Idioscopus nitidulus (Walker)

VIRAKTAMATH, C. A. & YESHWANTH, H. M., 2024, Arboreal eurymeline leafhoppers (Hemiptera: Cicadellidae: Eurymelinae) of the Indian subcontinent with description of new genera and eight new species, Zootaxa 5462 (1), pp. 1-125 : 48-49

Idioscopus nitidulus (Walker)

Figs 24A–H , 59H , 61J , 67A–D , 73 CD.

Iassus nitidulus Walker 1870: 252 .

Idioscopus nitidulus (Walker) : Maldonado-Capriles 1973: 181, figs. 1–5.

Idiocerus niveosparsus Lethierry 1889: 252 . Maldonado-Capriles 1973: 181.

Idiocerus incertus Baker 1924d: 367 nom. nov. pro maculatus Distant 1912 nec Melichar 1896.

Idioscopus freytagi Ahmed, Naheed & Ahmed 1980: 224–225 figs.3A–H.

Idioscopus karachiensis Ahmed, Naheed & Ahmed 1980: 222–224 , figs 2A–H.

Diagnosis. Crown and pronotum brown to dark brown but without any round spots, face with patch of dark brown surrounding ocelli, mesonotum with basal triangles and a median spot, dark brown, forewing with ivory band across basal area and another near claval apex (at least the veins are ivory). Apical segment of labium in male expanded. Forewing with 3 subapical cells. Male genitalia with style somewhat quadrangular slightly distad of articulation with connective, apophysis with a prominent tooth on ventral surface at midlength.Aedeagus with shaft of moderate width both in lateral and ventral view, apical processes unequal, the shorter process being almost 0.25 as long as longer process, latter almost as long as shaft in lateral view, apex of shaft rounded.

Description. Female. Sternite VII broad about 2.8× as wide as long medially, abruptly narrowed in basal 0.33, then slightly gradually narrowed, posterior margin almost straight wih median short concave excavation ( Fig. 61J ). Valvula I slightly curved dorsally in mid region, distally narrowed, strigae short occupying less than half width of valvula and sculptured area occupying almost distal half length ( Figs 67A,B ). Valvula II straight, with toothed area distinctly convex, prominent, teeth triangular slightly widely spaced, toothed area occupying distal 0.4 length ( Figs 67 CD).

Material examined. INDIA: West Bengal: Type ♂, Calcutta, Idioscopus niveosparsus Leth. (NMNH) . Several male and female pecimens from various parts of India collected on mango, Mangifera indica L.

Remarks. This species was referred to as Idioscopus niveosparsus ( Lethierry 1889) till Maldonado-Capriles (1973), studied the type of Iassus nitidulus Walker 1870 and suggested that it is the senior synonym of the species and also transferred it to the genus Idioscopus . This is the most serious pest of mango among the Idiocerini breeding both on young leaves and inflorescences (Viraktamath 1989). It is found in the entire Oriental region and also invasive in Australia (Fletcher & Dangerfield 2002). Among the species of Idioscopus in the Indian subcontinent, this species can be easily recognized by the ivory markings on the forewings and by the male genitalia. This species is very similar to the Thai species, Idioscopus chumphoni Hongsaprug (1992) but differs in the markings on the face and also in the shape of the aedeagus and its processes. In I. nitidulus , white markings on the face surrounded by the brown patch are adjacent to the ocelli whereas in I. chumphoni they are ventrad of the ocelli and the dorsal surface of aedeagus in the former is smooth without subapical prong-like processes that are present in the latter. In addition, the longer pair of aedeagal shaft processes are longer than aedeagus in lateral view in I. chumphoni but shorter than the shaft in I. nitidulus .

Figures

FIGURES 24A–H. Idioscopus nitidulus (Walker): type female, Idiocerus niveosparsus Lethierry, a junior synonym of I. nitidulus: A–B, habitus, dorsal and lateral views; C, face; D, label data; E, face, male with expanded tip of labium; F, male genital capsule, lateral view; G, style, connective and aedeagus, lateral view; H, styles, connective and aedeagus, ventral view.

FIGURES 61A–R. Idiocerini of the Indian subcontinent, female sternite VII: A, Idiocerus cedarae; B, Metidioceus deodarae; C, M. gnezdilovai; D, Idiocerus sharmai; E, Idioscopus bimaculatus; F, I. clypealis. G, I. confuscous; H, I. irenae; I, I. nagpurensis; J, I. nitidulus; K, I. pretiosus; L, I. shillongensis; M, I. virescens; N, Jogocerus freytagi; O, Keralus webbi; P, Matangia capriliana; Q, M. inidca; R, M. thapai.

FIGURES 67A–P. Idiocerini of the Indian subcontinent, female valvula I, magnified view and valvula II, magnified view:A–D, Idioscopus nitidulus; E–H, I. pretiosus; I–L, I. shillongensis; M–P, I. virescens.

FIGURES 73A–E. Idiocerini and Megipocerini of the Indian subcontinent in their natural habitats: A, adult Idioscopus nagpurensis congregation on under surface of mango leaf; B, Amritodus quinquepunctatus on bark of mango tree; C, Idioscopus nitidulus nymphs feeding on mango fruit; D, I. nitidulus adult on mango leaves; E, Busonia manipurensis sp. nov. adults and nymphs attended by ants.

FIGURES59A–L. Idiocerini andMegipocerini of the Indiansubcontinent,forewings:A,Balocha astuta; B,Amritodusatkinsoni; C, Bellacerus bellus; D, Busoniomimus manjunathi; E, B. mudigerensis; F, Idiocerus cedarae; G, Idioscopus bimaculatus; H, Idioscopus nitidulus; I, Jogina robustipennis; J, Jogocerus freytagi; K, Keralus webbi; L, Matangia capriliana.