Revision of fossil Bibionidae (Insecta: Diptera) from French Oligocene deposits Author Skartveit, John Author Nel, André text Zootaxa 2017 4225 1 1 83 journal article 37263 10.5281/zenodo.259087 05be601b-f9f1-4952-ac09-7012ef31aab0 1175-5326 259087 4676EE59-569B-4197-B108-9B32FD88E68E Genus Plecia Wiedemann, 1828 In the 19th Century, fossil Plecia species were mostly placed in the genus Protomyia Heer , though many Penthetria species were also included in this genus. Plecia assonensis Gentilini, 1993 ( Figs. 19 , 107 – 109 ) Plecia assonensis Gentilini 1993 : 161 . Possibly a synonym of Plecia livida , but the pointed gonostylus might be diagnostic together with the straight, oblique vein R2+3 and the indistinctive pterostigma. Material examined. (RGL) Dauphin 33, Bois d’Asson 34, Bois d’Asson 81 Localities. Bois d’Asson Diagnosis. A small Plecia (wing length approximately 5 mm ). Antennal flagellum 9-segmented. Vein R2+3 straight and oblique. Male gonostylus stout digitiform. Redescription. Male: Total length 5.0– 8.5 mm (N=2, the former specimen obviously shrunk) Head: Length 0.81 mm (N=1), width 0.86 – 1.21 mm (N=2). Antennal flagellum 9-segmented according to Gentilini (1993: 161) , not possible to see in the specimens at hand. Thorax: Length 1.7 – 2.9 mm (N=3), width 1.7 – 2.2 mm (N=2). Brown. Haltere pale. Wing (fig. 107): Length 5.1 – 5.7 mm (N=3), width 1.7 – 2.5 mm (N=2), length/width = 2.31 – 3.01 (N=2). Pale brownish, almost hyaline, veins brown, slender, R-veins not notably stronger than posterior veins. Costa extends to a little beyond apex of R4+5. Subcosta fine, terminates approximately at fork of M, humeral vein present. Vein R 2+3 short, nearly straight and oblique, R4+5 slightly curved. Pterostigma small, light brown, indistinctive. Wing vein measurements in Table 2. Legs: Light brownish, getting darker apicad. Hind femur apparently pale with darker apex. Abdomen: Length 2.9 – 5.8 mm (N=3), width 0.9 – 1.4 mm (N=3). Brown, relatively broad. Terminalia (figs. 108–109): Hypopygium 0.70 – 0.77 mm (N=3) wide, broad and robust. Gonostyli 0.35 – 0.46 mm (N=3), short, robust, apically pointed. Epandrium mesally with a shallow, V-shaped cleft. Female unknown. FIGURES 107–109. Plecia assonensis Gentilini, 1993 Fig. 107. Male, wing. RGL Dauphín 33. Fig. 108 . Male, terminalia, dorsal. RGFL Bois d’Asson 81. Fig. 109 . Male, terminalia. RGL Bois d’Asson 34.