Epirhyssa overlaeti Seyrig, 1937

Rousse, Pascal & Noort, Simon Van, 2014, A review of the Afrotropical Rhyssinae (Hymenoptera: Ichneumonidae) with the descriptions of five new species, European Journal of Taxonomy 91, pp. 1-42 : 26-28

Epirhyssa overlaeti Seyrig, 1937

Fig. 7

Diagnosis

Overall color mottled, black, yellow and testaceous; wings hyaline, slightly infuscate apically; face transversely striate, nearly flat; clypeus shallowly and sparsely punctate, without subapical tubercle, ventral margin strongly produced laterally; frons smooth, with a sharp mid-longitudinal carina reaching median ocellus and lateral curved carina toward lateral ocellus; antenna with 41–43 flagellomeres; epicnemial carina reaching lower level of speculum; fore wing with 2m–cu opposite rs–m; tergite 1 slender; all tergites nearly to quite smooth, tergites 4–5 finely transversely striate basally; apical margins of tergites 3–6 strongly concave. CT 2.5; ML 0.5; POL 1.3; OOL 1.6; Fl 1 3.9; Fl 15 2.8; Fl 42 1.3; T1 1.7; OT 7.2.

Differential diagnosis

Highly distinctive species of mottled color and large to very large size; otherwise characterized by the combination of the flat and sparsely punctate face, the sharp mid-longitudinal carina on the frons, the absence of a subapical ridge on the clypeus, and the very long ovipositor. No other known Epirhyssa species shares this color pattern.

Material examined

Holotype

DEMOCRATIC REPUBLIC OF CONGO: ♀, Lulua [10°37’ S 24°54’ E], Kapanga, Apr. 1933, F. G. Overlaet, R. Dét. F 3330 ( MRAC).

Other material

CAMEROON: 1 ♀, Nkoemvon, Jul.-Aug. 1980, Ms. D. Jackson ( BMNH).

Description

Female (2 specimens)

B 25.2–37.8; A 15.4–23.2; F 16.1–24.2.

COLOR. Head yellow with mandible black and lower gena, vertex and upper occiput brownish testaceous; mesosoma black to dark brownish testaceous interspersed with yellow markings: pronotum dorsally and ventrally, mesopleuron anteriorly and posteriorly, and mesoscutum, scutellum, metanotum and propodeum centrally; legs testaceous to dark testaceous with fore and mid coxa yellow; metasoma light to dark testaceous, tergites 1–5 with apico-lateral large yellow spots; antenna and ovipositor sheath dark brown; wings nearly hyaline, apically infuscate, venation dark brown.

HEAD. Face subquadrate, transversely striate and hardly bulging medially; clypeus shallowly and sparsely punctate, without subapical tubercle, ventral margin strongly produced laterally; mandible stout; upper head quite smooth; inner margins of toruli expanded backwards into two converging lamellar carinae, carinae then fused into a sharp mid-longitudinal carina reaching median ocellus; frons also with an additional lateral curved carina from posterior margin of torulus to next to lateral ocellus; occipital carina mid-dorsally interrupted; antenna with 41–43 flagellomeres.

MESOSOMA. Mesosoma shallowly and moderately densely punctate, but mesonotum transversely striate and anterior half of pronotum smooth; epomia indistinct; epicnemial carina reaching lower level of speculum, mesopleural pit indistinct; apex of subtegular ridge convex, not flanged laterally; submetapleural carina moderate and even all along.

WINGS. Fore wing with 2m–cu opposite rs–m, cu–a slightly apical to Rs&M, and Rs short and moderately bowed forwards; hind wing with distal abscissa of Cu joining Cu&cu–a at junction with M.

METASOMA. Tergite 1 moderately slender; all tergites smooth to indistinctly sculptured but tergites 4–5 weakly striate basally; apical margins of tergites 3–6 strongly concave, others straight.

Male

Unknown.

Distribution

Democratic Republic of Congo. New record: Cameroon.

Comments

The species is only known from two female specimens. They exhibit a remarkable variation in size, the BMNH specimen being one third smaller than the impressively large MRAC holotype.

Figures

Fig. 7. Epirhyssa overlaeti Seyrig, 1937, holotype, ♀. A. Habitus, lateral view (inset: data labels). B. Mesosoma, lateral view. C. Metasoma, dorsal view. D. Head, anterior view. E. Mandibles, anterior view.