Mesoscytina magna sp. nov.

(Figs 9–10)

Material. Holotype tegmen QM F58700, Dinmore, collected by Robert Knezour.

Description. Tegmen 10.6 mm long, 4.0 mm wide, length/width 2.6; base of R and costal space as in M.

fistulae; RA only slightly inclined; basal section of RP (before rp–m) much shorter than in the other species of the genus; colour pattern similar to M. fistulae, but dark areas more extensive, the medial pale area narrower and the distal pale area apparently reduced to three spots (Fig.9).

Notes. Mesoscytina magna, from the Dinmore site of the Blackstone Formation, is distinguished from its congeners by its larger size, more upright RA, and shorter basal section of RP. The apparent forking of the posterior rather than the anterior branch of M (as in other species of the genus) is not considered significant as the basal connections of the apical venation, as evidenced by M. fistulae, are quite variable. The species name alludes to its larger size.