Rugichneumon, Riedel, 2023

Riedel, Matthias, 2023, Notes on Ichneumoninae (Hymenoptera, Ichneumonidae) from southern China, with descriptions of one new genus and twelve new species, Contributions to Entomology 73 (2), pp. 223-248 : 223

Rugichneumon gen. nov.

Type species.

Rugichneumon tricolor sp. nov.

Etymology.

The name refers to the distinct reticulate-rugose anterior tergites of the type species.

Diagnosis.

Flagellum rather short and filiform in ♀, bristle-shaped in ♂. Tyloids in ♂ present, but indistinctly differentiated. Temple roundly narrowed behind eye. Temple and frons finely and densely punctate. Face punctate, shining. Clypeus moderately convex, 2.3 × as wide as long, punctate; apical margin sharp and almost straight. Mandible unmodified; ventral mandibular tooth smaller than upper tooth and slightly bent inwards. Malar space shorter than width of mandibular base. Genal carina reaching hypostomal carina far from mandibular base. Epomia absent. Notaulus weakly impressed at frontal margin of mesoscutum. Mesoscutum rugose-punctate, ± shining. Mesopleuron and metapleuron including speculum mainly rugose-punctate. Juxtacoxal carina present. Scutellum moderately convex, wider than long, with lateral carina on its anterior 0.7. Propodeum coarsely rugose-punctate, almost continuously sloping to apex, but area dentipara only slightly elongate; apophysis completely absent; spiracles oval. Area basalis not developed. Area superomedia heart-shaped, its anterior margin moderately bulging medially. Anterior transverse carina (costula) present. Hind coxa of ♀ without scopa. Hind femur rather slender. Tarsal claws simple. Areolet pentagonal. Ramellus absent. Vein 1cu-a postfurcal. Metasoma oxypygous. Base of petiole slightly wider than high in ♀, less distinct in ♂. Postpetiole distinctly widened, with strong latero-median carina; median field elevated, coarsely reticulate-rugose. Gastrocoelus distinctly impressed, with some rugae. Thyridium transverse, shorter than interval between thyridia. 2nd to 4th sternites with median folds. 2nd to 4th tergites coarsely rugose-punctate, ± dull. Hypopygium slightly elongate in ♀, its apical margin with a short median extension in ♂. Ovipositor sheath of ♀ slightly extending beyond metasomal apex.

Remark.

The new genus has an intermediate form of the propodeum: it is more or less gradually sloping posteriorly (as in Protichneumonini sensu Heinrich 1968b), but the area dentipara is not distinctly elongate (as in Ichneumonini sensu Heinrich 1968b). The area basalis is absent and only indicated by a median bulging of the area superomedia towards the postscutellum. The anterior tergites have a very coarse surface structure. The base of the petiolus is slightly wider than high (as in the tribe Platylabini ), but the new genus differs from members of Platylabini by several features, such as its unmodified mandible and oxypygous metasoma. The new genus is included in the tribe Ichneumonini sensu Santos et al. (2021) here. In the key to the Oriental genera of Ichneumoninae ( Townes et al. 1961), the new genus runs to Celebijoppa Heinrich, but differs by a different carination of the propodeum (distinctly dorsal and postero-dorsal faces which meet in a distinct angle in Celebijoppa ) and the very coarse reticulate surface structure of the anterior metasomal tergites.