Drabescus stilliformis Xu & Zhang 2018, sp. nov.
Creators: name: Xu, Deliang
name: Zhang, Yalin
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Cicadellidae
Drabescus
Drabescus stilliformis

description: Drabescus stilliformis sp. nov.
(Figs 1, 2)
Description. Body length (including tegmina), male: 6.3–6.4mm; female: 7.9–8.1mm.
Body yellowish brown to brown, transverse band on anterior margin of crown and on margins of pronotum, mesonotum and scutellum, ivory (Fig 1. A, C, H). Face dark brown with broad ivory transverse band in middle below eyes (Fig 1. B). Forewing (Fig 1. E, F) with veins dark brown with whitish callosities; subcostal vein and apex of radial vein with dark stripe. Female with indistinct pale transverse medial band across forewings (Fig 1. H).
Head slightly wider than pronotum. Crown (Fig 1. A, C, H) transversely broad; coronal suture (Fig 1. D) distinct; median length approximately a quarter as long as next to eyes; transversely concave subapically, with dense longitudinal wrinkles; concave next to eyes with oblique wrinkles. Ocelli (Fig 1. D) situated on anterior margin of head, visible dorsally; distance to adjacent eyes approximately 2.5 times ocellar diameter; laterofrontal sutures (Fig 1. B, D) reaching corresponding ocelli. Face (Fig 1. B) wider than long; frontoclypeus slightly swollen laterally; broad basally and narrow apically; frontoclypeal suture present; anteclypellus with median longitudinal carina, clypeal suture curved with apex slightly broader than base; gena (Fig 1. B) broad with disc concave, sparsely punctuate. Pronotum shorter than exposed part of mesonotum and scutellum (Fig 1. C), with anterior margin arched; lateral margin short; hind margin concave, with dense wrinkles. Forewing (Fig 1. E, F) crimped at apex of clavus, with four apical cells and three anteapical cells; appendix broad and extending to the wing apex. Profemur (Fig 1. G) with intercalary (IC) row represented by irregular band of fine setae; AM 1 seta enlarged, situated near apex. Metafemur with apical setal formula 2+1.
Male pygofer (Fig 2. J, K) side moderately long and triangular without posterior process; tapering distally, with several macrosetae. Valve (Fig 2. K, L, M) semicircular. Subgenital plate (Fig 2. J, K, L, M) long; wide basally, tapering distally and sharply curved dorsad; with numerous short fine hair-like microsetae arising from lateral margin, irregularly arranged. Style (Fig 2. K, L, M, N) apical process elongate and digitate; lateral lobe prominent process with microsetae. Connective (Fig 2. O) Y-shaped; stem slender and arms robust; stem about as long as anterolateral arms, bifurcate apically. Aedeagal shaft (Fig 2. J, P, Q, R) curved dorsad, with pair of elongate laterobasal processes extending along shaft nearly to apex of shaft; gonopore (Fig 2. P, Q) apical on ventral surface. Segment X (Fig 2. J) short, sclerotized laterally and dorsally.
Female genitalia. Hind margin of 7 th sternite (Fig 1. I) with V-shaped notch and lateral margin truncate. 3 rd valvulae (Fig 1. I) slightly exceeding apex of pygofer.
Material examined. Holotype ♂: Indonesia, Sulawesi Utara, Dumoga-Bone National Park, 0 1 May 1985, Edward’s Camp 664m, at light, coll. J.H. Martin. Paratypes: Indonesia, Sulawesi Utara, Dumoga-Bone National Park, 13♂ 2♀, February 1985; 1♂ 1♀, May 1985, Toraut. nr base camp, ca 200m, M. R. Wilson; 1♀, June 1985, same data as holotype; 1♂, Toraut, 0°34′N, 123°54′E, 6 July 1985, light trap sample, forest, River Tumpah, coll. A. H. Kirk-Spriggs (NMW). All Royal Entomological Society London, Project Wallace, (BMNH except where indicated).
Etymology. The new species epithet originates from the Latin word “ stilla ” for “drop”, referring to the pronotum and scutellum being surrounded by a drop-shaped ivory band.
Remarks. This new species is similar to D. vilbastei Zhang & Webb, 1996 but can be distinguished from the latter by the pygofer side without process (processes present in D. vilbastei); style lateral lobe more pronounced and aedeagus with laterobasal processes nearly as long as the shaft (processes shorter than shaft in D. vilbastei).
description: Published as part of Xu, Deliang & Zhang, Yalin, 2018, Review of Indonesian species of the leafhopper genus Drabescus Stål (Hemiptera: Cicadellidae: Deltocephalinae) with description of two new species, pp. 473-481 in Zootaxa 4524 (4) on pages 474-477, DOI: 10.11646/zootaxa.4524.4.4, http://zenodo.org/record/2610670