Ichneumon cavigena, Riedel, 2019

Riedel, Matthias, 2019, Contribution to the Ichneumoninae (Hymenoptera, Ichneumonidae) of Nepal, Linzer biologische Beiträge 51 (2), pp. 1119-1162 : 1133-1135

Ichneumon cavigena nov.sp. ( figs 26-27 )

Holotype: ♀ "Westnepal Triurakot, 2050, 29°01´03´´N 82°47´35´´E, 31.05.1997, leg. Creutzburg " ( SDEI).

Paratype: ♂ " Nepal: Surkhet distr., 1600-2000 m, 28.V.1998, leg. G. Miksch " ( ZSM).

D e s c r i p t i o n: ♀: Body length 11 mm. Flagellum stout, slightly lanceolate, with 37 flagellomeres; 1 st flagellomere 1.4x longer than wide, c. 4 th flagellomere square; widest flagellomeres 1.6x wider than long; preapical flagellomere 0.9x as long as wide. Temple moderately and roundly narrowed behind eye, dorsally 0.8x as long as eye. Distance of lateral ocellus to eye 1.3x ocellar diameter. Frons and vertex coarsely rugose-punctate. Face densely punctate, partly with transverse rugae; facial orbit with scattered punctures. Clypeus and gena with dense punctures. Malar space 0.9x as long as width of mandibular base. Mandible stout and slightly swollen; upper tooth long and blunt, lower tooth very small and only indicated as a small ridge at ventral margin of upper tooth. Genal carina reaching hypostomal carina far from mandibular base; hypostomal carina lamelliform widened, about 2x wider than distal maxillary palp.

Mesosoma coarsely rugose-punctate, covered with short brownish hairs. Notaulus impressed at frontal margin of mesoscutum. Mesoscutum densely rugose-punctate. Mesopleuron and metapleuron coarsely rugose; speculum smooth, with fine scattered punctures. Juxtacoxal carina indistinct. Scutellum flat, 1.4x wider than long, with rather dense punctures, without lateral carina. Propodeum coarsely rugulose-punctate. Area superomedia slightly longer than wide, about rectangular; costula absent. Hind coxa densely punctate, with weak scopa indicated by a short brush of dense hairs. Hind femur densely punctate, 3.1x longer than wide. Claws not pectinate.

Areolet pentagonal, frontal distance of intercubiti c. 3x their width; 2 nd recurrent vein strongly distal to its middle. Nervulus postfurcal.

Metasoma stout, oxypygous. Postpetiolus strongly widened apically, with fine dorsal carina. Lateral field c. 0.7x as wide as median one; both fields with fine dense aciculation. Gastrocoelus distinctly impressed and with fine ridges. Thyridium slightly oblique, c. 0.8x as wide as the interval. 2 nd tergite 1.4x wider than long. 2 nd and 3 rd tergites with dense fine rugose punctures, not distinctly aciculate medially.

Colour: Black. Antenna tricoloured; scape, pedicle and flagellomeres 1-7 orange; flagellomeres 8-13 yellowish, following flagellomeres black. Mandible, palps, clypeus except blackish apical margin, face, ventral gena, hind edge of pronotum, tegula, 1 st tergite, apical margin of 4 th tergite, complete 5 th to 7 th tergites and legs (except narrow black basal margin of hind coxa) reddish. Frontal orbit and collare yellowish-red. Subtegular ridge, scutellum and wide apical bands of 1 st to 3 rd tergites yellow. Wings with brownish

tint, pterostigma pale ochreous. ♂: Body length 16 mm. Flagellum bristle-shaped, with 42 flagellomeres; 1st flagellomere

2.1x longer than wide. Tyloids on flagellomeres 6-20, linear, situated in basal 0.7 of flagellomeres. Temple strongly and almost linearly narrowed behind eye, dorsally 1.0x as long as eye. Occiput medially with transverse impression in front of occipital carina. Distance of lateral ocellus to eye 1.3x ocellar diameter. Frons and vertex coarsely rugose-punctate. Face and clypeus densely punctate. Mandible with two teeth; lower tooth smaller than upper one. Malar space 1.0x as long as width of mandibular base. Genal carina absent ventrally, gena concavely excised ventrally; hypostomal carina strongly and lamelliform widened (by 1/2x width of mandibular base), about 2x wider than distal maxillary palp.

Mesosoma covered with grey hairs. Notaulus impressed at frontal margin of mesoscutum. Mesoscutum densely rugose-punctate, but shining. Mesopleuron densely and coarsely punctate, speculum with finer dense punctures. Metapleuron coarsely rugosepunctate; juxtacoxal carina partly indistinct. Scutellum moderately elevated, 1.3x wider than long, with dense punctures, without lateral carina. Area superomedia hexagonal, 1.1x wider than long, rugose; costula weak, reaching area superomedia at its basal 0.4. Area externa punctate. Area petiolaris rugose, lateral carina indistinct. Hind coxa densely punctate. Hind femur densely punctate, 3.5x longer than wide. Fore metatarsus without

apical tooth. Areolet pentagonal, frontal distance of intercubiti c. 4x their width; 2nd recurrent vein in

its middle. Nervulus postfurcal (2x its width).

Postpetiolus strongly widened apically. Lateral field about as wide as median one, punctate; median field elevated, coarsely and longitudinally rugose-punctate. Gastro-coelus strongly impressed and with longitudinal ridges. Thyridium transverse, 0.9x as wide as the interval. 2 nd tergite 1.2x wider than long. 2 nd to 4 th tergites densely and coarsely rugose-punctate; 2 nd tergite with longitudinal rugae between gastrocoeli. 2 nd to 4 th sternites with median folds.

Colour: Black. Flagellum black dorsally and reddish ventrally. Clypeus except narrow black apical margin, face and ventral spot on scape yellow. Collare, tegula, subtegular ridge and scutellum yellow. 1 st to 3 rd tergites with wide yellowish apical bands (which are more reddish in their frontal third). 4 th tergite with narrow apical reddish-yellow band. 5 th tergite laterally and at apical third and 6 th and 7 th tergites completely red. Coxae and trochanters black; small spots on fore and mid coxae and apical margins of fore and mid trochanters yellowish; legs otherwise red; hind femur and hind tibia in their apical 0.2 black. Wings with slighty yellowish tint, pterostigma yellow.

R e m a r k: This new species is characterized by the lamelliform hypostomal carina and colouration of metasoma in both sexes and the ventrally excavated gena in ♂ (similar to some ♂♂ of Ichneumon tuberculipes WESMAEL).

Figures

Figs 26-29: Habitus from dorsal: (26) Ichneumon cavigena nov.sp. ♀, (27) Ichneumon cavigena nov.sp. ♂, (28) Ichneumon creutzburgi nov.sp. ♀, (29) Ichneumon longigenalis nov.sp. ♀.