Lethe gemina bicolor Xue subsp. nov.

(Fig. 2)

Lethe gemina: Harada et al. 2005: 24, figs. 1, 2 for ♂, figs. 3, 4 for ♀ from Nanling area, Guangdong; Gu et al. 2018: 53, photos for ♂ ♀ from Nanling National Nature Reserve, Guangdong.

Type material. HOLOTYPE ♂: Nanling National Nature Reserve, 1000 m, Ruyuan, Guangdong, China, 28.VI.2024, leg. Xue Guoxi & Li Fang [Specimen ID E21].

PARATYPES: the same locality and collectors as the holotype. 2♂♂, 14.VII.2023, 27.VI.2024 [Specimen ID E22, Genitalia No. GD75]; 5♀♀, 13.VII.2023, 27.VI.2024 [Specimen ID 2024-41], 27.VI.2024 [Genitalia No. GD76], 27.VI.2024 [Specimen ID E24], 3.VII.2024 [Specimen ID E23].

Diagnosis. Lethe gemina is rare in the field. Literature providing photos and descriptions of the seven known subspecies are listed as follows.

gemina: Lang 2017: 102, pl. XII, fig. 1 for ♂; Wu & Hsu 2017: 459, fig. 10 for ♀.

chekiangensis: Tong et al. 1993: pl. 18, figs. 134, 135 for ♂; Jiang et al. 2001: pl. 51, fig. 26–121 for ♂; Lang 2017: pl. XII, fig. 2 for ♂; Wu & Hsu 2017: 460, fig. 13 for ♂.

gafuri: Shizuya et al. 2005: 32, 38 for ♂; Lang 2017: 103, pl. XII, figs. 3 for ♂, 4 for ♀.

zaitha: Igarashi 2005: 23, fig. 5 for ♂ ♀; Wu & Hsu 2017: 459, fig. 11 for ♂, 460, fig. 12 for ♀.

yao: Sugiyama 1996: figs. 1, 2 for ♂; Monastyrskii 2005: 181, figs. 3a, 3b for ♂; Wang & Tang 2012: 18, pl. 56, figs. 1, 2 for ♂, figs. 3, 4 for ♀; Lang & Ding 2017: 39, figs. 5–8 for ♂ ♀; Lang 2017: 103, pl. XII, fig. 7 for ♂, 8 for ♀; Wu & Hsu 2017: 459, fig. 9 for ♀; Huang 2021: 352, 388, fig. 180 for ♂♂.

shanshanae: Lang & Ding 2017: 39, figs. 1–4 for ♂ ♀; Lang 2017: 103, pl. XII, fig. 5 for ♂, 6 for ♀; Gu & Chen 1997: 148, fig. 123 for ♂ ♀.

yongreni: Huang 2021: 352, 388, fig. 179 for ♂♂; Saito & Inayoshi 2018: 29, 43, fig. 13 for ♂; Osada et al. 1999: 144, pl. 90 for ♀.

Judging from the information provided in the above listed literature and the examined specimens and photos in the present study (Fig. 3), the new subspecies can be distinguished by wing color and wing patterns of both sexes: in the new subspecies, the ground color on the dorsal side of the wings is tawny in the male and dark brown in the female, while in both sexes of the seven subspecies of Lethe gemina (except for the female of yongreni which is unknown), it is fulvous in the nominate subspecies, dirt yellow in chekiangensis (according to Lang 2017: 103, but see the Discussion below), orange in gafuri and zaitha, and greyish in yao, shanshanae and yongreni; the prominent silver color on the ventral side of the wings in the female of the new subspecies obviously differs to other subspecies.

In terms of distribution (Fig. 4), the new subspecies is close to Lethe gemina yao, but it can be distinguished from the latter by the following external characters: 1) in the male, the subapical ocellus on the forewing is vestigial on the dorsal side and much smaller than that of yao on the ventral side; on the dorsal side of the hindwing, ocelli in spaces M 1 and M 3 are well developed, the rings surrounding the postdiscal ocelli are orange, and the pupil of the ocellus in space CuA 1 may be disappeared; 2) in the female, the postdiscal series of ocelli on the dorsal side of the hindwing are surrounded by orange rings, with the two in spaces M 1 and M 3 well developed, and the one in space CuA 1 without pupil; on the ventral side, the silver white area between the postdiscal fascia and the submarginal line is diffused toward wing base and gradually darken, forming a lighter ground color than that of yao.

Judging from the male genitalia (Figs. 5, 6), the following characters of the new subspecies differ to those of Lethe gemina yao: in lateral view (Fig. 5: C, E), the top of the tegumen is flat, the distal part of the uncus is slightly tilted up, and the saccus is shorter; in dorsal view, the apical part of the uncus is laterally expanded (Fig. 5: F); the distal half of the valva is wider in lateral view, and the apical part after the thorn is longer (Fig. 5: A–D, G, H); the suprazonal sheath of the aedeagus is shorter (Fig. 5: D, I).

Since the female genitalia of Lethe gemina have not been described, the following description of the female genitalia of the new subspecies is provided.

Female genitalia (Fig. 7). Papillae anales flabellate in lateral view. Lamella postvaginalis nearly rectangular in ventral view, its central part swollen in lateral view. Lamella antevaginalis flat in lateral view, much wider and longer than lamella postvaginalis in ventral view, basal margin arched. Ductus bursae long and thin. Bursa copulatrix bursiform, membranous, with two signa composed of numerous tiny spinules.

Distribution. Ruyuan (northern Guangdong).

Etymology. The subspecific name “ bicolor ” means that the two sexes of the new subspecies bear different ground color on the dorsal side of the wings.

Discussion. Lethe gemina chekiangensis was described from East Tianmushan of Zhejiang. Based upon a photo of the holotype, Lang (2017: 103) stated that the ground color of chekiangensis is dirt yellow on both surfaces, paler than in the nominate subspecies. Judging from the photos of other specimens (Fig. 3: A, B; Tong et al. 1993: pl. 18, figs. 134, 135; Chou 1994: 342, fig. 4), the ground color of the population from Zhejiang is similar to that of the nominate subspecies, not as pale as that of the holotype of chekiangensis (Lang 2017: pl. XII, fig. 2). A character to separate chekiangensis from the nominate subspecies may be: on the dorsal side of the hindwing, rings surrounding the postdiscal ocelli in spaces M 1 and M 3 are merged into the ground color, but they are present in the nominate subspecies.

Chou (1994: 342) included Zhejiang into the distribution of the nominate subspecies without any explanation. However, Lang (2017: 103) recorded the distributional range of chekiangensis as Zhejiang and Fujian, although no information of any specimen from Fujian was provided. Male specimens from Shunchang and Nanping of northern Fujian were illustrated by Jiang et al. (2001: 46, pl. 51, fig. 26–121) and Wu & Hsu (2017: 460, fig. 13) respectively. Judging from these photos, the ground color on the dorsal side of the wings is darker than that of chekiangensis but similar to the new subspecies described in the present paper, and the rings of the ocelli in spaces M 1 and M 3 on the dorsal side of the hindwing are present, not merged into the ground color as in chekiangensis. Therefore, the population from northern Fujian should not belong to chekiangensis. It can be distinguished from the new subspecies by the combination of the following characters: in the male, the subapical ocellus on the dorsal side of the forewing is better developed; on the dorsal side of the hindwing, the ocelli in spaces M 1 and M 3 and their rings are obscure, not as clearly defined as in the new subspecies; the ground color on the ventral side of the wings is somewhat darker. However, these differences are based upon a comparison of the type series of the new subspecies and photos of only two male specimens from northern Fujian. More materials, especially the female, from northern Fujian need to be examined to determine the taxonomic status of this population.