Centistoides (Palaeoides) magnioculus Belokobylskij, 2024

Belokobylskij, Sergey A., Vasilenko, Dmitry V. & Perkovsky, Evgeny E., 2024, The first reliable fossil record of the tribe Centistini (Hymenoptera, Braconidae, Euphorinae): a new subgenus and species of braconid wasp in Danish amber, Journal of Hymenoptera Research 97, pp. 15-27 : 15

Centistoides (Palaeoides) magnioculus Belokobylskij sp. nov.

Figs 1 , 2

Type material.

Holotype: female, NHMD # 115540, with labels " Braconidae A.K. Andersen 28-3 /1968" and " Euphorinae ? huge ovipositor". Danish amber, late Eocene. Syninclusion: female of Chironomidae .

Description.

Female. Body length 3.8 mm; fore wing length 3.6 mm.

Head: Head rather short; occiput distinctly concave. Eye large, glabrous, ~ 1.4 times as high as broad (sublateral view); transverse diameter of eye almost 2.0 times longer than temple (subdorsal view). Ocelli medium-sized, convex, situated almost in equilateral triangle; POL approximately 0.8 times Od, 2.0 times OOL; Od ~ 2.2 times OOL. Face weakly convex, its width ~ 0.8 times mid-height. Clypeus distinctly convex, its width ~ 2.0 times mid-height, 0.8 times width of face. Malar space ~ 0.15 times height of eye, ~ 0.7 times basal width of mandible. Malar suture absent. Mandible distinctly twisted in apical half, with two apical teeth.

Antenna: Antenna long, almost filiform, 28-segmented, about as long as body. Scape 1.5 times longer than its maximum width, ~ 2.0 times longer than pedicel. First flagellar segment rather wide, 4.5 times longer than its maximum width, 1.2 times longer than second segment. Penultimate segment 1.5 times longer than its maximum width, 0.7 times as long as apical segment. Apical antennal segment with distinct distal spine.

Mesosoma: Mesosoma 1.2 times longer than its maximum height. Neck of prothorax short. Mesoscutum anteriorly distinctly convex and weakly protruding forward, without anterolateral corners. Notauli completely absent. Prescutellar depression (scutellar sulcus) rather short, densely crenulate. Scutellum short and weakly convex. Subalar depression shallow and narrow, smooth. Propodeum strongly curvedly narrowed posteriorly (lateral view).

Wings: Fore wing wide, 2.7 times longer than its maximum width. Pterostigma wide, 3.2 times longer than its width. Radial (marginal) cell distinctly shortened, 3.2 times longer than its maximum width. Metacarp (1-R1) 0.7 times as long as pterostigma. Radial vein (r) arising weakly behind middle of pterostigma. First (r) and second (3-RS+SR1) radial abscissae forming obtuse angle; first abscissa (r) 0.4 times as long as maximum width of pterostigma. Second radial abscissa (3-RS+SR1) evenly curved, almost 9.0 times longer than first abscissa (r), 2.7 times longer than first radiomedial vein (2-RS). Recurrent vein (m-cu) distinctly antefurcal, 2.0 times longer than second abscissa of medial vein (2-SR+M), 0.6 times as long as first radiomedial vein (2-RS), 0.45 times as long as basal vein (1-M). First abscissa of medial vein (1-SR+M) weakly sinuate. Discoidal (discal) cell 1.1 times longer than its maximum width. Nervulus (cu-a) 0.8 times as long as distance (1-CU1) between basal vein (1-M) and nervulus (cu-a). Parallel vein (CU1a) distinctly curved basally. Brachial (subdiscal) cell relatively short and rather wide. Hind wing ~ 4.5 times longer than its maximum width. Submedial (subbasal) cell long and wide; first abscissa of mediocubital vein (M+CU) ~ 4.0 times longer than second abscissa (1-M).

Legs: Fore femur wide, ~ 3.3 times longer than its maximum width. Fore tarsus shortened; tarsal segments mainly short. Hind coxa wide and short, massive, ~ 1.3 times longer than its maximum width. Hind femur ~ 4.0 times longer than its width. Hind tibia distinctly thickened. Hind tarsus shorter than hind tibia. Claw simple.

Metasoma: Metasoma curved down posteriorly, approximately as long as head and mesosoma combined. First metasomal tergite with distinct and complete dorsal carinae, approximately as long as propodeum. Second suture perhaps absent. Subposterior sternite with pair of short ventral teeth. Ovipositor wide, compressed and distinctly curved; dorsal valve of ovipositor apically without lobe. Ovipositor sheath rather thin (ventral view), short and wide, narrowed distally, with short apical tubercle (lateral view), covered by rather long and almost erect setae; sheath 2.2 times longer than its width, ~ 0.7 times as long as first tergite.

Sculpture: Body mainly smooth; sculpture of propodeum not visible, but perhaps with transverse carina.

Colour: Body dark brown to black. Palpi yellow. Antenna mainly black, brown basally. Legs mainly light reddish brown or reddish brown, hind tibia dark. Fore wing hyaline. Pterostigma entirely dark brown.

Male. Unknown.

Etymology.

This species is named after Latin “magnus” (large) and “oculus” (eye), because the eyes of the new species are distinctly enlarged.

Comparative diagnosis.

The new species differs from the type species of the genus Centistoides , C. doesburgi van Achterberg, 1992, primarily by subgeneric characters. The differences between all known species of Centistoides are shown in the key below.

Figures

Figure 1. Centistoides (Palaeoides) magnioculus sp. nov. (female, holotype, Danish amber, NHMD # 115540) A habitus, right dorso-lateral view B habitus, dorsal view C head and mesosoma, dorsal view D head and anterior part of mesosoma, dorso-lateral view E head, fronto-lateral view F metasoma and ovipositor, lateral view.

Figure 2. Centistoides (Palaeoides) magnioculus sp. nov. (female, holotype, Danish amber, NHMD # 115540) A wings, head and mesosoma, dorso-lateral view B fore wing C habitus, left sublateral view.