Ipsvicia Tillyard, 1919

Lambkin, Kevin J., 2020, Revision of the Ipsviciidae of the Late Triassic of Queensland (Hemiptera Cicadomorpha: Scytinopteroidea), Zootaxa 4860 (4), pp. 503-520 : 506-507

Ipsvicia Tillyard, 1919

Ipsvicia Tillyard, 1919a: 878 .

Type species. Ipsvicia jonesi Tillyard, 1919 , by original designation.

Emended diagnosis. Tegmen c. 3 times longer than wide; surface sculpture complex, comprising numerous variably shaped patches of fine tubercles each encircled by a smooth, very narrow margin, the patches set in a coarser tuberculate/punctate groundmass, a little finer apically; costal margin distinctly convex; basal cell short and broad, not extending to midpoint of PCu; R evenly convex, parallel with costal margin, the basal R cell therefore of about equal width for entire length; two r-m; CuA strongly angulate at m-cua; base of 1A slightly upcurved.

Description. Tegmen c. 14–22 mm long; marginal membrane only slightly widened postero-apically; costal fracture fairly upright; bSc variable convex; dSc very weakly developed, running along middle of costal space; R with 4–6 mostly simple post 1r-m branches; M+CuA stem a little variable in length, extending just beyond ½ length of PCu; apical section of CuA directed posteriorly, straight or slightly convex; clavus extending to c. 0.6 tegmen length; 1A about as long as PCu+1A. Hind wing: size variable in proportion to variable size of the individual, maximum length c. 13.8 mm, maximum width c. 5.9 mm in measurable specimen; R, M, CuA and CuP very closely approximated basally, CuA and CuP apparently without a common stem; R, M and CuA then more or less parallel, directed towards apical margin, gradually diverging apically, apex of CuA upcurved and forming an apical loop with R and M enclosing a small network of terminal short branches and crossveins; a long, backwardly oblique m-cua (the single cua-cup illustrated by Tillyard (1923) and Evans (1963) not detected); CuP simple, very long, sinuous, its apex broadly separated from that of CuA and PCu; both PCu and 1A with thickened bases, both straight basally and sinuous apically, CuP and PCu approximating each other at their mid-points; anal area noticeably crinkled; marginal membrane well developed.

Notes. The hind wing venation is noteworthy for the close alignment and apical looping of R, M and CuA, and the long, simple and sinuous CuP, PCu and 1A. The other known hind wings of the Scytinopteroidea are those of several species of Scytinoptera Handlirsch, 1904 , illustrated by Becker-Migdisova (1948, figs. 2, 33, 39–43). They apparently lack a marginal membrane, and their venation is much simpler than that of Ipsvicia , with M and CuA directed postero-apically rather than apically, R, M and CuA without apical looping, CuA and CuP with a common stem, CuP, PCu and 1A almost straight rather than sinuous, and without the long, backwardly oblique m-cua. Indeed, as noted by Evans (1956), the venation of Ipsvicia was unlike any of the Palaeozoic or Mesozoic homopteran hind wings known at that time (see also those illustrated by Becker-Migdisova 1961), and it differs from that of the extant families of Cicadomorpha (see figures in Kramer 1950). It might be observed, however, that the form of R, M and CuA bears some resemblance to that of Heteroptera: Nepomorpha ( Popov 1971, plate 52).