Hylicella Evans, 1956

Lambkin, Kevin J., 2020, Revision of the Hylicellidae of the Late Triassic of Queensland (Hemiptera Cicadomorpha: Hylicelloidea), Zootaxa 4790 (3), pp. 525-539 : 527

Hylicella Evans, 1956

Hylicella Evans, 1956: 195 .

Type species. Hylicella colorata Evans, 1956 , by original designation.

Emended diagnosis. Tegmen almost 3 times longer than wide; pre-nodal area finely to somewhat coarsely punctate, delimited apically by the suggestion of a nodal line running transversely at the level of the forks of RA, M and CuA; costal margin broadly convex proximally, almost straight distally, apex somewhat broadly rounded; peripheral membrane of even width; costal space c. 3 times as wide as medial cell; R and M separating near apex of basal cell; basal cell quite broad proximally then tapering and closed distally by a fusion for a short length of M and CuA; R fork just before tegmen length, well before M fork which is aligned with RA fork and proximal to CuA fork; RA 1 obliquely angled towards anterior margin, simple; RA 2 continuing in line with RA stem towards apical anterior margin, the RA 1 + RA 2 field thus occupying a very small area at that margin; RA 2 with 2 short branches; RP simple; one ir, running from RA 2 or RA 2b; one r-m, proximal to ir, running to M 1+2, holotype with an additional more distal r-m running to M 1; M with 4 branches, one specimen ( QMF3686 ) with an additional fork on M 3; im between M 2 and M 3 or M 3+4, quite long, intra-medial cell thus short and broad, only c. 2 times longer than wide, relatively large, occupying a significant portion of post-nodal area; CuA 1 with base perpendicular to CuA→CuA 2, crossvein-like, fused with M 3+4 for a short length, its free apical piece curved postero-apically, about the same length as M 4; CuA 2 continuing in line with CuA, very short; apical crossvein field not aligned; clavus not preserved .

Notes. As this is the type genus, subsequent authors (e.g. Becker-Migdisova 1962 a, Carpenter 1992, Hamilton 1992, Jell 2004) have maintained its placement in the Hylicellidae , although it is of note that Evans himself later preferred a more general ascription of most of his 1956 genera to the Cicadelloidea only, rather than ‘to particular Families’ ( Evans 1961). Hylicella differs from all other hylicellids, except Conjucella Shcherbakov, 2012 , in the partial fusion of CuA 1 and M 3+4. Conjucella , however, is otherwise quite distinct, inter alia, in wing shape, structure of the basal cell, RP partially fused with M 1+2, a narrower intramedial cell, and much reduced apical venation ( Shcherbakov 2012, figs 1–3). Evans (1956) also mentioned the presence of two RP-M crossveins as diagnostic, but as noted in the emended diagnosis above, the second more distal one is absent in all specimens except the holo- type where it is apparently simply an individual variation. In establishing Hylicella, Evans (1956) also described a second species, H. reducta Evans, 1956 , for which Becker-Migdisova (1962b) established a new genus Hylicellites Becker-Migdisova, 1962 . A re-examination of the holotype of the species, however, has identified it as a poorly preserved tegmen of Mesojassus australis ( Evans, 1956) (Cicadelloidea: Archijassidae ), with which H. reducta has now been synonymised ( Lambkin 2020).