﻿Opacoptera Gozmány (Lepidoptera, Lecithoceridae) from China, with descriptions of four new species

﻿Abstract The genus Opacoptera Gozmány, 1978 is reviewed. Four species are described as new: O.condensatasp. nov., O.hybocentrasp. nov., O.introflexasp. nov. and O.longissimasp. nov.Opacopterakerastiodes Park, 2021 is newly recorded for China. Images of adults are provided, along with a key to the males of all the known species.


Introduction
Opacoptera is a small genus classified in the subfamily Lecithocerinae. Gozmány (1978) established the genus for the single species Lecithocera callirrhabda Meyrick, 1936 from China, the type species. Species of Opacoptera are known only from the Oriental Region. Wu and Liu (1992) and Wu (1996) described two Chinese species in the genus, O. flavicana Wu & Liu, 1992and O. ecblasta Wu, 1996. Park and Kim (2021 described an additional species, O. kerastiodes Park, 2021, from Thailand. Opacoptera currently comprises four described species.
The aim of this paper is to review the genus Opacoptera and to describe four new species.
Remarks. The generic characters of Opacoptera were originally defined by Gozmány (1978) based on the type species, Opacoptera callirrhabda (Meyrick, 1936). Wu (1996) gave the female characters of the genus. In this paper, we revised the generic characters including the forewing venation, male and female genitalia after examining all species of the genus. Apices of posterior lobes of juxta extending posteriorly well beyond middle of tegumen (Fig. 17)  Inner margin of base of posterior lobes of juxta with medial, triangular projection (Fig. 15)  Juxta incised in triangle at middle on posterior margin; posterior lobes straight (Fig. 11)  Diagnosis. This species is diagnostic in the male genitalia by the juxta incised at middle in a triangle on the posterior margin (Fig. 11). It is similar to O. condensata sp. nov., and the differences between them are stated in the diagnosis of the latter species.
Distribution. China (Sichuan, Yunnan) (Gozmány 1978;Wu 1996). Remarks. Meyrick (1936) described this species based on five male specimens (one from Shandong, two from Shaanxi and Yunnan, respectively) and placed it in the genus Lecithocera. Clarke (1965) assigned one of the specimens from Yunnan as the lectotype according to the original description. Gozmány (1978) noted that only the two specimens from Yunnan were conspecific. He also hypothesized that they were distinct from Lecithocera, so diagnosed the genus Opacoptera and placed the species therein. Wu (1996) was first to described the female of O. callirrhabda based on specimens with associated males collected at different times and from different localities of Sichuan. According to the description and the drawing given by Wu (1996), the female genitalia of O. callirrhabda has a narrowed ductus bursae and a single signum. However, the female of the species examined in this study from Yunnan is quite different, and we describe it herein.  (Meyrick, 1936) (Meyrick, 1936). It can be distinguished by the forewing having two black patches, CuA 1 stalked with CuA 2 , and ductus seminalis having dense granules; in O. callirrhabda, the forewing has no black patches, CuA 1 and CuA 2 are separate, and the ductus seminalis has no granules.
Male genitalia (Fig. 12). Uncus subcrescent. Gnathos with basal plate bell-shaped, bearing a papillary process at middle on posterior margin; median process wide in basal 1/3, narrowed to distal 2/5, thereafter slender to pointed apex, curved ventrad at distal 1/4 by a right angle. Valva wide in basal 1/4, narrowed slightly to cucullus; cucullus about half length of valva, narrowed slightly to obtusely oblique apex, costal margin shallowly concave except convex at base, ventrobasal process subtriangular, with a rounded apex; costal bar narrow, slightly expanded dorsad medially; sacculus a broad band, about 1/4 length of ventral margin of valva. Saccus rounded on anterior margin. Juxta broadly concave on posterior margin, denticulate along lateral sides of concavity; with a trapezoidal process at middle on anterior margin; posterior lobe strongly horn-shaped, curved outward at middle; posterolateral lobe short, narrow, extending laterally. Aedeagus nearly as long as valva, slightly widened medially, dorsal denticles larger than cornuti; cornuti consisting of 1-3 conic spines.
Etymology. The specific epithet is derived from the Latin condensatus, referring to the dense granules in the ductus seminalis. Wu, 1996 Figs 5, 13 Opacoptera ecblasta Wu, 1996: 12 Diagnosis. This species is similar to O. kerastiodes Park, 2021 both in appearance and male genitalia. It can be distinguished by the third palpomere of the labial palpus with hair-pencils, the heart-shaped uncus and the needle-like posterior lobes of the juxta (Fig. 13); in O. kerastiodes, the third palpomere of the labial palpus is smooth, the uncus is subrectangular, and the posterior lobes of the juxta are horn-shaped.

Opacoptera flavicana Wu & Liu, 1992 Figs 6, 20
Opacoptera flavicana Wu & Liu, 1992  Diagnosis. This species can be distinguished from its congeners by the pale yellowish brown forewing, the juxta without posterior lobes in the male genitalia (Wu and Liu 1992: 681, fig. 2148), and the corpus bursae with a single signum in the female genitalia (Fig. 20).  (Meyrick, 1936) Description. Wingspan 16.0 mm (Fig. 6). Distribution. China (Guizhou, Hunan). Remarks. Wu and Liu (1992) described the species from Hunan, China on a male and four females, and placed it in the genus Opacoptera based mainly on the wing venation. But the species seems distinctive in the genus Opacoptera both in appearance and genitalia as stated in the diagnosis. It probably does not belong to the present genus and the taxonomic status needs further study. Diagnosis. The male genitalia of the new species is similar to that of O. introflexa sp. nov. It can be distinguished by the forewing having CuA 1 and CuA 2 separate and the horn-shaped ventrobasal process of the cucullus; in O. introflexa sp. nov., the forewing has veins CuA 1 and CuA 2 stalked and the ventrobasal process of the cucullus is broadly rounded, thumb shaped.

Opacoptera hybocentra
Description. Wingspan 12.0-13.5 mm (Fig. 7). Head dark brown. Antenna with scape yellowish brown, flagellum pale brownish yellow. Labial palpus pale brownish yellow, third palpomere as long as second palpomere. Thorax and tegula dark brown. Forewing dark brown, with two black patches: one at basal 1/4, elliptical, the other at middle, shape ill-defined; fringe yellowish brown; CuA 1 and CuA 2 separate. Hindwing and fringe pale brownish yellow except yellowish brown around apical area.
Distribution. China (Yunnan). Etymology. The specific name is derived from the Latin hybocentrus, referring to the curved ventrobasal process of the cucullus. Diagnosis. The new species is unique among other species in the genus by having a triangular process at the base of the posterior lobe of the juxta at the inner margin. It is similar to O. hybocentra sp. nov., and the differences between them are stated in the diagnosis of the latter species.

Opacoptera introflexa
Description. Wingspan 13.0-13.5 mm (Fig. 8). Head dark brown. Antenna with scape brownish yellow; flagellum orange yellow. Labial palpus orange yellow except dark brown ventrally on third palpomere; third palpomere as long as second palpomere. Thorax and tegula dark brown. Forewing dark brown, with two, narrow black patches, one at the basal 1/4 and one in the middle, distal 1/3 with diffused black scales; fringe dark brown; CuA 1 and CuA 2 short-stalked. Hindwing and fringe brown.
Distribution. China (Yunnan). Etymology. The specific epithet is derived from the Latin introflexus, referring to the medially curving posterior lobes of the juxta.   (Fig. 9). Diagnosis. This species is distinct among other species by having a clavate valva (Fig. 16). It is similar to O. ecblasta Wu, 1996, and the differences between them are stated in the diagnosis of the latter species.
Remarks. This species was originally described from Thailand based on a single male. It is recorded from China for the first time in this paper. Diagnosis. The new species can be distinguished from its congeners by the ventrobasally serrate cucullus and the apices of the posterior lobes of the juxta extending beyond the middle of the tegumen.

Opacoptera longissima
Description. Wingspan 13.0-14.0 mm (Fig. 10). Head dark brown. Antenna orange yellow, paler distally. Labial palpus orange yellow except third palpomere dark brown ventrally; third palpomere as long as second palpomere. Thorax and tegula dark brown. Forewing dark brown, with diffused black scales distally; with two ill-defined black patches at basal 1/4 and middle respectively; fringe dark brown; CuA 1 and CuA 2 short-stalked. Hindwing and fringe brown; fringe with an orange white basal line.
Male genitalia (Fig. 17). Uncus subrectangular, semicircularly concave on posterior margin; caudal lobe seimiovate. Gnathos with median process wide at base, narrowed to middle, slendered from middle to pointed apex, curved ventrad at distal 1/4 by a right angle. Valva wide at base, narrowed slightly to cucullus; cucullus about half length of valva, narrowed to obtusely rounded apex, costal margin expanded dorsad basally, ventral margin serrate ventrobasally and gently concave at middle; costal bar narrow, slightly arched, triangularly produced at middle on dorsal margin; sacculus narrow basally, widened distally, about 1/4 length of ventral margin of valva. Saccus rounded on anterior margin. Juxta deeply concave in V-shape on posterior margin, with a papillary process at middle on anterior margin; posterior lobe large horn-shaped, extending beyond middle of tegumen apically; posterolateral lobe small, narrowly banded, extending posterolaterally. Aedeagus nearly as long as valva, slightly widened medially, with two dorsal denticles; cornuti consisting of three large needlelike spines.
Female unknown. Distribution. China (Yunnan). Etymology. The specific name is derived from the Latin longissimus, referring to the long posterior lobe of the juxta.