Diramus Wang & Zhang

Wang, Yang, Wei, Cong & Zhang, Yalin, 2013, Diramus, a new genus of the leafhopper subfamily Evacanthinae (Hemiptera: Cicadellidae), with description of three new species from Thailand, Zootaxa 3640 (3), pp. 473-478 : 474

Diramus Wang & Zhang , gen. nov.

Type species: Diramus khaokus sp. nov.

Description. Medium-sized leafhoppers measuring 5.2–5.6 mm in length (including tegmen), predominantly dark brown or black, symmetrically marked with yellowish green or white on vertex, scutellum and forewing. Head ( Figs 1, 4, 6, 9, 11, 14 ) conically produced in dorsal view; vertex slightly longer than distance between eyes, about as long as scutellum; lateral margin carinate, median longitudinal carina strong, submarginal carina mesad of corresponding ocellus anteriorly; area between median carina and submarginal carina concave, with longitudinal striations. Ocellus ( Figs 4, 9, 14 ) located about midway between eye and apex of vertex. Face ( Figs 3, 8, 13 ), including eyes, longer than wide, mostly blackish ochreous; frontoclypeus broadened and swollen at base, with black median longitudinal carina and oblique lateral striations; lorum nearly reaching apex of clypellus. Pronotum ( Figs 4, 9, 14 ) broad, wider than head, black. Scutellum triangular, about as long as pronotum, with transverse depression distinct, anterior half black or dark brown and posterior half whitish. Forewing ( Figs 5, 10, 15 ) with veins slightly prominent, R1a present. Front femur row AV with two enlarged basal setae and ca. 8 shorter setae more distad, row PV with ca. 8 short setae, intercalary setae absent, other rows undeveloped; tibia with dorsal surface rounded, row AV with ca.16 setae with more distal setae progressively larger. Middle femur with few fine basal setae in AV and PV; tibia row AV with 8 enlarged basal setae and ca. 8 shorter setae more distad. Hind femur macrosetal formula 2+1+1; tibia with ca. 25, 11, 15, and 30 setae in rows PD, AD, AV, and PV, respectively; tarsus elongate, tarsomere I longer than II and III combined, with pair of dorsoapical setae and 2 longitudinal rows of plantar setae; pecten of tarsomeres I and II each with four tapered setae.

Male pygofer ( Figs 16, 21, 25 , 31–33 ) with short and slender ventral process arising near base; caudal margin of male pygofer slightly membranous and somewhat transparent. Subgenital plate ( Figs 20, 25, 30 ) elongate, ventromedial row of macrosetae regularly distributed, row of elongate fine setae along outer submargin and some long microsetae near apex. Aedeagus ( Figs 17, 18, 22, 23, 27, 28 ) recurved dorsally in lateral view, with bilobed, lamellate dorsal apodeme subbasally; aedeagal shaft membranous dorsally and ventrally, well sclerotized laterally and forming pair of slender apical processes; gonopore subapical. Style ( Figs 19, 24, 29 ) with footlike apex of apophysis having elongated lateral angle. Connective ( Figs 19, 24, 29 ) Y-shaped, stem much longer than arms.

Etymology. The name of the new genus refers to the paired apical process of aedeagus.

Distribution. Thailand.

Remarks. The new genus is very similar to Bundera Distant externally, but it can be distinguished from the latter by: 1) male pygofer side with ventral process ( Figs 16, 21, 25 , 31–33 ), unlike the pygofer side of Bundera , which is curved inwards and elongated but not forming a process; 2) aedeagus bifurcated subapically, forming a pair of slender apical processes ( Figs 17, 18, 22, 23, 27, 28 ), while the apex of the aedeagus in Bundera is tubular and without an apical process; 3) aedeagal shaft in lateral view ( Figs 18, 23, 28 ) without ventral process, while the aedeagus in Bundera usually has a triangular, lamellate process ventrally (Li & Wang, 1996). The type species of Bundera ( B. venata ) was originally erected based on a female. Li & Wang (1996) described the male of this species for the first time, but they did not explain how they determined the correct association between Distant’s female type to the male they examined. Therefore, the identity of B. venata and the genus Bundera needs to be clarified further.

Figures

FIGURES 1 – 15. Male, habitus, face, head and forewing. 1 – 5: D. khaokus sp. nov.; 6 – 10: D. nigromaculatus sp. nov.; 11 – 15: D. uncatus sp. nov.

FIGURES 16 – 30. Male genitalia. 16 – 20: D. khaokus sp. nov.; 21 – 25: D. nigromaculatus sp. nov.; 26 – 30: D. uncatus sp. nov.; 16, 21, 26: male pygofer, lateral view; 17, 22, 27: aedeagus, lateral view; 18, 23, 28: aedeagus, ventral view; 19, 24, 29: connective and style, dorsal view; 20, 25, 30: subgenital plate, ventral view.

FIGURES 31 – 33. Male pygofer side. 31: D. khaokus sp. nov.; 32: D. nigromaculatus sp. nov.; 33: D. uncatus sp. nov.