Bibio vulpinus Statz, 1943

Skartveit, John & Wedmann, Sonja, 2021, A Revision of fossil Bibionidae (Insecta: Diptera) from the Oligocene of Germany, Zootaxa 4909 (1), pp. 1-77 : 51-52

Bibio vulpinus Statz, 1943 (figs. 80–81, 203–204)

Bibio vulpina Statz, 1943: 49 .

Bibio Ƌ Nr. 3 Statz, 1943: 53.

Bibio Ƌ Nr. 5 Statz, 1943: 55.

Bibio vulpinus Statz: Evenhuis 1994: 126 .

Localities: Rott

Material examined: Holotype (female) of Bibio vulpina LACMIP 2533.245ab / LACMIP Type 3375 (fig. 80).

Additional material, males: LACMIP 2533.228/ LACMIP Type 3358 (fig. 81, depicted specimen of Bibio Ƌ Nr. 3), 2533.230/ LACMIP Type 3360 (depicted specimen of Bibio Ƌ Nr. 5), 2533.2227, 2533.2234.

Description:

Female (N=1, figs. 80, 203–204):

Total length 13.3 mm

Head (fig. 204): Length 1.2 mm, width 0.9 mm. Rather small, dark brown. Antenna cylindrical and rather slender, flagellum 0.7 mm long, 0.16 mm wide, 7-segmented?, palpus rather long, terminal segment slender and cylindrical. Complex eye rather large, occupying most of side of head, not protruding.

Thorax: (fig. 204) Lenght 3.2 mm, width 2.6 mm. Blackish-brown.

Legs: Light brown, tarsi apically darkened, rather robust. Fore leg not preserved. Hind femur 2.9 mm long, 0.6 mm wide, clavate, robust, hind tibia 3.0 mm long, 0.4 mm wide, relatively slender with long, straight, dark-tipped spur. Hind first tarsomere 1.1 mm long, 0.25 mm wide.

Wing: Length 7.9 mm. Hyaline, veins fine, dark brown and distinctive thoughout. Pterostigma oval, dark brown and distinctive. Subcosta long, fine and straight. Costa extends to apex of R 4+5. Basal Rs about three times as long as R-M. R 4+5 curved. Fork of M rather narrow, M-veins apically straight, crossvein dM-Cu meets M at furcation. CuAveins not preserved. Vein measurements are given in Table 5.

Abdomen: Length 9.3 mm, width 2.7 mm. Dark brown, a little spindle-shaped. Last tergite apically gently concave. Cerci rounded.

Male (N=4, fig. 81):

Total length 7.8–10.5 mm (N=3).

Head: Length 1.3–1.9 mm (N=3), width 1.6 mm (N=1). Ocellar tubercle small, antenna robust, flagellar segments not possible to count but not many

Thorax: Length 2.8–3.1 mm (N=3), width 2.4 mm (N=1), brownish-black, haltere brownish yellow.

Legs: stout and robust, light brown. Fore femur length 1.8 mm, width 0.6 mm (N=1). Fore tibia length 1.7–2.1 mm (N=2), relatively slender. Hind femur 2.8–2.9 mm long (N=2), 0.5–0.7 mm wide (N=2), robust, clavate, hind tibia 2.3–3.0 mm long (N=3), 0.5–0.6 mm wide (N=2), robust, spur very short. Hind first tarsomere 0.7 mm long, 0.4 mm wide (N=1), thick, spindle-shaped, more distal tarsomeres short and stout.

Wing: Length 5.7–6.6 mm (N=2), width 2.5 mm (N=1), length/width = 2.7 (N=1). Hyaline, R-veins brown, posterior veins colourless. Pterostigma small, brown, moderately distinctive. Costa extends to apex of R 4+5. Subcosta straight , indistinctive. Humeral vein not apparent. Basal Rs two to three times as long as R-M. R 4+5 strongly curved. Posterior veins scarcely possible to see .

Abdomen: Length 5.2–5.9 mm (N=2), width 2.0 mm, black, slightly conical.

Terminalia: Gonocoxites yellowish-brown. Epandrium apparently with pointed lobes, indentation between them relatively narrow and U-shaped. Gonostylus sickle-shaped as usual for genus, relatively small and slender. Hypopygium width 1.1–1.2 mm (N=2), gonostylus length 0.5 mm (N=1).