Evacanthus extremus Walker
Creators: name: Viraktamath, C. A.
name: Webb, M. D.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Cicadellidae
Evacanthus
Evacanthus extremus

description: Evacanthus extremus (Walker)
Figs 5 A, 6 U–Y, 10 B, 11 M–P, 26 A–F.
Tettigonia extrema Walker 1851: 761.
Euacanthus extremus (Walker): Distant 1908: 227–228, fig. 142. Evacanthus extremus (Walker): Metcalf 1963: 25; Rao 1990: 28 –30, fig 6 a–h.
Ochraceous. Large transverse spot on disc of vertex black, in female sunken spot mesad of eye on anterior margin of head fuscous. Pronotum with median stripe that is narrowed caudally and not reaching hind margin, and large spot on either side, black. Mesonotum black. Forewing stramineous to ochraceous with one longitudinal stripe on corium and another on clavus, piceous. Thoracic pleura and sterna infuscated. Legs ochraceous, hind tibiae with spines piceous. First two visible sterna piceous.
Pronotum broader than head, with shallow transverse depression on anterior half.
Male genitalia. Pygofer lobe with basal fracture, posterodorsal angle lobe-like, ventral process near apex dark pigmented, distally tapered, with two denticles on anterior margin near a point where it separates from the lobe. Subgenital plate longer than pygofer, with numerous hair-like setae. Style short, stout, apex of apophysis footshaped with well developed heel, toe poorly developed. Connective Y-shaped, stem 1.5 times as long as arms. Aedeagus large, with serrated crest-like ridge ventral margin basally, dorsolateral lobes large, with long processes exceeding ventral margin of shaft, in posterodorsal view processes and shaft extending to same height; ventral extension of atrium well developed, shaft ventral margin grooved, with flange-like process, gonopore apical. Segment X well developed with ventral marginal sclerotized, pigmented and serrated margin.
Female genitalia/ Posterior margin of seventh sternite with small, convex lobe medially.
Measurements. Male 6.1–6.9 mm long, 1.6 mm wide across eyes and 1.7 mm wide across eyes. Female 7.2– 7.6 mm long, 1.7–1.8 mm wide across eyes and 1.8–1.9 mm wide across hind margin of pronotum.
Material examined. INDIA: Holotype, (head and pronotum detached, placed on a separate card, abdomen missing) ‘ Type (green edged disc)” “48 134” “N. India ” (BMNH); 1 specimen (with head and pronotum missing) Kashmir, Gulmarg, 17.viii.1931, Fletcher coll., B. M. 1932-13 (BMNH). Himachal Pradesh: 1 ♂, 15 Km NE Manali, 2348 m, 12.x.1979, C.A. Viraktamath; 1 ♀, Manali, 1828 m, 11.x.1979, C.A. Viraktamath; 1 ♀, Kufri, 2600 m, 15.x.1979, C.A. Viraktamath; Sikkim: 1 ♂, 2 ♀, Gangtok, 1759 m, 8.vi.2005, C.A. Viraktamath; 1 ♀, West Bengal, Kalimpong, 1780 m, 27.x.1981, C.A. Viraktamath (UASB).
Remark. Originally described from a single specimen (holotype) with the following data: “a. North India; from Mr. Warwick’s collection”. The label data “48 134” refers to the following entry in the BMNH register for 1848 134: “N. India Almorah Mr Warwick”. This species can be easily recognized by its characteristic coloration of the pronotum and forewings. From E. repexus, it can be recognized by the peculiar pygofer process and by the dorsally produced processes of the lateral lobes of the aedeagal shaft and by the caudally grooved shaft.
description: Published as part of Viraktamath, C. A. & Webb, M. D., 2018, Revision of the evacanthine leafhoppers (Hemiptera: Cicadellidae: Evacanthinae) of the Indian subcontinent, pp. 1-78 in Zootaxa 4386 (1) on pages 18-19, DOI: 10.11646/zootaxa.4386.1.1, http://zenodo.org/record/1195886