Review of the genus Stenomacrus Förster, 1869 (Hymenoptera: Ichneumonidae: Orthocentrinae) from Kenya and Burundi: a first step to understanding the diversity of the genus in the Afrotropics Author Varga, Oleksandr text European Journal of Taxonomy 2024 2024-10-03 958 177 202 https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2669/12369 journal article 10.5852/ejt.2024.958.2669 2118-9773 13903208 0747183C-7180-494A-96CC-9A3DE3FAA019 Stenomacrus luteus sp. nov. urn:lsid:zoobank.org:act: 10545C32-556D-43B1-A7BA-B8EF561D4B0B Fig. 5 Diagnosis Stenomacrus luteus sp. nov. is characterized by the combination of the following: face smooth ( Fig. 5B ); mesosoma yellow ventrally ( Fig. 5A ); antenna with 18 flagellomeres, first flagellomere 3.3 × as long as wide; temples 0.4 × the maximum diameter of eye in dorsal view, strongly narrowed ( Fig. 5D ); propodeum smooth, weakly wrinkled subapically, with only area apicalis partly delimited by carinae ( Fig. 5E ); fore wing with vein 2 rs-m about 0.8 × the distance between 2 rs-m and 2 m-cu ; vein 3rs-m absent ( Fig. 5F ); first tergite 1.4 × as long as its apical width, longitudinally wrinkled, with latero-median longitudinal carinae hardly visible among wrinkles; second tergite 1.1 × as long as its apical width, sculptured on basal 0.3 ( Fig. 5G ); ovipositor sheath about 0.6 × as long as hind tibia ( Fig. 5A ). Stenomacrus luteus sp. nov. differs from all known Afrotropical species in having a largely yellow mesosoma in combination with a smooth face and relatively short antenna. Etymology The new species is named after the relatively pale yellowish body colouration. Type material Holotype KENYA • ♀ ; Eastern Prov. , Mt Kulal Forest ; 2.65400º N , 36.93660º E ; 1810 m a.s.l. ; 1 Nov. 2015 – 01 Apr. 2016 ; R . Copeland leg.; Malaise trap in disturbed forest; ICIPE . Paratype KENYA • 1 ♀ ; same data as for holotype; ICIPE . Description Female Body length 2.5 mm . Fore wing 1.9 mm . Head smooth and sparsely pubescent. Antenna with 18 flagellomeres, first flagellomere 3.3 × as long as wide. Face about 0.6 × as long as wide, smooth, sparsely pubescent; inner orbits parallel. Malar space 2.1 × basal width of mandible; subocular sulcus distinct. Clypeus 0.7 × as long as wide, smooth. Mandible bidentate, strongly bent outwards; lower tooth small and hardly visible. Temples 0.4 × maximum diameter of eye in dorsal view, strongly narrowed. Frons and vertex smooth; length of ocellar-ocular distance about as long as maximum diameter of lateral ocellus; occipital carina absent. Fig. 5. Stenomacrus luteus sp. nov. , holotype, ♀ (ICIPE). A . Lateral view of habitus. B . Frontal view of face. C . Lateral view of head and mesosoma. D . Dorsal view of head and mesoscutum. E . Dorsal view of propodeum. F . Wings. G . Dorsal view of metasomal tergites 1–3. Scale bars: A = 0.5 mm; B–G = 0.1 mm. Propleuron sparsely pubescent. Pronotum smooth; epomia absent. Mesoscutum densely pubescent anteriorly; notauli absent. Scutellum sparsely pubescent, with carinae present only on basal 0.1. Mesopleuron smooth; epicnemial carina present laterally. Metapleuron smooth; pleural and submetapleural carinae present. Propodeum smooth, weakly wrinkled apically, with only area apicalis partly delimited by carinae. Legs relatively stout; hind femur 3.5 × as long as wide, third tarsomere of hind tarsus about as long as fifth tarsomere; tarsal claws simple. Fore wing with vein 2 rs-m about 0.8 × distance between 2 rs-m and 2 m-cu ; vein 3rs-m absent; vein 1cu- a opposite M & Rs ; hind wing with nervellus not intercepted, reclivous. Metasoma with first tergite 1.4 × as long as apical width, smooth, longitudinally wrinkled, with latero-median longitudinal carinae hardly visible among wrinkles; lateral oblique grooves distinct and deep. Second tergite 1.1 × as long as apical width, sculptured on basal 0.3, with weak basolateral grooves; thyridium round. Remaining part of metasoma smooth, laterally compressed. Ovipositor sheath about 0.6 × as long as hind tibia, apical part widened and pubescent. Body generally brown dorsally and yellow ventrally: antenna, face narrowly below antennal sockets, mandible (except apices), mesosoma ventally, and legs yellow. Male Unknown. Distribution So far only known from Kenya .