Naevus Knight 1970

Genus Naevus Knight 1970 View in CoL

Naevus Knight 1970 View in CoL Type species: Hishimonus dorsiplaga Heller & Linnavuori 1968 View in CoL

Description. Naevus can be recognized by the following combination of characters:

Body length: 3 − 4.1 mm.

Coloration: very similar to Hishimonus Ishihara and Litura Knight , generally yellow, ivory or silvery white forewings, occasionally with brown patches, particularly, wings at rest with large brown semicircular spot against midlength of commisural margin forming, and conspicuous circular spot along with that of opposite side (fig. 4).

Head: Head as wide as pronotum; face shagreen (fig. 7); crown slightly longer than next to eye, dorsally, anterior margin broadly rounded, somewhat produced and flat, vertex anterior to furrow shagreen, posterior to furrow glabrous, narrowly rounded to face, with shallow transverse furrow between ocelli (fig. 3); frontoclypeus narrow, longer than wide; clypeal suture distinct, arcuate and obsolete medially, postclypeus as wide as long; clypellus narrower than lorum at base, parallel-sided in basal two thirds, slightly expanded at apex, with straight apical margin and slightly produced beyond gena; gena with single fine erect seta close to lateral frontal suture, lateral margin slightly incised and rounded, genal margins concave underneath eyes; ocelli situated on anterior margin of crown very close to eye; mesal margin of eye entire; lateral frontal suture reaching ocellus and directed toward middle of ocelli; lorum widely separated from genal margin at apex, inner margin of lorum bordering postclypeus less than 1/3; Antenna long and its ledge weakly developed, near middle or posteroventral (lower) corner of eye.

Thorax: yellowish green or ivory in colour, pronotum about 2x in length of vertex, with short sides, posterior margin transverse or slightly concave, slightly longer than Scutellum; scutellum wider than long (fig. 3).

Wings: Forewings with, claval veins separate, appendix well developed, inner subapical cell open, outer subapical cell elongate, ends transverse, m-cu2 crossvein and A1 crossvein present, A veins gently curved distally, R1 not confluent with costa (with 3 anteapical cells), A1 − A2 crossvein and r-m1 crossvein present (fig. 4).

Legs: generally straminous; fore femur row AM with AM1; protibia row AD with 1 macroseta, PD row (N, I=1) with 4 setae; hind femur setal formula 2+2+1, setae of penultimate pair set close to each other; hind tibia PV row with setae increasing in size towards apex, AD row with more than 11 macrosetae, AD row 1 − 2 setae between each pair of macrosetae, hind tarsomere with 2 well-developed longitudinal rows of setae on ventral surface; setal areolae on legs dark.

Male genitalia: (fig. 8 − 14) pygofer broadly rounded posteriorly (except N. subparallelus , acutely rounded posteriorly), with stout setae over posterior half, with or without short membranous finger-like projection on mesial edge of posterior margin; subgenital plates tapering posteriorly to membranous fingerlike process, with submarginal uniseriate row of stout setae, becoming multiseriate basally, and marginal row of long filamentous setae; connective Y-shaped, stem about equal in length to branches, short, broad; styles with apical process fingerlike, directed posteriorly, subapical lobe weakly developed or absent; aedeagus with two shafts each with gonopore apically on mesal surface, elongate, broadly curved, ventroposteriorly directed at base then dorsally, with processes, atrium without proceses, strongly produced ventrally.

Differential diagnosis. The genus Naevus is easy distinguished from Hishimonus and Litura by the regular or constant shape of the medial brown spot on forewings (sometimes absent); subgenital plate gradually tapered apically; male pygofer almost rounded; aedeagal shafts ventroposteriorly directed at base; atrium extending ventrad of shafts and atrium without process.