Chrysidea rioae,

Mita, Toshiharu & Rosa, Paolo, 2019, Redescription of Chrysidea pumiloides Zimmermann, 1956, and description of three new species of Chrysidea from Madagascar (Hymenoptera: Chrysididae), European Journal of Taxonomy 564, pp. 1-20: 14-17

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Chrysidea rioae

sp. nov.

Chrysidea rioae  sp. nov.

Figs 8View Fig, 9DView Fig


Chrysidea rioae  sp. nov. is characterized by the combination of the following characters: TFC absent; head narrow, 1.8 × as wide as high; distal margin of T3 with large, triangular lateral teeth and area between faintly concave medially; MS 1.2 MOD; tegula metallic blue; second metasomal tergum with interspaces among punctures microreticulate; paramere narrowed, triangular; aedeagus wide, laterally not expanded.


The specimen was collected during the field trip in Madagascar from January to February 2018. After that, the holotype was displayed at the summer exhibition of the National Museum of Nature and Science, Tokyo, Japan from July to October 2018. The species is named after Ms Rio Matsushima, a girl who visited the exhibition and heartily encouraged our study on this tiny blue wasp.

Material examined


MADAGASCAR • ♂; “ Madagascar : Anosy, Berenty Reserve, 40 m alt., 25°00′28.7″ S, 46°18′27.3″ E, 7–12. II. 2018, Yellow pan trap, T. Mita leg.”; “ Holotype ♂ / Chrysidea rioae Mita & Rosa, 2019  ”; ELKU.GoogleMaps 



BODY LENGTH. 3.8 mm.

HEAD. Width 1.8 × as wide as high. Scapal basin deep, transversely wrinkled and punctate with sparsely located minute punctures. TFC absent ( Fig. 8BView Fig). Antennomeres P, F1, F2, F3: 1.2: 1.3: 1.2: 0.8; F1 l/w = 1.6; OOL = 1.7 MOD; POL = 2.0 MOD; MS = 1.2 MOD; apical margin of clypeus almost straight, faintly concave; mandible edentate, basally with a deep notch; basal width of mandible = 1.0 MOD. Brow with large, irregular and contiguous foveate punctures; PD on brow: 0.3–0.6 MOD ( Fig. 8BView Fig).

MESOSOMA. Pronotal groove shallow, extending ⁴⁄₅ length of pronotum. Sublateral carina indistinct. Notauli deep, complete; parapsidal lines indicated by smooth strip. Mesoscutellum humped. Metanotum humped ( Fig. 8CView Fig), separated from mesoscutellum by deep furrow, large anteromedian pit present but shallow as other marginal punctures ( Fig. 8DView Fig). Mesosoma entirely punctate by deep, coarse and irregularly sized punctures; pronotum and mesoscutum with densely located, large and fewer small punctures: largest punctures 0.5 MOD; punctures on mesoscutellum sparser than those on mesoscutum, with smooth interspaces. Episternal sulcus indicated by shallow depression; scrobal sulcus formed by a row of deep and large foveae. Forewing with discoidal cell framed by nebulous veins, outer veins almost invisible ( Fig. 8AView Fig).

METASOMA. Median carina faint on terga ( Fig. 8EView Fig). Punctures on T1 0.3–0.4 MOD, densely located each other, with smooth interspaces; punctures on T2 and T3 smaller, 0.2–0.3 MOD, with interspaces faintly microreticulate; pre-pit row area of T3 not bulged; pit row distinct, with large and deep pits. Apex of T3 ( Fig. 8GView Fig) with a pair of lateral dully teeth, interval between teeth rounded, faintly concave medially. S2 black spots ( Fig. 8FView Fig) transverse, oval and medially separated by 0.8 MOD. Distal apex of paramere narrowed, triangular ( Fig. 9DView Fig); aedeagus wide, laterally not expanded ( Fig. 9DView Fig).

COLORATION. Head metallic blue, around ocellar region blackish. Clypeus partly greenish. Antenna black with scape, pedicel and F1 metallic blue. Mandible black, basal margin metallic blue, distal half brown. Mesosoma metallic blue, with mesoscutum between notauli blackish. Tegula metallic blue. Legs metallic blue, with dark brown tarsi. T1 metallic blue, T2 black with violet luster except posterior margin metallic blue; T3 basally blackish, apically metallic blue, with violet luster. Sterna dark metallic blue.




Southern Madagascar (Anosy).




The holotype was collected in a yellow pan trap set in the dry forest along the Mandrare River. Chrysidea rioae  sp. nov. is similar to C. pumiloides  , in the smaller body size, the general habitus and the microreticulation on the second metasomal tergum; however, in C. rioae  sp. nov. the base of punctures on the mesosoma is deep and rounded ( Fig. 8DView Fig); the metanotum is humped ( Fig. 8CView Fig) and a large anteromedian pit is present; the distal apex of paramere is narrowed ( Fig. 9DView Fig). In C. pumiloides  , the base of punctures is shallow and flat ( Figs 1CView Fig, 2CView Fig), the metanotum is rounded ( Fig. 1AView Fig), the anteromedian pit is absent, and the distal apex of the paramere is flat ( Fig. 9AView Fig).