Colias thrasibulus angustomarginata, Huang & Song, 2022

Huang, Hao & Song, Kui, 2022, A review of the genus Colias Fabricius, 1807 (Lepidoptera: Pieridae) from Qinghai with descriptions of a new subspecies of Colias thrasibulus Fruhstorfer, 1910, Zootaxa 5105 (4), pp. 451-489 : 462-463

Colias thrasibulus angustomarginata ssp. n.

( Figs. 23 , 26 , 42–43 , 45–46 , 48 –50, 58, 67)

Type material. Holotype ( Fig. 23 - P 1 ): ♂, CHINA: Qinghai province, Haixi Mongol and Tibetan Autonomous Prefecture , Dulan County, ca 50 km SW. of the county, 4000–4100m, 28.VII.2021, K. Song leg., deposited in SNUC . Paratypes: 15 ♂♂, 3 ♀♀ (13 ♂♂, 2 ♀♀ in CSK, 2 ♂♂, 1 ♀ in CHH), same locality as holotype, 14.VII. & 28–29.VII. 2021, K. Song leg ..

Male holotype description. Length of forewing: 23 mm. Eye smooth. Antenna dark brown above and pale greyish brown below, with club mostly blackish brown, and with shaft obscurely segmented by pale scales. Body above black, clad with long yellowish setae, below densely clad with yellow scales. Frons and palpi clad with yellow scales, mixed with pale yellow and grayish setae. Legs clad with yellow scales, mixed with yellow setae. Both wings same shaped as in other two subspecies.

Wing-pattern generally as in other two subspecies. Ciliae pale yellow on both wings both sides, mixed sparsely with pink ones.

Male genitalia as in other two subspecies, not separable from most of the other Colias species.

Description of male paratypes. Length of forewing: 23– 26mm, mostly 24– 25mm. Ground color of wings upper side pale yellow, occasionally whitish (Specimen P2). Individual variations mainly found in marginal markings on forewing upper side and postdiscal fasciae on both wings upper side.

Description of female paratypes. Length of forewing: 23- 26mm. Upper side ground color more whitish than in males.

Etymology. The specific name refers to the narrower marginal markings on forewing upper side of the new subspecies.

Diagnosis. This new subspecies can be distinguished from ssp. thrasibulus and ssp. fasciata by the following combination of characters: 1) forewing upper side marginal markings, especially the one on vein 5, constantly narrower than in other subspecies; 2) size generally much larger than in ssp. thrasibulus , slightly larger than in ssp. fasciata ; 3) forewing upper side postdiscal fasciae less developed than in other subspecies, duller and narrower, often more or less interrupted by veins; 4) hindwing upper side postdiscal fasciae usually obsolete (invariably well developed in ssp. fasciata ); 5) hindwing upper side discal area paler than in ssp. fasciata , not so black-dusted.

Remarks. Only two subspecies of Colias thrasibulus were considered as valid in Grieshuber et al’s (2012) revision and Grieshuber’s (2014) Guide book: ssp. thrasibulus known from Ladakh Range (Kardung La and Chonging Valley, N. or NW. of Kardung La- TL of thrasibulus ), Zanskar Range (Taglang La - TL of zanskarensis; Nimaling; vicinity of Morari Lake), E. Karakorum Range (Sasser La, Shimshin Jilga - Cretschmar, [1935]), W. Tibet (Zhabu, Rebang, Ritu - Lee, 1982 & Wu, 2010; Yanhu, Gejie - Verhulst, 2001; W. of Paryang - Grieshuber, 2014) and C. Tibet (S. of Namco Lake - Hoshiai, 1996); and ssp. fasciata known only from Yushu, SE. Qinghai. C. thrasibulus zanskarensis was retained by Verhulst (2001) as good subspecies for the populations from Zanskar Range and W. Tibet, but was regarded by Grieshuber et al. (2012) as synonym of ssp. thrasibulus as “it is within the range of variation of nominotypical C. thrasibulus ”. It is difficult to sort the population from S. of Namco, C. Tibet, as it is intermediate between ssp. thrasibulus and ssp. fasciata in distribution and wing-characters. Ssp. fasciata has only slight difference from ssp. thrasibulus in the darker discal area on hindwing upper side, however, the newly collected specimens of ssp. fasciata from Yushu confirm that this slight difference is rather constant. It is possible that ssp. fasciata is only the end of a cline of nominotypical C. thrasibulus . On the other hand, the new subspecies, angustomarginata appears to produce a entirely different phenotype with large size and obsolete black markings and suffusion on the wings upper side.

The zoogeographical pattern of Colias thrasibulus recalls that of Hipparchia autonoe (Esper, 1783) ( Nymphalidae : Satyrini ) in Tibetan plateau: H. autonoe changes a little from W. Tibet ( ssp. mabcha Markhasiov, 2021 ) to Yushu, SE. Qinghai ( ssp. songkui Lang, 2019 ), but turns to be much brighter at Dulan-Balong areas, C. Qinghai ( ssp. arcellae Sbordoni, Bozano & Cesaroni, 2018 ).

Figures

FIGURE 42. ♂ genitalia and 8th tergum (with superuncus) in lateral view at same scale. Scale bar = 1 mm.

FIGURE 43. 8th tergum in dorsal view at same scale to show superuncus. Scale bar = 1 mm.

FIGURE 45. ♂ genitalia in dorsal view at same scale. Scale bar = 1 mm.

FIGURE 46. Ring in lateral view and scaphium in ventral view at same scale. Scale bar = 1 mm.

FIGURE 48. Phallus in lateral view and coecum-process in full-face view at same scale. Scale bar = 1 mm.

FIGURES 21–23. Habitus of Colias taxa ♂♂ & ♀♀ at same scale (Upper side only). 21—Colias thrasibulus thrasibulus; 22—Colias thrasibulus fasciata; 23—Colias thrasibulus angustomarginata. Scale bar = 1 cm.

FIGURES 24–26. Habitus of Colias taxa ♂♂ & ♀♀ at same scale (Underside only). 24—Colias thrasibulus thrasibulus; 25—Colias thrasibulus fasciata; 26—Colias thrasibulus angustomarginata. Corresponding to figs. 21-23. Scale bar = 1 cm.

FIGURES 1–3. Habitus of Colias taxa ♂♂ & ♀♀ at same scale (Upper half- upper side; lower half- underside). 1—Colias adelaidae adelaidae; 2—Colias arida cakana; 3—Colias wanda wanda. Serial number unique for each specimen. Scale bar = 1 cm.