Lethe lyncus de Nicéville, 1897

Huang, Si-Yao, Lang, Song-Yun & Müller, Günter C., 2024, On the taxonomy of the genus Lethe Hübner (Lepidoptera, Papilionoidea, Nymphalidae, Satyrinae) with description of a new species, Zootaxa 5538 (1), pp. 59-73 : 67-71

Lethe lyncus de Nicéville, 1897

Figs 21–27 , 41–44 , 54 , 60

Lethe lyncus de Nicéville, 1897: 544 , pl. 1, fig. 8; Tytler 1914: 222; H. Huang 1999: 130; Lang 2016b: 216, fig. 4; Lang 2017: 49.

Lethe tristigmata lyncus : Fruhstorfer 1911: 313.

Lethe ocellata lyncus : Evans 1923: 532; Talbot 1947: 181.

Lethe wui H. Huang, 1999: 129 ; figs 1a, 2A, 3A; Lang 2016b: 216, figs 5, 6, 25, 28b; Lang 2017: 49. syn. nov.

Material examined: INDIA: 1 male, Sikkim, (18)86, Möll(er). (leg.), genitalia & androconia preparation No. MfNLe001 ( MfN) ; 1male, Sikkim,Gantok(Gangtok), VIII.1891, G.C.Dudgeon leg.,1905–259, NHMUK015107301 ( NHMUK) ; BHUTAN: 1 male, Bhutan, Bela la , 10000 (ft), 1. 7. (19)22, Bailey (leg.), NHMUK015107302 ( NHMUK) ; CHINA: holotype of Lethe wui H. Huang, 1999 (figs. 20, 35): male, handwritten blue label “ Tibet: Metok (Motuo County) Lage , 2700 m. 1995-VIII.24 H. Huang (leg.)”; white handwritten label “ ī̎-ŝö (Hanmi-Lage) 95-8-24 ”; red handwritten label “HOLOTYPE Lethe wui Huang ” ( CQEC) ; 2 males, altitude 2800 m, 24. VII. 2015, Yunnan, Gongshan, East slope of Mts. Gaoligong , leg. Song-yun Lang, genitalia preparation No. SATY0359 , androconia preparation No. ANDR0069 ( CSYL) .

Diagnosis. Lethe lyncus can be distinguished from L. tristigmata Elwes, 1887 (figs. 28, 29, 45, 55, 61) and L. ocellata ( Poujade, 1885) (figs. 30, 46, 56, 63) by the combination of the following characters: 1) The subapical spots on the forewing underside are tightly conjoined from space 6 to 8 as in L. ocellata , while in L. tristigmata the subapical series of spots are widely separated from each other and situated from space 3 to space 7. 2) The pale margin next to the dark postdiscal band on the forewing underside is well-developed, while in L. tristigmata , it is less developed and in L. ocellata it is totally absent. 3) On the forewing underside, the area between the two dark cell bars of the discal cell is lighter and brighter than the remaining parts, similar to that in L. tristigmata , while in L. ocellata the whole discal cell is uniform in coloration. 4) In male genitalia, the uncus in lateral view is much wider than that in L. tristigmata and L. ocellata . 5) The uncus in dorsal view is widened in the medial section as in L. ocellata , while in L. tristigmata the uncus is generally even in width from the medial to distal section. 6) The gnathos are thicker than those of L. ocellata and sinuated, similar to those in L. tristigmata .

Lethe lyncus also somewhat resembles L. armandina but can be distinguished by lacking the purplish tint from basal to postmedial zone on the underside of hindwing, the shorter androconia and the broader basal section of uncus in the male genitalia in lateral view.

Discussion. Since the original description, the status of this rare taxon has been uncertain for a long time. Fruhstorfer (1911) treated this taxon as a subspecies of L. tristigmata . Later both Evans (1923) and Talbot (1947) considered it as a subspecies of L. ocellata , and subsequently H. Huang (1999) regarded it as a synonym of L. tristigmata . Recently, the senior author examined the specimens of this species held in MfN and NHMUK, and the study of the male genitalia as well as the androconia led to the conclusion that L. lyncus is a bona species different from both L. tristigmata and L. ocellata , and the differences are summarized above.

The descriptions of the male brand in this species differ from each other in several works. Although, in the original description, de Nicéville (1897) mentioned that the male brand was “barely traceable”, Evans (1923) and Talbot (1947) both stated that L. lyncus bore “broken brand from mid v1 to base v4” or “interrupted male brand”, respectively. During the course of the current study, we examined three males of this species together with the syntype photos published in Sheela et al. (2019) ( Fig. 21 ), and we found that the male brand of this species varied from vestigial ( Fig. 22 ) to relatively prominent ( Fig. 24 ) with intermediate individuals connecting both forms ( Fig. 23 ). Therefore, it is probable that the different descriptions of the male brand in historical literatures are caused by the different individuals examined by the authors.

Lethe wui H. Huang, 1999 is sunk as a synonym of L. lyncus in the present study. Since the original description, L. wui was only known from a few individuals captured in Xizang and Yunnan in China as well as Kachin State in northern Myanmar ( Koiwaya & Shizuya 2011), and the relationship between it and L. lyncus remains unclear for the lack of available material of the latter species. Lang (2016b, 2017) indicated that L. wui was probably only a subspecies or synonym of L. lyncus due to the similarity in wing pattern. After examining the specimens of L. lyncus , it turned out that the male genitalia as well as the androconia of L. wui did not show significant difference from those of L. lyncus . The male brand in L. wui is also variable ( Figs 25–27 ), and, taking the specimens of L. lyncus examined in the present study into account, all the individuals together form a complete chain of variation in male brand from vestigial to well-developed, same as the situation of L. jianqingi and L. armandina yanbiana . Therefore, L. wui should be synonymized with L. lyncus (syn. nov.).

Distribution. northeastern India (Sikkim, Manipur), western Bhutan, northern Myanmar (Kachin state), southwestern China (southeastern Xizang, western Yunnan) ( Fig. 55 ).

Figures

FIGURES 21–30. Males of Lethe spp. 21, L. lyncus, syntype, Sikkim, NE India, after Sheela et al. (2019); 22, ditto, Sikkim, NE India (MfN); 23, ditto, Sikkim, NE India (NHMUK, ©The Trustees of NHMUK), left side=upperside, right side=underside; 24, ditto, Bela La, W Bhutan (NHMUK, ©The Trustees of NHMUK), left side=upperside, right side=underside; 25, ditto, holotype of L. wui, Metok, SE Xizang, SW China (CQEC); 26, ditto, Mt. Gaoligong, W Yunnan, SW China (CSYL); 27, ditto, ditto (CSYL); 28, L. tristigmata, Sikkim, NE India (ZFMK); 29, ditto, ditto (MfN); 30, L. ocellata, Mt. Emei, W Sichuan, SW China (CSYL). The black arrows in figs 21 & 23 indicate the male brand.

FIGURES 41–46. Male genitalia of Lethe spp. Depository of the genitalia preparation: 41 & 42 in MfN; 43 & 46 in CSYL; 44 in CQEC; 45 in ZFMK. a=genitalia capsule with left valva removed; b=lateral view of the phallus; c=dorsal view of the distal end of left valva. Scale bar for all figures except Fig. 44.

FIGURES 47–56. Dorsal view of the uncus and tegumen of the male genitalia of Lethe spp. Depository of the genitalia preparation: 47 in CGM; 48, 50, 52, 54b & 56 in CSYL; 49, 51 & 53 in CQMNH; 54a in MfN; 55 in ZFMK.

FIGURES 57–63. Androconia of Lethe spp. Depository of the androconia preparation: 57 in CGM; 58, 59, 60b, 62 in CSYL; 60a in MfN; 61 in ZFMK; 63 in CQMNH;