Fossils from the Middle Jurassic of China shed light on morphology of Choristopsychidae (Insecta, Mecoptera) Author Qiao, Xiao Author Shih, Chung Kun Author Petrulevicius, Julian F. Author Dong, Ren text ZooKeys 2013 318 91 111 http://dx.doi.org/10.3897/zookeys.318.5226 journal article http://dx.doi.org/10.3897/zookeys.318.5226 1313-2970-318-91 Family Choristopsychidae Martynov, 1937 Emended diagnosis. Forewing broad oval or subtriangular, field between C and ScP comparatively broad; ScP well developed and forked twice, forming three long branches; RA unforked, one crossvein between ScP and RA and between RA and RP; RP and MA both with two branches; MP with five branches, and the MP4+5 forking basal to the MP2+3 forking; MP and CuA merged at the base; CuA strongly bent at its mid point; an oblique crossvein between CuA and CuP; a curved crossvein between the midpoint of CuA and MP5; CuP, 1A and 2A almost parallel. Hind wing, similar in shape to the forewing but slightly smaller, ScP short, forked twice, the second bifurcation coalesces with RA for a short distance; RP and MA both with two branches; MP with five branches, the stem of MP4+5 forked earlier than that of forewing, and with a crossvein to CuA; CuA almost straight. Head, oviform with big and oval compound eyes; antennae long and filiform; small chewing mouthpart. Thorax: prothorax smaller than mesothorax and metathorax. Legs: long and slender, all legs nearly of the same shape, but hind legs longer than fore legs and mid legs, and femora wider than tibia, and tibia longer than femora. Abdomen slender, tapering apically, about eleven segments and the female terminal segment with cercus.