Pseudocestius, Dietrich & Nguyen & Pham, 2020

Dietrich, Christopher H., Nguyen, Huong T. T. & Pham, Hong Thai, 2020, New genera, new species and new records of leafhoppers (Hemiptera: Cicadellidae) from Vietnam, Zootaxa 4877 (2), pp. 241-273 : 252-253

Pseudocestius n. gen.

Type species. Pseudocestius cucphuongensis n. sp.

Description. Medium-sized, robust leafhoppers. Coloration stramineous, with numerous tiny brown spots and symmetrical larger black and brown maculae. Head short and broad; crown flat, broadly rounded anteriorly, with anterior and posterior margins parallel, length less than half basal width between eyes, basal width between eyes less than twice eye width, disc glabrous, anterior margin shagreen, rounded to face; ocelli large, on anterior margin of crown and only partly visible from above, separated from eye by slightly more than one ocellar diameter; eye mesal margin with broad, shallow emargination adjacent to antennal base; antennal base slightly below midheight of eye, antenna shorter than head width; face in profile less than 45º from horizontal, wider than tall in anterior view; frontoclypeus broad, moderately tumid, shagreen; lateral frontal sutures obsolete above antennal pits; anteclypeus flat, parallel-sided, extended to ventral margin of face, apex truncate; lorum flat, approximately as wide as anteclypeus, well separated from lower margin of maxillary plate; maxillary sensillum well separated from lateral margin of lorum; gena with obtuse emargination below eye; rostrum not extended beyond front trochanter. Pronotum slightly convex, slightly declivous anteriorly, surface with very weak transverse striations and indistinct punctations, lateral margin carinate but very short, eye nearly touching forewing base. Exposed part of mesonotum and scutellum wider than long, scutellum transversely rugose and slightly protuberant dorsad.

Front femur AM1 near ventral margin; AV1 longer than IC setae but similar in width; IC with single row of ca. 8 long, fine setae; AV with 6–8 short, stout setae in single row basally; tibia with dorsal surface rounded, rows AD and PD with 1 and 4 setae, respectively, AV with numerous macrosetae, PV without macrosetae. Middle trochanter with stout ventroapical seta; femur AV with numerous short, stout setae basally and single slightly longer seta distally. Hind femur macrosetae 2+2+1, tibial rows PD, AD, AV with 16, 10 and 13 macrosetae, PD setae alternating short and long, AD with 1–4 short setae between successive macrosetae; tarsomere I with 2 rows of simple plantar setae, pecten with 3 platellae, inner seta of pecten tapered and slightly shorter than platellae. Forewing venation complete, unmodified except central anteapical cell divided by crossvein and clavus with extra partial crossveins, three anteapical cells and four apical cells present; appendix moderately developed, restricted to anal margin. Hind wing venation complete, unmodified.

Male 2S apodemes long, thin, divergent and capitate, extended to posterior margin of sternite III. Pygofer incised nearly to base dorsally, lobe with group of macrosetae posterodorsally and group of long, fine setae ventrolaterally near base, inner surface with numerous conspicuous sensilla preapically, apex of lobe produced into spinelike process. Segment X short, weakly sclerotized, without processes. Valve triangular, wider than long. Subgenital plates separate from each other and movably articulated to valve, large, boatlike, tapered from base to apex, lateral margin slightly concave, apex truncate, with lateral band of numerous macrosetae and lateral row of fine setae slightly shorter than macrosetae. Style broadly bilobed basally, preapical lobe short and rounded, apophysis long and nearly straight, apex cheliform with preapical point and curved distal hook. Connective H-shaped, anterior arms bowed laterad but approaching each other anteriorly, stem deeply emarginate with lateral arms articulated to atrial processes of aedeagus. Aedeagus with atrium broadened dorsally and extended laterally into pair of looplike structures, each with elongate process articulated to atrium mesally and to ridge on inner wall of pygofer laterally; aedeagal shaft simple, tubular, curved posterodorsad; gonopore apical. Partially sclerotized dorsal connective present between aedeagal atrium and base of anal tube.

Etymology. The genus name, a masculine noun, combines “Pseudo” (false) with Cestius , the name of a superficially similar genus of Opsiini .

Notes. Pseudocestius resembles some genera of Opsiini , particularly Opsius Fieber and Cestius Distant (treated as separate valid genera by Dai et al. (2010) but considered synonyms by some authors) in having the crown short and broad with a rounded anterior margin. It also resembles many genera of Opsiina in having a dorsal color pattern consisting of numerous minute brown spots. It differs from Opsiini in having the aedeagus with a single shaft and gonopore. Although, as in Hochiminhus n. gen., Pseudocestius lacks distinct punctations on the dorsal integument and has the crown rounded to the face, this genus is tentatively assigned to Punctulini based on the following traits: head not produced, male 2S apodemes elongated, divergent and capitate, subgenital plates with setae scattered, aedeagal shaft simple, without processes, dorsal connective present; style lacking preapical lobe, apex cheliform.