Lamelliassus, Dai, Wu, Dietrich, Christopher H. & Zhang, Yalin, 2015

Dai, Wu, Dietrich, Christopher H. & Zhang, Yalin, 2015, A review of the leafhopper tribe Hyalojassini (Hemiptera: Cicadellidae: Iassinae) with description of new taxa, Zootaxa 3911 (1), pp. 1-142 : 28-30

Lamelliassus gen. nov.

Type species: Lamelliassus chaingmaiensis sp. nov.

Orange yellow with symmetrical dark brown markings dorsally ( Fig. 5 A, B). Body robust, weakly depressed. Head in dorsal view much narrower than pronotum; crown short, rounded to face, anterior and posterior margins parallel; vertex and frontoclypeus transversely rugose ( Fig. 5 A); face slightly broader than tall; gena broadly rounded, concavely emarginate below eye; rostrum slender, extended slightly beyond front trochanter; anteclypeus flat, parallel-sided through most of length, slighly tapered distad of lorum, apex truncate, even with lower margin of gena; lorum narrow, well separated from lateral and ventral margins of gena, with slightly more than basal half of mesal margin bordering frontoclypeus; frontoclypeus convex; antennal ledge well developed, broad, slightly oblique; lateral frontal suture absent; ocellus large, distinctly mesad of antennal pit and distant from eye. Pronotum strongly convex, with fine transverse rugae; lateral margins long, strongly carinate, evenly divergent posterad. Exposed part of mesonotum and scutellum together distinctly shorter than pronotum, transversely rugose; scutellar suture arched anterad, scutellum weakly convex with apex acute. Forewing venation obscure in basal 2/3; membrane hyaline except near base of costal field and base of clavus; without small black spots; setae present in basal 2/3 but sparse, very short, and inconspicuous; appendix broad, extended to wing apex, slightly narrower than inner apical cell; vein R with ca. 7–8 branches; three closed anteapical cells present; apical cells 1–4 long, parallelsided, progressively longer toward trailing edge of wing, bases not aligned; posterior branch of CuA connected to margin at apex of clavus; clavus truncate apically; texture of inner apical cell same as that of appendix and adjacent apical cell ( Fig. 5 A, B). Front femur with pair of dorsoapical macrosetae and preapical AD macroseta; AM with large distal setae and ca. 8 smaller preapical setae; intercalary row with several scattered setae; AV with 3 macrosetae in basal half; PV with 5 macrosetae; tibia flat and bicarinate dorsally, rows AD and PD 5+5. Mesothoracic femur with two dorsoapical macrosetae and one preapical AD seta; AM, AV, and PD each with three or more preapical macrosetae; tibial rows AD and PD 6+5. Hind femur macrosetae 2+2+1 with antepenultimate seta as large as others; tibial rows PD, AD, and AV with 19, 13, and 13 macrosetae, respectively; tarsomere I without enlarged dorsoapical setae; plantar surface bare except for group of short setae laterally near apex; pecten with 3 platellae.

Male abdominal apodemes poorly developed; laterotergites III – VII enlarged, lamelliform, overlapping each other from front to back; sternite VIII ca. 1.6 times longer than sternite VII, approximately as long as broad, lateral margins roundly tapered posterad, apex convexly produced. Genital capsule with ventral part almost completely concealed by sternite VIII in repose, with only anal tube and part of posterior pygofer margin visible. Pygofer with tergite long, well sclerotized, weakly emarginate distally in dorsal view; with posterodorsal group of several long macrosetae and dense group of short, stout setae closer to posterior margin; acessory lobe present posteroventrally, flaplike, bearing numerous short, stout setae; basolateral setal group absent; anterodorsal margin in lateral view emarginate along intersegmental membrane; posterior margin long and straight, without process; intersegmental membrane between anal tube and atrium of aedeagus not distinctly sclerotized, without setae ( Fig. 19 A). Subgenital plates short, broad, depressed, fused medially at base, free in distal half, without distal teeth or processes; with few long, fine setae along lateral margin preapically and few short setae at apex and preapically along mesal margin ( Fig. 19 B). Valve long, subquadrate, broadly fused to pygofer at base, posterior margin truncate ( Fig. 19 B). Connective shieldlike, stem broad, anterior arms visible but fused by intervening sclerotization ( Fig. 19 D). Style well developed, articulated to connective well below aedeagal atrium, in lateral view with apodeme and apophysis both nearly straight with junction forming obtuse angle; apodeme long, spatulate; apophysis longer than apodeme, apex rounded and spatulate, without angulate projections ( Fig. 19 E, F). Aedeagus simple, tubular, U-shaped in lateral view ( Fig. 19 C), preatrium absent, atrium in posterior view parabolic dorsally, with short ventrolateral lobes; shaft without processes, apex acuminate in lateral view ( Fig. 19 C), bifid in posteroventral view; gonopore preapical on posterior surface with inner surface denticulate ( Fig. 19 F). Female unknown.

Notes. Lamelliassus appears to be most closely related to Trocnadella based on the absence of small dark spots on the forewing and broad forewing appendix, but is distinguishable by its more robust overall form, the mesally apressed subgenital plates, articulated connective and, most remarkably, the lamelliform laterotergites of the male abdomen. To our knowledge, such modified laterotergites have not been reported in other Cicadellidae , except in the related genus Kanchanaburiassus , described above. A similar condition occurs in the related family Membracidae among a few genera of the Neotropical subfamily Heteronotinae ( Deitz 1975). The genus name, a masculine noun, was formed by combining lamell -, referring to the ventral abdominal lamellae, with Iassus , the name of the type genus of the subfamily.

Figures

FIGURE 5. Dorsal and lateral habitus. A, B, Lamelliassus chiangmaiensis sp. nov.; C, D, Siamiassus constanti sp. nov.; E, F, Trocniassus shaanxiensis sp. nov.; G, H, Trocniassus henanensis sp. nov.

FIGURE 19. Lamelliassus chiangmaiensis sp. nov. A. Genital capsule, lateral view; B. Style, lateral view; C. Genital capsule, ventral view; D. Connective; E. Abdomen, ventral view; F. Aedeagus, lateral view; G, Gentalia, ventral view.