Taxonomic study of the genus Halolaguna Gozmány (Lepidoptera, Lecithoceridae) from China, with descriptions of two new species

Abstract The genus Halolaguna Gozmány, 1978 is studied in China. Two new species, Halolaguna flabellata sp. n. from Guangxi and Halolaguna discoidea sp. n. from Chongqing, Guangxi and Sichuan are described. The female of Halolaguna guizhouensis Wu, 2012 is reported for the first time. Photographs of adults and genitalia are provided. A checklist of all known Halolaguna species is included, along with a key to the Chinese species.


Introduction
The family Lecithoceridae occurs particularly in the Oriental and Australian Regions, with around 1,200 described species (van Nieukerken et al. 2011). Wu (1997) recorded 206 species of Lecithoceridae from China and Park et al. (2013) listed 74 species of Lecithoceridae from Chinese Taiwan. To date, approximately 290 species of this family have been reported from China.
Halolaguna Gozmány, 1978 is a small genus of the subfamily Torodorinae in Lecithoceridae, which was established by Gozmány in 1978 based on the type species H. sublaxata Gozmány, 1978 from China. Subsequently, Wu (2000) transferred Lecithocera biferrinella Walker, 1864 to Halolaguna, and described H. orthogonia Wu, 2000 from Malaysia;Park (2000) transferred Cynicostola oncopteryx Wu, 1994 to Halolaguna, anddescribed H. palinensis Park, 2000 from Taiwan;Park (2011) further described H. sanmaru Park, 2011 from Thailand;and Wu (2012) described H. guizhouensis Wu, 2012 from Guizhou. To date, Halolaguna includes seven species confined to the Oriental and Palaearctic regions, but little is known about the biology of this genus so far.
Halolaguna is characterized by having an elongate and relatively narrow forewing with M 2 and M 3 coincident, and the valva tapering to the apex in the male genitalia.
Halolaguna is similar to Antiochtha Meyrick, 1905 in both appearance and male genitalia, but can be distinguished by the presence of M 2 in the hindwing, which is absent in Antiochtha. It is also similar to Athymoris Meyrick, 1935 in the venation, but differs in the valva in the male genitalia that is tapering to a pointed apex, whereas the valva is foot-shaped and widened terminally in Athymoris.
We report five Halolaguna species from mainland China in this paper, based on the specimens collected mostly from mountainous regions and natural reserves. Two species are described as new, and the female of Halolaguna guizhouensis Wu, 2012 is described for the first time.

Material and methods
The specimens examined in this study were collected from mountains, botanical gardens and nature reserves in China by light traps. All specimens studied, including the types, are deposited in the Insect Collection, College of Life Sciences, Nankai University, Tianjin, China.
Genitalia dissections were carried out following Li (2002). Photographs of the adults were taken with a Leica stereo microscope M205A plus Leica Application Suite 4.2 software, and genitalia were photographed using a Leica DM750 microscope plus the same software as for adults.

Checklist of Halolaguna species
Halolaguna biferrinella (Walker, 1864)  (Wu, 1994) and H. flabellata sp. n. in the forewing shape and the male genitalia, but can be separated from these by the juxta with thin claviform postero-lateral lobes slightly longer than the juxta, and the aedeagus with a discal process apically. In H. oncopteryx (Wu, 1994) and H. flabellata sp. n., the postero-lateral lobes of the juxta are short finger-shaped, about 1/2 length of the juxta, and the aedeagus is absent of discal process apically.
Description. Adult (Figs 1a, 2a) with wing expanse 16.5-18.0 mm. Head yellowish white, with scattered brown scales. Antenna yellowish white, scape brown on ventral surface, flagellum with pale brown annulations. Labial palpus yellowish white, with scattered brown scales; second segment with appressed scales; third segment slender, about same length as second. Thorax brown, tegula purple brown. Forewing with costal margin almost straight from basal 1/4 to 3/4; apex protruding triangularly; termen oblique, concave below apex; ground color deep grayish brown; subapical spot yellowish white, nearly triangular; discal and discocellular spots blackish brown, nearly rounded; a yellowish white line extending from costal 2/5 to above fold, edged with blackish brown scales along inner margin, curved triangularly inward to outer margin of discal spot; cilia blackish brown, yellowish white basally; venation: R 3 stalked with R 4+5 for basal half of its length, R 4 and R 5 stalked for 2/3 length, R 5 to termen, M 1 and R 3+4+5 from upper angle of cell, M 2 absent, M 3 from above lower angle of cell, CuA 1 and CuA 2 shortly stalked at base, from lower angle of cell, cell closed. Hindwing and cilia grayish brown, yellowish white basally; venation: Rs and M 1 stalked for 2/5 length, M 3 and CuA 1 stalked for about 1/3 length, remote from M 2 , cell close partly. Fore leg with ventral surface brown, dorsal surface yellowish white, mottled brown scales, tarsus yellowish white on distal 1/3; mid leg yellowish white, mottled brown scales on ventral surface; hind leg blackish brown, yellowish white on dorsal surface of tibia and on distal half of tarsus.
Female genitalia (Fig. 4a): Eighth sternite with caudal margin deeply concave in U shape at middle, bearing dense setae laterally. Posterior apophyses about twice length of anterior apophyses. Antrum inconspicuous. Ductus bursae long and heliciform, about four times length of corpus bursae, slightly narrow basally, with numerous thumbtack-shaped spinules ranging from basal 1/4 to 1/2; ductus seminalis slender and long, arising from basal 1/4 of ductus bursae. Corpus bursae oval; signum nearly oval, placed at middle of corpus bursae, margined with teeth anteriorly and posteriorly, medially concave, forming a broad and flat central groove.
Distribution. China (Chongqing, Guangxi, Sichuan). Etymology. The name of this species is derived from the Latin adjective discoideus (discal), in reference to the discal process of the aedeagus at apex. Diagnosis. This species is similar to H. oncopteryx (Wu, 1994) superficially and in the male genitalia, but can be separated from the latter by the valva with a blunt apex lacking an apical spine, the juxta nearly rounded, and the apex-rounded aedeagus with two sclerotized plates. In H. oncopteryx, the apex of the valva has a strong apical spine, the juxta is nearly square, and the apex-pointed aedeagus has one sclerotized plate.

Distribution. China (Guangxi).
Etymology. The specific name of this species is derived from the Latin adjective flabellatus (flabellate), in reference to the basally fan-shaped uncus. Diagnosis. Adult (Fig. 1c) with wing expanse 14.0-15.0 mm. This species is similar to H. sublaxata Gozmány, 1978 superficially by sharing small and rounded discal spot and relatively large fold and discocellular spots. It can be separated from the latter by the valva broadly rounded apically, the relatively short gnathos slightly shorter than the uncus, and the juxta with postero-lateral lobes shorter than the juxta in the male genitalia (Fig. 3c). In H. sublaxata, the valva is narrow and thin apically, the slender gnathos is distinctly longer than the uncus, and the postero-lateral lobes of the juxta are longer than the juxta.

Halolaguna guizhouensis
Female genitalia (Fig. 4b): Eighth sternite bearing dense setae, with caudal margin slightly emarginated at middle. Anterior apophyses about 3/4 length of posterior apophyses. Ductus bursae about four times length of corpus bursae, long and heliciform; ductus seminalis slender, arising from basal 1/8 of ductus bursae. Corpus bursae nearly rounded; two small papillate signa placed posteriorly, with dense granules; one big rhombic signum placed at middle of corpus bursae, with a nearly triangular horizontal plate arising medially.
Distribution. China (Chongqing, Guangdong, Guangxi, Guizhou). Remarks. Halolaguna guizhouensis was described by Wu (2012) based on two male specimens from Guizhou. The valva of this species is not distinctly narrowed distally, whereas the valva of its congeners is obviously narrowed to pointed apex. However, the venation of this species is consistent with that of the type species. The female is described here for the first time.
Distribution. China (Chongqing, Fujian, Guangxi, Sichuan, Taiwan, Yunnan, Zhejiang). Gozmány, 1978 Figs 1e, 1f, 3e, 4d Halolaguna sublaxata Gozmány, 1978: 238 Gozmány, 1978 can be separated from its congeners by the slender gnathos longer than uncus, and the valva slightly curved ventrad before apex in the male genitalia (Fig. 3e). Halolaguna sublaxata is similar to H. guizhouensis in the female genitalia by the corpus bursae sharing three signa, but can be separated from it by the position of the signa: in H. sublaxata, one large sub-triangular signum placed posteriorly, one small triangular signum below it, and the shuttle-shaped signum placed anteriorly ( Fig. 4d); in H. guizhouensis, two small papillate signa placed posteriorly, and the third large rhombic signum is placed at middle of the corpus bursae.