Eoscartoides Evans, 1956

Lambkin, Kevin J., 2016, Revision of the Dysmorphoptilidae (Hemiptera: Cicadomorpha: Prosboloidea) of the Queensland Triassic — Part 2, Zootaxa 4092 (2), pp. 207-218 : 208-209

Eoscartoides Evans, 1956

Eoscartoides Evans, 1956: 220 .

Type species. Eoscartoides bryani Evans, 1956 , by original designation.

Mesonirvana Evans, 1956: 191–192. Syn. nov.

Type species. Mesonirvana abrupta Evans, 1956: 192, fig. 5E, by original designation.

Mesocixiodes Tillyard, 1922: 462 (partim).

Type species. Mesocixiodes termioneura Tillyard, 1922: 462, text fig. 82, plate 53, fig. 34, by original designation.

Diagnostic characters. Tegmen over 11 mm long, lobate; precostal carina and marginal membrane distinct; hypocostal carina short; punctation very fine, somewhat coarser basally and posterior to Pcu; hyposubcostal carina long, only very slightly concave; strigil in basal costal space large and well developed, quite coarsely rugose, extending in an arc from just above R to costal margin; no swellings detected on hind margin of clavus, its proximal corner strongly bent downwards; stem of RA very short, its primary fork just beyond clavus ½ length, proximal to level of CuA fork; stem of RA1 directed anteriorly in line with stem of RA, entering costal margin well before tegmen apex, with at least 2 anterior branches; RA2 extensive, occupying a large area antero-apically, with at least 3 anterior branches; RA2 and RP joined by a crossvein; M1+2 deeply forked; M3+4 simple, or with a terminal fork only; M and CuA joined basally by a short crossvein (the “arculus”); apical m-cu inclined; CuA1 gently concave; CuA2 straight.

Notes. The type species of Eoscartoides and Mesonirvana are synonyms. As both generic names were established in the same paper, as first reviser (ICZN Article 24), I have chosen Eoscartoides as the senior synonym on the grounds that its type specimen is better preserved and that all subsequent published specimens (Evans 1961) have been identified as Eoscartoides bryani . The type specimen of the type species, Mesonirvana abrupta Evans, preserves only the apical region of the tegmen and is somewhat distorted, whereas that of E. bryani is almost complete, and in particular shows the characteristic strigil in the basal costal space (see photographs at pages 44 and 56 of Jell 2004).

The large and distinctly shaped strigil, the very short stem of RA, and the basic pattern of forking of M (M1+2 deep, M3+4 simple) are considered as the apomorphies for Eoscartoides . The structure and shape of the strigil is apparently the same as that of the unnamed Triassic sspecies from the Madygen Formation of Kyrgyzstan illustrated by Shcherbakov and Popov (2002, fig.184) which also appears to have similar venation to Eoscartoides . Even though only one specimen of each of the three species of Eoscartoides preserves a substantial part of the clavus (QM F3697a/b, GSQ 318a, QM F58592 ), the peculiar bend at the proximal corner is present in all three and is probably the basal part of the commissural carina (Dmitry Shcherbakov, pers com.) (Figs 3,4,9).