae .

Figures

FIGURE 1 A – 1 F. Genitalia. A – C. Istiochrysis ziliolii sp. nov., A, dorsal view; B, dorso-lateral view; C, lateral view; D. Trichrysis cyanea (Linnaeus), dorsal view; E. Chrysidea pumila (Klug), dorsal view; F. Caenochrysis doriae (Gribodo), dorsal view.

FIGURE 4 A – 4 F. Istiochrysis ziliolii sp. nov., holotype, ♂. A. Habitus, lateral view; B. Head, frontal view; C. Mesosoma, dorsal view, arrow pointing to the metanotal concave medial area; D. Mesopleuron, lateral view; E. Metasoma, dorsal view; F. T 3, posterior view.

FIGURE 2 A – 2 D. Head of Istiochrysis gen. nov. A. Head, frontal view, arrow pointing to the shallow micropunctate and densely setose depression; B. Detail of the depression between clypeus and lower margin of eye by SEM; C. Metanotum with raised triangular median area, which is shallowly concave medially; D. Detail of the raised median area on metanotum by SEM.

FIGURE 3 A – 3 D. A. Fore wing of Istiochrysis gen. nov.. B. S 2 black spots of Istiochrysis gen. nov.; C. S 2 black spots of Trichrysis Lichtenstein; D. S 2 black spots of Caenochrysis Bohart & Kimsey or Chrysidea Bischoff.