IXALIDIIDAE HEMP , SONG & RITCHIE, 2025

KEY TO GENERA OF IXALIDIIDAE HEMP, SONG & RITCHIE N. FAM. ( MALES)

1. Prosternal tubercle conical ( Fig. 6B), hind tibia with external apical spine ( Fig. 3C); fastigium of vertex almost as long as, or longer than its basal width ( Fig. 3D, F) .................................................................................. 2

— Prosternal tubercle transverse, lamelliform; hind tibia lacking external apical spine; fastigium of vertex much shorter than its maximum basal width ( Fig. 4 A-C) ...................................................................................... 3

2. Pronotum with two subconical dorso-medial projections and two pairs of subconical dorso-lateral projections, variably expressed, in prozona and metazona ( Fig. 3A) .............................................. Barombia Karsch, 1891 View in CoL

— Pronotum lacking subconical dorso-medial projections and subconical dorso-lateral projections in prozona and metazona, but with variably expressed dorso-medial tubercles ( Fig. 3B) ............................ Mazaea Stål, 1876 View in CoL

3. Small species ( 16-21 mm); abdominal apex slender, nymph-like, with tergites 9 and 10 slim, tapering; supra-anal plate bilaterally symmetrical; basal part rhomboid, deeply inset into tergite 10, with sharp lateral margins; transverse suture almost straight; apical portion acutely triangular, longer than its basal width ( Fig. 5 A-C); hind tibiae usually reddish at least in apical third ......................................................... Ixalidium Gerstäcker, 1869 View in CoL

— Larger species ( 18-27 mm); abdominal apex plump, with tergites 9 and 10 robust; supra-anal plate either not visible or with transverse suture medially incurved ( Fig. 5 D-H); hind tibiae of variable coloration (brown, grey, straw, violet), but never reddish ................................................................................................................... 4

4. Abdominal apex bilaterally asymmetrical, tergites 9 and 10 dorsally fused and twisted, usually with short or elongated pointed process arising from basal section, normally on right side only; basal part of supra-anal plate not clearly distinct, apical portion either internalised or, if visible, then vestigial; subgenital plate acutely pointed in dorsal view ( Fig. 5H) ............................................................................................ Tangana Ramme, 1929 View in CoL

— Abdominal apex bilaterally symmetrical; tergite 10 and anterior margin of supra-anal plate either forming raised median furcula ( Fig. 5D, E) or flat ( Fig. 5F, G); basal and apical portions of supra-anal plate clearly visible; transverse suture medially incurved, flanked by excurved and raised lateral flanges; subgenital plate broadly rounded with pointed tip ( Fig. 5 E-G) .................................................... Rowellacris Ritchie & Hemp n. gen.