Bibio enterodelus Unger, 1841

Skartveit, John & Krizmanić, Katarina, 2020, Revision of fossil Bibionidae (Insecta: Diptera) from the Miocene of Radoboj, Croatia, Zootaxa 4759 (3), pp. 351-378 : 362

Bibio enterodelus Unger, 1841

( Figs. 9–10 , 28–30 )

Bibio enterodelus Unger, 1841: 428 .

Bibio lividus Heer, 1849: 223 . Syn.n.

Type material: Holotype Bibio enterodelus (female) ( SLJG 77425). Heer mentioned just a single specimen of Bibio enterodelus . Holotype Bibio lividus (female) ( GBA 2009/016/0691). Heer (1849: 224) mentioned one specimen from “Cabinet zu Wien” which is currently in GBA.

Additional material: One female ( CNHM 1838).

Description

Male unknown.

Female: Total length 15.0– 15.2 mm (N=2).

Head ( Fig. 29 ): Length 1.7 mm (N=2). Brown. Antenna rather slender. Ocellar tubercle prominent.

Thorax: Length 5.1 mm (N=1). Brown, probably faded colour. Halter light brown.

Wing ( Fig. 28 ): Length 12.3–12.7 mm (N=3), width 4.0– 4.4 mm (N=3). Light brownish, veins apparently concolourous with membrane. Relatively slender. Veins rather strong and prominent. Basal R s 1.6 –2.0* as long as R-M. Fork of M relatively short, M-veins apically straight. Crossvein Bm-Cu meets M 2 slightly beyond fork of M. CuA 2 apically strongly curved. Vein measurements (N=3): Subcosta 6.3–6.6 mm, basal R 3.8–4.9 mm, distal R 1 2.4–2.6 mm, basal R s 1.1 –1.5 mm, distal R s (=R 2–5) 5.4–6.0 mm, R-M 0.4–0.8 mm, basal M 3.7–4.6 mm, distal M 0.8–1.0 mm, M 1 4.5–4.9 mm, M 2 3.6–3.8 mm, M-Cu 0.6–1.2 mm, CuA 2.4–2.8 mm, CuA 1 4.5–5.7 mm, CuA 2 3.3–4.5 mm.

Legs: Fore femur ( Fig. 29 ) length 3.1 mm, width 0.8 mm (N=1). Hind femur ( Fig. 30 ) length 4.0– 4.7 mm, width 0.8–0.9 mm (N=2), hind tibia length 4.5 mm, width 0.5 mm (N=1).

Abdomen: Length 9.7–12.0 mm (N=2), width 3.6 mm (N=1). Pale brown, cylindrical.

Discussion: The holotype specimen of Bibio lividus is rather uniformly brown except that the tibiae are darker, not coloured like the recent species Bibio hortulanus as claimed by Heer (1849: 223). The colour is unlikely to be original.

Figures

FIGURE 9. Bibio enterodelus, female, holotype, SLJG 77425.

FIGURE 10. Bibio enterodelus, female, holotype of Bibio lividus, GBA 2009/016/0691.

FIGURES 26–28. 26. Plecia lugubris, possible type, female, wing (somewhat shortened), NHMW, no catalog number. 27. Plecia lygaeoides, female, holotype, wing, SLJG 77465. 28. Bibio enterodelus, female, holotype, wing, SLJG 77425. Scale bar = 1 mm.

FIGURES 29–31. 29. Bibio enterodelus, female, holotype of Bibio lividus, head and fore leg. GBA 2009/016/0691. 30. Bibio enterodelus, female, holotype of Bibio lividus, hind leg. GBA 2009/016/0691. 31. Bibio firmus, holotype, female, wing, SLJG 77471. Wing venation is highly tentative. Scale bar = 1 mm.