Cavichiassus, Domahovski, 2021

Domahovski, Alexandre Cruz, 2021, Cavichiassus, a new genus of Hyalojassini (Hemiptera: Cicadellidae) from Brazil and first description of the genitalia of Neotrocnada rutasaca (Blocker) comb nov., Zootaxa 4926 (2), pp. 189-200 : 190-191

Cavichiassus gen. nov.

( Figs 1 ‾20)

Type species: Cavichiassus punctatus sp. nov.

Diagnosis. Forewing (Fig. 5) with appendix and first apical cell narrow, more membranous than adjacent cells; vein separating appendix and first apical cell complete. Protibia (Figs 2, 4) with dorsal surface flat, AD and PD margins carinated, but weakly expanded laterally. Genital capsule (Fig. 7), in repose, retracted into pregenital segment, less than half length of pygofer exposed. Ventral process of pygofer (Figs 7‾9) arising near base of subgenital plate and extending ventrad. Subgenital plate (Fig. 10) small, simple, without pseudostyles or setae, not enfolding lateral portion of pygofer. Connective amorphous. Style (Figs 11), very long, with apodeme and apophysis elongated. Aedeagus (Figs 12, 13) dorsal apodeme with pair of processes directed posterad.

Description. Medium-sized, robust leafhoppers. Head ( Figs 1 ‾3) short and broad, narrower than pronotum; crown not developed, nearly vertical, with texture rugose. Ocelli (Fig. 3) small, well separated from eyes and frons, equidistant from eyes and midline and from dorsal margin of crown and antennal ledge. Head (Fig. 2), in lateral view, with crown-face transition broadly rounded; frons strongly inflated. Head (Fig. 4), in ventral view, with face more than two times wider than long; frons small, surface with transverse striae and without setae, lateral margins rounded, convergent ventrally; frontogenal suture extending to antennal ledges; antennal ledge carinate, slightly rounded and oblique, concealing two basal antennal segments in anterior view; antenna short, length less than half width of vertex; gena broad, with long setae; ventrolateral margin slightly excavated ventrad of eye, completely concealing proepisternum; epistomal suture complete and distinct; lorum broad, with many long setae, maximum width approximately equal to that of clypeus, lateral suture rounded and incomplete dorsally, extended nearly to mid-length of lateral margin of frons; clypeus convex with long setae, approximately 1.4 times longer than wide, lateral margins parallel, apex carinated and straight.

Pronotum ( Fig. 1 ), in dorsal view, with anterior margin slightly rounded, posterior margin slightly excavated; surface without setae, with conspicuous transverse striae, except near anterior margin; lateral margins convergent anterad, carinate, as long as eye; in lateral view (Fig. 2) convex and strongly declivous anterad; proepimeron transversely rugose. Exposed part of mesonotum and scutellum ( Fig. 1 ) shorter than median length of pronotum, surface with transverse striae.

Forewing ( Figs 1 , 2, 5) tectiform at rest; with small punctations with minute setae; venation distinct; two discal and three closed anteapical cells present; appendix and first apical cell narrow, more membranous than adjacent cells; vein separating appendix and first apical cell complete (not evanescent apically); apical cells short; vein R with 5‾6 branches. Hind wing veins R4+5 and M1+2 confluent distally.

Profemur (Fig. 3) moderately elongated, 2.5 times longer than high; PD, AD and AM rows formed by scattered short setae, PD1 and AD1 setae developed but thin and AM1 undifferentiated; IC row formed by scattered setae, continuous with AV row; AV and PV rows formed by thin setae. Protibia (Figs 2, 4), in cross-section, not circular, dorsal surface flat, AD and PD margins strongly carinated, but weakly expanded laterally; AD and PD rows with undifferentiated setae and 4‾5 longer setae; AV and PV rows formed by short setae, slightly thicker toward apex. Hind femur setal formula 2+1. Metatibia PD, AD and AV rows with 16‾17, 10 and 12‾14 macrosetae respectively; AD row without intercalary setae between macrosetae; PV row formed by few short and acute apically setae; first tarsomere without enlarged dorsoapical seta; ventral surface with few undifferentiated setae; pecten with 6 platellae flanked by short tapered lateral setae; second tarsomere pecten with 3 platellae.

Male terminalia. Genital capsule (Fig. 7), in repose, retracted into pregenital segment, less than half of apical portion of pygofer exposed. Pygofer (Figs 7, 8), with ventral processes conspicuous (Figs 7‾9). Subgenital plate (Figs 7, 8, 10) small, simple, without pseudostyles or setae, not enfolding lateral portion of pygofer. Connective amorphous. Style (Fig. 11), very long, with apodeme and apophysis elongated. Aedeagus (Figs 12, 13) dorsal apodeme with pair of processes directed posterad.

Female terminalia. Ovipositor slender, evenly curved dorsad, not surpassing pygofer apex. First valvula (Figs 16, 17) with dorsal sculptured area areolate. Second valvula (Figs 18, 19) with five distinct teeth widely spaced. Gonoplac (Fig. 20) ventral margin with few short macrosetae.

Distribution. Brazil (Paraná).

Etymology. The genus name (masculine noun), was formed by the prefix “Cavichi”, an homage to Dr. Rodney Ramiro Cavichioli, for his contribution to the knowledge of Neotropical Cicadellidae and the suffix “assus”, used in names of Hyalojassini .

Notes. The new genus will key out at couplet 7 in Blocker’s (1979) key to the New World Iassinae , and differs from Jivena Blocker, 1976 having male sternite VIII shorter (very long, with posterior margin produced posterad and rounded in Jivena ); the ventral margin of the pygofer without long setae (many long setae in Jivena ); the style curved (straight in Jivena ); and the subgenital plate flattened, without setae (digitiform and with many apical setae in Jivena ). All genera that follow couplet 8 ( Aztrania Blocker, 1979 , Gehundra Blocker, 1976 and Grunchia Kramer, 1963 ) differ in having the subgenital plate with a pseudostyle, that is absent in the new genus.

Among the Neotropical genera of Iassinae , Cavichiassus gen. nov. shares some similarities with Neotrocnada as follow: (1) forewing tectiform at rest; (2) forewing with many small punctations with minute setae; (3) forewing vein R with several branches; (4) proepimeron transversely rugose; (5) protibia with dorsal surface flat and AD and PD margins carinated; (6) hind femur setal formula 2+1; (7) ventral process of pygofer conspicuous, arising near base of style and extending ventrad. However, the new genus can be easily separated from Neotrocnada by the anterior margin of the head without an abrupt transverse fold at the level of the antennal ledge; the frons inflated; and the forewing with appendix and first apical cell narrow, both more membranous than adjacent cells.

Figures

FIGURES 1─13. Cavichiassus punctatus gen. et sp. nov., male holotype. 1, Habitus, dorsal view. 2, Habitus, lateral view. 3, Head, frontal view. 4, Head, ventral view. 5, Forewing. 6, Sternite VIII, ventral view. 7, Genital capsule, lateral view. 8, Pygofer, valve, and subgenital plate, lateral view. 9, Ventral process of pygofer, lateral view. 10, Subgenital plate, ventral view. 11, Style and enlarged view of apex, lateral view. 12, Aedeagus, lateral view. 13, Aedeagus, posterior view. Scale bars in mm.