Revision of fossil Bibionidae (Insecta: Diptera) from the Miocene of Radoboj, Croatia Author Skartveit, John Author Krizmanić, Katarina text Zootaxa 2020 2020-04-03 4759 3 351 378 journal article 10.11646/zootaxa.4759.3.3 9675f3d4-930d-4e4c-97e1-bcc7e6c5120d 1175-5326 3741178 FBD53C14-07AA-4E01-9739-214680A1DE4C Key to the fossil Bibionidae from Radoboj (females except for Penthetria cimicoides , Penthetria gracilis and Penthetria longa ). Species described from other localities which have unconfirmed records from Radoboj are included. 1 Radial sector furcate, distally divided with veins R 2+3 and R 4+5 . Crossvein R-M vertical. Legs slender................... 2 - Radial sector undivided. Crossvein R-M oblique. Legs more or less thickened ( Bibioninae )......................... 10 2 Vein R 2+3 long, more or less horizontal. (Genus Penthetria ).................................................... 3 - Vein R 2+3 short, oblique to vertical. (Genus Plecia )........................................................... 7 3 Wing wider, length/width = 2.6–2.7....................................................................... 4 - Wing narrower, length/width ≈ 3.0........................................................................ 5 4 Wing apically broadly rounded, R 2+3 very long and horizontal.................................. Penthetria cimicoides - Wing apically more pointed, R 2+3 shorter and more oblique...................................... Penthetria gracilis 5 Body and legs reddish brown...............................................................? Penthetria longa - Body and legs coal-black............................................................................... 6 6 R 2+3 longer, straight, wing apically more rounded........................................... Penthetria anthracina - R 2+3 shorter, distinctively curved, wing apically pointed...................................... Penthetria murchisonii 7 Very large species, body length ≈ 15 mm .......................................................... Plecia morio - Smaller species, body length 12 mm or less................................................................. 8 8 R 2+3 basally distinctively curved. Femorae mainly pale............................................ Plecia bucklandi - R 2+3 almost straight, legs entirely dark..................................................................... 9 9 Vein CuA 2 distally distinctively curved basad.................................................... Plecia lugubris - Vein CuA 2 distally nearly straight............................................................ Plecia lygaeoides 10 Fore tibia cylindrical, with spines mesally. Thorax anteriorly with two transverse spine rows. Body ochreous-brown with dark head................................................................................... Dilophus pinguis - Fore tibia spindle-shaped with apical spine. Thorax without spines. Body dark. (genus Bibio )........................ 11 11 Wing with radial area black, contrasting against the rest of wing. Very large species,> 15 mm ............ Bibio giganteus - Radial area of wing not darkened. Often markedly smaller species............................................. 12 12 Wing with Radial sector less than twice as long as R-M.............................................. Bibio firmus - Wing with Radial sector at least twice as long as crossvein R-M............................................... 13 13 Wing hyaline with dark veins and highly distinctive, dark pterostigma. Vein M 2 distinctively bent at junction with crossvein M-CuA................................................................................ Bibio crassinervis - Wing veins apparently concolourous with membrane, pterostigma indistinctive. Vein M 2 straight at junction with crossvein M- CuA................................................................................... Bibio enterodelus