Chelonus (Microchelonus) scirpophagae Zhou & Achterberg & Tang & Chen 2024, sp. nov.
Creators: name: Zhou, Jin-Jin
name: Achterberg, Cornelis Van
name: Tang, Pu
name: Chen, Xue-Xin
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Braconidae
Chelonus
Chelonus scirpophagae

description: Chelonus (Microchelonus) scirpophagae sp. nov.
Figs 71–72
Material examined. Holotype: male, Guixian County, Guangxi Prov., China, 1.X.1979, Zhihong Zhou, No. 821370 (ZJUH). Excluded from type series: 1 male, Yuanmou Yunnan Prov., China, 1.IV.1980, Jiasheng Gan, No. 814233, reared from Scirpophaga incertulas.
Diagnosis. This new species is similar to the male of C. (M.) clivus sp. nov. (Fig. 21), sharing the carapace with a large yellowish spot medio-basally and carapace widest after middle in dorsal view, but the two species can be separated by the following characters: apical aperture in posterior view very large, the upper corner of carapace triangularly projecting (Fig. 72F) (versus apical aperture oval and carapace without any projection dorso-apically in C. (M.) clivus (Fig. 22F)); face smooth and very shiny (Fig. 72G, holotype) or very finely reticulate-rugulose in reared specimen (versus transverse-longitudinally striate-rugose (Fig. 22G)); temples distinctly widened behind eyes (Fig. 22H) (versus narrowed (Fig. 22H)).
Description. Holotype, male, length of body 5.1 mm, of fore wing 3.8 mm.
Head. Head transverse, width of head 1.7 × its dorsal length; occiput hardly excavated; antenna largely missing; eye 1.6 × as long as temple in dorsal view; OOL: OD: POL=25: 11: 11; temple strongly narrowed behind eyes; frons and vertex smooth and shiny (Fig. 72H); face flat, smooth and shiny, width of face 1.6 × its height; eyes slightly diverging; clypeus smooth and extending far above lower level of eyes, interspaces shiny, apical margin convex medially, clypeus 1.5 × wider than high, distance between tentorial pits 1.9 × distance between pits and eyes (Fig. 72G).
Mesosoma. Length of mesosoma 1.5 × its height; side of pronotum sparsely punctate; mesopleuron completely coarsely reticulate-rugose (Fig. 72B); notauli slightly impressed, mesoscutum densely alveolate-rugose; scutellum rugulose; scutellar suture comparatively deep, with short carinae; propodeum coarsely rugose, tubercles small and acute (Fig. 72C).
Wings. Vein r somewhat arched; length of marginal cell 0.7 × as long as pterostigma; pterostigma length 3.6 × its width; r: 3-SR: SR1=14: 22: 66; SR1 slightly sinuate; marginal cell 1.7 × longer than submarginal cell; 1-CU1: 2-CU1= 26: 54 (Figs 72A).
Legs. Hind coxa punctate; length of hind femur, tibia and basitarsus 3.1 ×, 5.4 × and 6.0 × their maximum width, respectively; length of inner hind tibial spur 0.5 × hind basitarsus.
Metasoma. Length of carapace 2.0 × its maximum width, widest after middle and apical fifth distinctly narrowed; basal half of carapace reticulate-rugose up to middle, densely punctate apically (Fig. 72E); carapace in lateral view 2.8 × longer than high, posterior height of metasoma 1.8 × its anterior height, carapace apically distinctly incurved (Fig. 72D); apical aperture in posterior view very large and 2.4 × wider than high, elongate, broadly slit-shaped, in lateral view wide triangular up to apical 1/4 metasoma (Fig. 72D), upper corner of carapace triangularly projecting (Fig. 72F).
Colour. Black; palpi brown; pterostigma and parastigma dark brown, wing and its veins dark brown, legs dark brown, but fore femur brown; metasomal carapace with yellowish band but corners black.
Female. Unknown.
Variation. Face of non-type specimen very finely reticulate-rugose and with satin sheen; frons and vertex very finely transversely rugose, occiput slightly excavated.
Biology. Solitary ovo-larval parasitoid of the rice yellow stem borer or Scirpophaga incertulas (Walker, 1863) (Lepidoptera, Crambidae). The biology of the reared specimen is mentioned in the publication “Identification of Natural Enemies of Rice Pests in Yunnan ” published in 1986, where this species was included as Chelonus sp. It is the first record of a Chelonus species as parasitoid of this host.
Distribution. China (Guangxi, Yunnan).
Etymology. The name refers to the genus of its host.
description: Published as part of Zhou, Jin-Jin, Achterberg, Cornelis Van, Tang, Pu & Chen, Xue-Xin, 2024, A review of the subgenera Carinichelonus, Microchelonus, Parachelonus and Stylochelonus of the genus Chelonus Panzer (Braconidae: Cheloninae) with descriptions of twenty-one new species from China, pp. 1-127 in Zootaxa 5412 (1) on pages 81-83, DOI: 10.11646/zootaxa.5412.1.1, http://zenodo.org/record/10675974