Contribution to the knowledge of the Ichneumoninae (Hymenoptera, Ichneumonidae) from Maritime Southeast Asia Author Riedel, Matthias text Zootaxa 2023 2023-11-06 5363 1 1 94 https://www.mapress.com/zt/article/download/zootaxa.5363.1.1/52218 journal article 10.11646/zootaxa.5363.1.1 1175-5334 10146851 B8979382-355B-410A-B1C9-20AD910233E6 Achaius sabahensis nov. sp. ( Figs 2A–D ) Holotype . ( ♀ ) Malaysia : Sabah , Kinabalu Park Head Q. , 8–11.iii.1987 , c 1600 m , Malaise trap 1, C. van Achterberg , RMNH´87 (Leiden). Description . ♀ . Body length 10.5 mm . Head . Flagellum with 40 flagellomeres, slender, almost filiform; 1 st flagellomere 3.7 × longer than wide, widest flagellomeres 1.2 × longer than wider. Temple rather long, distinctly and linearly narrowed behind eye (fig. 2B). OED 1.0 × and OOD 1.1 × ocellar diameter. Frons smooth ventrally, transversely rugose-punctate dorsally. Face densely punctate, shining. Clypeus almost flat, with sparse punctures; apical margin sharp and slightly concave (fig. 2A). Mandible long, with two teeth, ventral tooth smaller than dorsal one. Malar space 1.2 × as long as width of mandibular base. Gena with sparse fine punctures. Genal carina reaching hypostomal carina away from mandibular base. FIGURE 2. Achaius sabahensis n. sp. HT ♀. A face, frontal view, B head, dorsal view, C propodeum, dorsal view, D basal tergites, dorsal view. Mesosoma . Side of pronotum densely punctate dorsally, with irregular rugae ventrally. Notaulus indistinct. Mesoscutum finely and densely punctate, slightly shining. Mesopleuron densely punctate and finely striate ventrally, densely punctate dorsally; speculum smooth. Metapleuron rugose-punctate; juxtacoxal carina present. Scutellum moderately elevated, about as long as wide, with fine sparse punctures; without lateral carina. Propodeum (fig. 2C) rugose, with distinct blunt apophysis; spiracle slit-shaped. Area basalis not carinated, without median tubercle. Area superomedia almost rectangular, 1.4 × longer than wide; costula absent. Hind coxa densely punctate, without scopa. Hind femur slender, densely punctate, 5.1 × longer than wide. Claws simple. Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 5 × their diameter. Vein 1cu-a postfurcal by 3.0 × its width. Metasoma . Strongly amblypygous; hypopygium unmodified, with fine setae, reaching metasomal apex. 2 nd and 3 rd sternites with median folds. Postpetiole moderately widened, without latero-median carina; median field moderately elevated, finely rugose; lateral field punctate. Gastrocoelus impressed, without ridges. Thyridium very small, oblique, 0.2 × as wide as the interval between thyridia (fig. 2D). 2 nd tergite as long as wide, finely rugose and slightly aciculate in basal half, granulate apically, ± dull. Following tergites finely granulate, shining. Ovipositor sheath not reaching behind metasomal apex. Colour . Black. Flagellum black; flagellomeres 8–12 brownish dorsally. Face and gena with dark reddish suffusion; frontal orbit with reddish-yellow stripe. Hind edge of pronotum, tegula, subtegular ridge, central spot of mesoscutum and scutellum reddish. Tergites dark reddish-brown; 7 th tergite with ivory median spot. Legs black; fore and mid femora and tibia reddish-yellow stripes frontally; hind tibia diffusely reddish-brown sub-basally. Wings hyaline; pterostigma blackish. ♁ unknown. Remarks . This new species runs to Achaius flavorufus Heinrich, 1965 in the key of the Oriental Achaius species ( Heinrich 1965: 111–112 ), but differs from all known Oriental species by the strong reduction of pale coloration. Distribution . Only known from Borneo.