FAMILY URANORHAGIONIDAE ZHANG, YANG & REN FAM. NOV.

Type genus: Uranorhagio gen. nov.

Diagnosis: Body stout. Head round. Mesonotum slightly convex. Hind tibia with spur(s), empodia pulvilliform. Wing slender relative to body. Veins thick and strong. Vein Sc ending slightly beyond the middle of the wing; veins R 1 and Rs 1 long, vein R 2+3 distinctly and strongly bent upwards at base, vein R 5 ending at (or beyond) wing apex; veins M 1 and M 2 bifurcating, distal of crossvein m–m; cell sc wide open; cell r 4 slender; five posterior cells present and wide open, cell cup distinctly open; anal lobe small and narrow, alula unconspicuous.

Stratigraphic and geographic range: The Middle Jurassic, China.

Remarks: Uranorhagionidae fam. nov. is considered to be a member of the lower Orthorrhapha, because of the stout body, the presence of tibia spur(s), and pulvilliform empodia. Contrasting with other families of lower Orthorrhapha, this new family is somewhat similar to the Rhagionidae family. However, we cannot put these specimens in any known families, because of their special and unique wing venation. Therefore, we erect a new family in superfamily Tabanoidea for them. We can differentiate Uranorhagionidae fam. nov. from Rhagionidae by the following characters: veins Sc and R 1 long; vein R 2+3 fornical at base; vein CuA 2 short; cell d extending to near the wing margin (in Uranorhagio gen. nov.); hind femur swollen at apex; and nine abdominal segments. Also, this family is superficially similar to the Rhagionemestriidae family (especially for Iberomosca). But, we can easily separate the new family from Iberomosca by the following features: vein Rs 1 extends much longer than vein Rs 2; vein R 2+3 is fornical at the base; cell br is longer than cell bm; the cell cup is open at the wing margin; and there is no distinct diagonal vein.