A Revision of fossil Bibionidae (Insecta: Diptera) from the Oligocene of Germany Author Skartveit, John 0000-0001-7614-3399 Author Wedmann, Sonja 0000-0002-9778-4125 edmann@senckenberg.de text Zootaxa 2021 2021-01-19 4909 1 1 77 journal article 8640 10.11646/zootaxa.4909.1.1 fa031765-b474-48aa-9d7e-b62dd092cfa4 1175-5326 4448697 92ECCF97-7315-4A1A-A94A-537D0F331EBF Plecia dubia ( Germar, 1837 ) (figs. 21–26, 108–113) Comb. n. Phthiria dubia Germar, 1837 Helophilus primarius Germar, 1837 Syn.n. Bibio dubius ( Germar, 1837 ) Giebel, 1856 Protomyia abava Heyden & Heyden, 1865: 20–21 . Syn.n. Plecia abava (Heyden & Heyden) Statz 1943: 12 . Syn.n. Plecia satyrus Statz, 1943: 12–13 . Syn.n. Localities : Orsberg, Enspel, Rott Material examined : Holotype (female) Phthiria dubia , STIPB A 595 (part and counterpart). Holotype (female) Helophilus primarius STIPB A 603. Syntype (male) Protomyia abava NHMUK In 58788, Syntype (female) Protomyia abava NHMUK In 58799. Syntypes Plecia satyrus LACMIP 2533 287 / LACMIP Type 3419, (female, part and counterpart), 2533.288 / LACMIP Type 3420 (female wing + abdomen, part and counterpart), 2533.289 / LACMIP Type 3421 (isolated wing), 2533.290 / LACMIP Type 3422 (isolated wing, part and counterpart). TABLE 4. Wing vein measurements, genus Plecia

Species, sex	Basal R	R 1	R s	R 2–5	R 2+3	R 4+5	R-M	Basal M	Dist. M	M 1	M 2	M-Cu	CuA	CuA 1	CuA 2
collossea Ƌ	3.78–3.83	3.93–4.22	2.10–2.23	1.84–1.99	0.97–1.18	2.94–3.41	0.51–0.53	4.55–4.78	0.46–0.62	4.03–4.14	2.84–2.92	0.38	3.32	4.34	2.84
collossea ♀	2.78–3.98	4.15–6.41	1.85–4.14	1.94–2.95	0.97–1.81	2.86–4.59	0.47–0.85	4.42–6.12	0.60–1.08	4.38–5.52	3.32–4.64	0.35–0.60	2.45–4.24	4.80–5.81	3.00–3.91
dubia ♂	2.63	4.29	0.61	–	1.14	0.33	2.76	2.80	2.19	2.49	3.94	2.63
dubia ♀	2.36–4.12	3.57–6.42	1.41–3.67	1.42–3.27	1.18–1.82	2.47–5.17	0.37–0.71	2.55–5.67	0.65–2.12	3.29–5.39	2.71–4.22	0.27–0.58	1.84–3.95	4.04–6.70	2.71–3.90
exigua ♂	1.04–1.63	1.35–1.82	0.58–0.87	0.65–1.00	0.33–0.50	1.00–1.32	0.21–0.31	1.42–2.19	0.25–0.38	1.43–2.04	1.08–1.63	0.16–0.25	0.95–1.28	1.46–2.38	0.96–1.42
exigua ♀	1.20–1.90	1.08–1.78	0.36–0.88	1.24–1.37	0.44–0.49	1.25–1.51	0.17–0.22	1.27–1.31	0.46–0.73	1.81–2.13	1.21–1.75	0.14–0.22	0.94–1.05	2.19–2.28	1.45–1.62
gracilenta ♀	1.53	1.77	0.76	0.95	0.50	1.18	0.23	1.59	0.34	1.79	1.31	0.17	0.98	1.93	1.28
grossa ♀	1.42–2.53	2.24–2.97	1.06–1.58	0.95–1.47	0.66–1.13	1.80–2.67	0.28–0.44	1.90–3.06	0.32–0.59	2.31–3.17	1.78–2.66	0.20–0.31	1.07–2.18	2.59–3.67	1.65–2.55
hypogaea ♂	1.58–2.20	1.54–2.40	0.81–1.26	0.81–1.23	0.37–0.61	1.17–1.69	0.22–0.33	1.58–2.57	0.20–0.44	1.63–2.34	1.26–1.84	0.18–0.27	1.24–1.71	1.58–2.84	1.01–2.22
hypogaea ♀	1.04–2.47	1.93–3.24	0.76–1.70	0.71–1.69	0.53–1.35	1.37–2.75	0.21–0.45	1.48–3.15	0.19–0.83	1.75–3.71	1.54–3.18	0.12–0.30	0.96–2.00	2.01–4.00	1.41–2.70
luctuosa ♂	1.93	2.03	1.11	1.08	0.47	1.51	0.32	2.36	0.40	2.07	1.60	0.26	1.41	2.31	1.60
luctuosa ♀	2.09–2.44	2.39–2.90	1.16–1.57	0.97–1.48	0.80–1.02	2.12–2.78	0.36–0.50	2.49–2.83	0.52–0.53	2.49–3.20	1.99–2.84	0.18–0.31	1.57–1.94	3.13–4.02	2.11–2.31
luteola ♀	2.00	2.13	1.03	1.18	0.83	2.38	0.30	2.30	0.48	2.88	2.35	0.20	1.30
macrocephala Ƌ	1.43–2.10	1.51–2.18	0.82–1.03	0.49–1.30	0.43–0.57	1.41–1.65	0.23–0.33	1.85–2.49	0.33–0.46	1.89–2.30	1.65–1.76	0.17–0.21	1.24–1.80	1.73–2.64	1.32–1.65
macrocephala ♀	1.76–2.39	2.22–3.08	0.98–1.49	1.09–1.52	0.60–1.10	1.95–2.51	0.31–0.44	1.96–2.98	0.37–0.55	2.78–3.40	2.16–2.77	0.23–0.27	1.44–1.74	2.85–3.31	1.90–2.53
pennata ♀	2.47	2.82	1.29	1.44	1.00	2.62	0.41	2.76	0.59	3.29	2.59	0.26	1.59	3.41	2.26
pinguis ♂	1.53–2.05	1.36–2.07	0.81–1.14	0.93–1.14	0.41–0.80	1.09–1.76	0.26–0.37	1.87–2.47	0.28–0.44	1.93–2.42	1.51–1.77	0.15–0.31	1.23–1.54	2.15–2.56	1.48–1.87
pinguis ♀	1.28–2.18	1.81–2.83	0.73–1.48	0.86–1.66	0.58–1.01	1.49–2.26	0.24–0.42	1.90–2.67	0.24–0.81	2.17–2.83	1.69–2.42	0.14–0.41	1.10–1.69	2.20–3.05	1.60–2.19
proserpina ♀	1.64–2.41	2.18–2.50	1.36–1.59	1.17–1.18	0.72–0.91	2.00–2.14	0.33–0.39	2.34–2.45	0.43–0.45	2.55–2.76	1.95–2.00	0.27–0.30	1.36–1.59	2.59–2.80	1.75–2.00
rhenana ♀	2.55	3.72	1.94	1.78	1.01	2.75	0.38	3.36	0.73	3.48	2.55	0.34	2.71	3.44	2.18
sluiteri Ƌ	1.47–1.81	1.47–1.60	0.41–0.48	0.84–1.14	0.53	1.20–1.31	0.15–0.22	1.41–1.68	0.34–0.47	1.34–1.54	1.05–1.30	0.08–0.16	1.00–1.20	1.66–2.13	1.09–1.36
sluiteri ♀	1.28–2.13	1.80–2.54	0.46–1.03	1.09–2.06	0.43–0.80	1.33–1.90	0.16–0.28	1.29–2.13	0.29–1.05	1.93–2.70	1.56–2.31	0.14–0.23	0.85–1.57	2.29–2.98	1.27–2.35
sturmi ♀	2.21	2.62	1.21	1.25	0.83	2.02	0.33	2.58	0.58	2.75	2.29	0.25	1.83	2.79	1.81
stygia ♀	0.88–2.20	1.64–2.68	0.68–1.59	0.78–1.86	0.37–0.99	1.26–2.24	0.22–0.44	0.99–2.92	0.23–0.85	1.61–2.86	1.40–2.30	0.09–0.30	0.79–1.72	1.93–3.10	1.26–2.07
winnertzi ♀	1.99–2.69	2.18–2.93	1.01–1.51	0.98–1.25	0.74–1.07	1.79–2.55	0.32–0.45	2.21–4.60	0.39–0.64	2.48–3.48	1.98–2.61	0.21–0.22	1.38–2.13	3.26–3.59	2.07–2.27

Additional material (all in GDKE): Males: GDKE PE 1995 8363 (part and counterpart), GDKE PE 1995 8504 (part and counterpart, pyritised). Females: GDKE PE 1995 6310, PE 1997 5109, PE 1997 5738, PE 2008 5005, PE 2009 5980, LACMIP 2533.1087ab, 2533.1088ab. Isolated wings: GDKE PE 1995 6611, PE 1995 8265, LACMIP 2533.1279. Description : Female (N=14, figs. 21, 23–26, 108–109): Entirely black, total length 13.3–15.5 mm (N=7) Head: Length 1.4 – 1.9 mm (N=7), width 1.3 mm (N=3), relatively small. Ocellar tubercle not prominent. Antenna nearly as long as head, flagellum probably 9-segmented. Flagellum length 0.99–1.22 mm (N=4), width 0.19–0.25 mm (N=4). Thorax: Length 3.3–4.3 mm (N=12), width 2.7–3.5 mm (N=5). Entirely black. Pile not apparent in specimens at hand. Haltere black. Legs: Fore femur 2.6–3.3 mm long (N=3), 0.56–0.68 mm wide (N=3), fore tibia 3.1–3.6 mm long (N=2), 0.35 mm wide (N=1), hind femur 4.6–5.0 mm long (N=4), 0.67–0.83 mm wide (N=4), hind tibia 4.9–5.1 mm long (N=3), 0.42–0.48 mm wide (N=3), hind first tarsomere 1.4–1.6 mm long (N=2), 0.37 mm wide (N=1). Wing (fig. 109): Length 10.9–14.3 mm (N=14), width 4.3–5.6 mm (N=13), length/width = 2.32–2.70 (N=13). Dark blackish fumose, costal cell darkened. Pterostigma indistinctive. R 2+3 medium-length, oblique, evently curved. Costa extends to apex of R 4+5 , which is gently curved. Posterior veins weak, difficult to make out, CuA 2 apically rather strongly curved basad. Vein measurements are given in Table 4 . Abdomen: Length 8.0– 11.3 mm (N=9), width 3.2–4.2 mm (N=7). rather stout, cylindrical. Male (N=3, figs. 22, 110–113): Entirely brownish black. Total length 9.0–13.0 mm (N=2). Head: (fig. 111) Length 1.5 mm (N=1), width 1.6 mm (N=1). Thorax: Length 3.3–3.8 mm (N=3), width 3.0 mm (N=2). Legs: Long and slender. Femora basally yellowish-brown, apically dark. Fore and mid tibiae and tarsi black, slender. Hind leg with tibia light brown, black-tipped, slender, spur fine and sharp. Fore femur 2.3 mm long, 0.52 mm wide (N=1), fore tibia 2.2–2.4 mm long (N=2), 0.25–0.28 mm wide (N=2), fore first tarsomere 0.94 mm long (N=1). Hind femur 3.8–4.1 mm long, 0.58–0.61 mm wide (N=2), thin in basal two thirds, apically clavate. Hind tibia 2.8–4.6 mm long (N=3), 0.61 mm wide (N=1). Hind first tarsomere 1.3 mm long, 0.42 mm wide (N=1), slightly swollen, spindle-shaped. Wing (fig. 110): Length 9.4–10.3 mm , width 3.5–4.1 mm , length/width = 2.5–2.7 (N=2). Uniformly dark brownish fumose, veins dark brown, fine and fairly distinctive. Pterostigma indistinctive. R 2+3 oblique, relatively straight. R-M vertical, M with relatively long stem and short, rounded, symmetrical fork. CuA-veins apically straight. Vein measurements are given in Table 4 . Abdomen: Length 6.6–7.4 mm (N=3), width 1.8–2.0 mm (N=2). Rather slender, slightly conical. Terminalia (figs. 112–113): Width of hypopygium 1.3 mm (N=2) Outline of hypopygium rectangular. Epandrium dome-shaped, apically rounded, strongly pilose. Gonostylus 0.51–0.68 mm long (N=3), straight, robust, moderately pilose, apically rounded. Last sternite dome-shaped with blunt, T-shaped mesal process. Discussion : The senior name of this species was listed in the genus Bibio by Evenhuis (2014) . The type of Helophilus primarius was originally interpreted as having paired spots on the abdomen, hence it was classified as a syrphid, though it obviously does not belong there ( Kotthoff & Schmid 2005 ). We cannot find any evidence of such spots, the wing venation is very similar to Phthiria dubia , which was originally placed in Bombyliidae . It seems a bit unclear if Helophilus primarius was formally published by Germar (1837) , in the copy of his work which we have seen there is a plate of the specimen ( Germar 1837 , Fasc. XIX Plate 25) but no printed description, just a handwritten diagnosis which may have been added at a later stage. In the material from Enspel there are several poorly preserved Plecia females which are substantially smaller than the well-preserved Plecia dubia specimens, suggesting the presence of a second species in the fauna. None of these specimens are well enough preserved to be identified at the species level, however. Statz (1943: 6) synonymised Plecia superba Meunier, 1915 with Plecia abava without having studied any specimens of P. abava . The wings of Plecia superba clearly differ from the type of Plecia abava and this synonymy is not valid in our opinion.