Formosibittacus, Li & Ren & Shih, 2008

Li, Yan-Li, Ren, Dong & Shih, Chung-Kun, 2008, Two Middle Jurassic hanging-flies (Insecta: Mecoptera: Bittacidae) from Northeast China, Zootaxa 1929 (1), pp. 38-46 : 39

Genus Formosibittacus gen. nov.

Type species. Formosibittacus macularis sp. nov.

Etymology. The generic name is derived from the Latin word formos- (beautiful) and Bittacus (a recent genus of Bittacidae ).

Diagnosis. Antennae less than half as long as body; Sc long, beyond the fork of R 4+5; one subcostal crossvein (Scv) between Sc and R 1; vein R 1 running through pterostigma, it weakly and smoothly arching before apex, lacking sharp bend; one pterostigmal cross-vein (Pcv); vein R 1 joining to R 2+3 by three cross-veins before pterostigma; vein Rs four branches, dividing before the fork of M; vein M four branches, the fork of M 3+4 before posterior part of ‘Kreuz der Bittaciden’ (r 4+5 -m 1 and m 1+2 -m 3 cross-veins); two cross-veins between M 4 and CuA; and vein 1A reaching margin of wing about level of first fork of Rs.

The new scorpion-fly can be recognized as Bittacidae on the basis of characteristics of legs and forewings: right fore leg long and slender, with a single, predatory tarsal claw, the fifth tarsal segment folding back onto the fourth; wings narrow basally, broadened distally; pterostigma well developed; CuA coalesced with M basally for a short distance.

Based on the forewing venation, the new genus is similar to living genus Hylobittacus Byers 1979 , but it differs from it mainly by the following features: vein R 1 weakly and smoothly arching before apex, lacking sharp bend, three cross-veins between R 1 and R 2+3 before pterostigma. On the basis of the forewing venation, the new genus shows close similarity with fossil genera Preanabittacus Novokshonov 1993 , Sibirobittacus Sukatcheva 1990 and Antiquanabittacus Petrulevičius & Jarzembowski 2004 . But it can be distinguished from them by the following characters: Sc long, extending beyond the fork of R 4+5; three cross-veins between R 1 and R 2+3 before pterostigma; and M 3+4 divided before ‘Kreuz der Bittaciden’ aligned.

At present, one living genus ( Bittacus Latreille 1805 ) and four fossil genera ( Liaobittacus , Megabittacus , Sibirobittacus , and Megolbittacus) have been recorded in China. The new genus differs from them in one Scv, one Pcv, and three cross-veins between R 1 and R 2+3. Furthermore the new genus can be distinguished from other currently known genera by a combination of the following characters: Rs divided into four branches; one Pcv; three cross-veins connecting R 1 and Rs; M divided into M 1+2 and M 3+4, M 3+4 dividing before posterior part of ‘Kreuz der Bittaciden’; two cross-veins between M 4 and CuA; and 1A terminating beyond the fork of Rs. Therefore, it is reasonable to erect the new genus Formosibittacus .