Capila lineata lineata Chou & Gu, 1994

Xue, Guoxi, Xie, Yunxiao, Shen, Guangcai, Li, Xiaojuan, Li, Meng & Guo, Yingcheng, 2024, Study on the intraspecific variation of Capila lineata lineata Chou & Gu, 1994, with some taxonomic notes on the related taxa (Hesperiidae, Pyrginae), Zootaxa 5446 (4), pp. 573-580 : 575-579

Capila lineata lineata Chou & Gu, 1994

Capila lineata Chou & Gu, 1994 , In: Chou 1994: 772, 700. Type locality: Hainan; Gu & Chen 1997: 302 (description), 303 (photos of male adult); Fan et al. 2003: 59 (comparative description); Fan & Wang 2004: 153 (distribution); Wu & Hsu 2017: 1289 (description, bionomics, distribution), 1291 (photos of male adults).

= Capila lineata irregularis Devyatkin & Monastyrskii, 2002: 141 . Type locality: Pu Hoat Nature Reserve, Nghe An Province, Vietnam; Monastyrskii & Devyatkin 2016: 71 (distribution). syn. n.

= Capila neolineata Fan, Wang & Huang, 2003: 58 . Type locality: Ruyuan County, Guangdong Province, China; Yuan et al. 2015: 130 (description, figure for female genitalia). syn. n.

Historical review. Based upon one male specimen from Hainan, China, Chou & Gu (in Chou, 1994) described Capila lineata as a new species. They compared the wing pattern of the new species with that of C. pennicillata (de Nicéville, [1893]) by providing a black-and-white figure ( Chou 1994: 772, fig. 77), and stated that in C. lineata the ‘anterior portion (of the white oblique band on the forewing) surpassing the vein above the cell’. However, judging from the wing pattern, the wing of C. pennicillata they used in the figure belongs to a female; and, the wing pattern of the new species in the black-and-white figure is inconsistent with that in the color photos of the holotype shown in the same book ( Chou 1994: 700): in the color photos, the white band on the forewing, as described in the accompanying Chinese paragraph (where the gender of the specimen was incorrectly recorded as female), does not extend into the costal area on both dorsal and ventral side. In addition, although a hand drawing of the male genitalia of C. lineata was provided ( Chou 1994: 772, fig. 78), the authors did not give a description or explain the differences in male genitalia of C. lineata and C. pennicillata . Later, Gu & Chen (1997: 302, 303) illustrated the holotype of C. lineata again, but in the text the gender was wrongly recorded as female as in Chou (1994: 700), and the authors of the species were erroneously written as ‘Liu et Gu’; meanwhile, they provided photos of a female of C. pennicillata insularis (Joicey & Talbot, 1921) ( Gu & Chen 1997: 303, fig. 466), which is actually a male.

Two years later, Devyatkin & Monastyrskii (1999) described Capila lineata magna with one male and one female specimen from the southern area of central Vietnam as type specimens. They employed the following characters to distinguish magna from the nominate subspecies: ‘larger size; forewing apical spots vestigial; forewing band on the upperside not continued to costa; hindwing underside without dark spots’. However, some of these differences are debatable: firstly, Chou & Gu did not mention the measurements of the holotype of C. lineata ( Chou 1994) ; secondly, according to the color photos of the holotype ( Chou 1994: 700, fig. 8), the band on the forewing of C. lineata does not continue to costa; thirdly, the ventral side of magna was not shown, while the dark spots on the ventral side of the holotype of C. lineata are very blurred ( Chou 1994: 700, fig. 8). Therefore, it seems that the main difference between the two taxa is the development degree of the forewing subapical spots in the male. Actually, there are more noteworthy differences: on the ventral side, ‘forewing band narrowly continued above radius to costa’ in magna ( Devyatkin & Monastyrskii 1999: 157) but not continued to costa in lineata ( Chou 1994: 700, fig. 8); the edge of the forewing band is smooth in the male of magna ( Devyatkin & Monastyrskii 1999: pl. XII, fig. 3) but ragged in the male of lineata ( Chou 1994: 700, fig. 8). However, Devyatkin & Monastyrskii (1999) did not use these as diagnostic characters.

Subsequently, Devyatkin & Monastyrskii (2002) described another subspecies, viz. Capila lineata irregularis from the northern part of central Vietnam, based upon two male specimens which bear five subapical spots and an irregular forewing band. Meanwhile, they stated that ‘the rank of ssp. magna may be suggested to be raised to species level’ considering the characters in its wing pattern and male genitalia which are different from those of C. lineata ( Devyatkin & Monastyrskii 2002: 142) . However, at that time materials were too few for them (totally five specimens known for the three taxa) to clarify the variability of each subspecies.

The situation became more complicated with the publication of Capila neolineata Fan, Wang & Huang, 2003 from northern Guangdong, China. Ignoring C. lineata magna and C. lineata irregularis , its authors compared the male holotype with the illustrations and descriptions of C. lineata in Chou (1994) and Gu & Chen (1997), and found the following diagnostic characters for C. neolineata : ‘larger in size; the slant white discal series on forewing with spots much broader, with 2 white spots in front of the cell; the subapical series on forewing with the third and the fourth spots shifted outwardly; the upper branch of valva slightly longer’ ( Fan et al. 2003: 59). Bewilderingly, in the Chinese abstract of the same paper, the diagnostic character in male genitalia of C. neolineata was described as ‘the lower branch of valva is slightly longer (than that of C. lineata )’ ( Fan et al. 2003: 59). Either way, figures of the male genitalia of C. neolineata ( Fan et al. 2003: 59, fig. 2) and C. lineata lineata ( Chou 1994: 772, fig. 78) are rather similar. As to wing patterns, the discal band on the forewing of C. neolineata is more similar to that of C. lineata irregularis . Moreover, judging from the photos in the original paper ( Fan et al. 2003: 59, fig. 3), the female genital structures of the paratype of C. neolineata seem to be similar to those of C. lineata magna ( Devyatkin & Monastyrskii 1999: 181, fig. 1-E) except for the shape of the distal edge of lamella postvaginalis. However, in Yuan et al. (2015: 130), a hand drawing of the genitalia of a female C. neolineata , which is from the type locality of the species, shows nearly the same characters as those of C. lineata magna ( Devyatkin & Monastyrskii 1999: 181, fig. 1-E). Wu & Hsu (2017: 1291, 1292) exhibited photos of one male C. lineata from Longmen, central Guangdong, a locality not far from the type locality of C. neolineata , further indicating a questionable status of the latter species.

As reviewed above, the relationship of the four taxa has been an unresolved issue for two decades.

Intraspecific variation of Capila lineata lineata . Based upon the results of molecular analysis and morphological study, the intraspecific variation of the nominate subspecies from Hainan can be summarized as follows:

In the male, the length of the forewing is 25–28 mm (n = 54). On the dorsal side of the forewing, subapical spots in spaces R 3 –M 2 are well-developed, relatively smaller, or reduced to tiny dots; the one in space R 5 may be slightly displaced outwards, while the one in space M 2 may be hardly traceable. The discal band is curved or nearly straight, continuous or interrupted by vein Cu 2 and vein m-cu; it reaches the lower half of space Cu 2 or stops at the upper half of the space; the outer edge of the band is relatively smooth or irregular. One or two spots may be located in the coastal area above the cell spot. The cell spot may be wide or narrow, rectangular or triangular, or broken into two spots. On the ventral side of the hindwing, a series of black spots may be blurred or well defined.

Characters of the male genitalia ( Fig. 4 ) are almost constant among examined specimens. Considering the fact that the male genitalia of Capila lineata lineata have not been described in detail, the following description is provided: Tegumen trapeziform in dorsal view, with anterior edge curved; middle part slightly raised in lateral view. Uncus helmet-shaped, in dorsal view, basal 2/3 gently tapered, distal 1/3 divided into a pair of short and blunt branches, decorated with tiny sawteeth on tip. Gnathos arm-like in lateral view, distal part fused into a well-developed plate in ventral view, with its distal edge concave in middle in posterior view. Saccus as long as tegumen in lateral view, wide and nearly triangular in ventral view. Basal half of valva trapeziform, distal half trifurcate; in lateral view, dorsal branch short and bent downwards, middle branch longer, ventral branch the longest and much thicker, its distal half tapered and bent upwards; in dorsal view, dorsal branch slightly bent outwards, middle branch bent inwards, ventral branch almost straight; distal area of both dorsal and middle branches decorated with spinules. Aedeagus much longer than ventral margin of valva, subzonal sheath inclined to left in dorsal view, shorter than suprazonal sheath; coecum penis slightly bent upwards in lateral view; cornuti densely covered with tiny spines. Juxta bifid into a pair of elongate plates.

In the female, the observed variation in wing pattern is less than that in the male due to a much smaller sample size: the forewing length is 27–29 mm (n = 4); there are four or five small subapical spots on the forewing, of which the last one may be vestigial; the costal area above the cell spot may be blank on the dorsal side of some individuals, but always bears one or two spots on the ventral side. Characters in female genitalia are less variable except for the concavity in the middle of the distal edge of lamella antevaginalis, which may be deep and nearly V-shaped or relatively shallower ( Fig. 5 ).

Status of Capila lineata irregularis and C. neolineata . According to Devyatkin & Monastyrskii (2002: 142), the male of Capila lineata irregularis differs from the nominate subspecies in having five subapical spots instead of four, and the white band interrupted by vein Cu 2, with less regular outer border. These differences fall into the range of intraspecific variation of C. lineata lineata discussed above. A photo of a female C. lineata irregularis from northern Vietnam, identified as C. lineata magna , was exhibited in Ikeda et al. (2001: 59, fig. 20). Judging from the wing patterns, it is undistinguishable from the female of C. lineata lineata . Thus, C. lineata irregularis syn. nov. is considered a junior subjective synonym of the nominate subspecies.

Judging from the original paper of C. neolineata , the male genitalia ( Fan et al. 2003: fig. 2) are exactly the same as those of C. lineata lineata , and characters in the female genitalia ( Fan et al. 2003: fig. 3) fall into the range of individual variation of C. lineata lineata . Thus, the difference between the two taxa is the position of the subapical spot in space R 5 which is shifted outwardly in C. neolineata . In the present study, three males (forewing length 27 mm) and one female (forewing length 30 mm) from the type locality of C. neolineata were examined ( Fig. 5 ), of which the males are consistent with those of C. lineata lineata , while the female is very similar to the paratype of C. neolineata . Both the COI gene sequences and genital characters proved these specimens to be C. lineata lineata . Therefore, C. neolineata syn. nov. is neither a subspecies of C. lineata nor a s eparate species, but a junior subjective synonym of C. lineata lineata .

Discussion. Devyatkin & Monastyrskii (2002: 142) suggested that Capila lineata magna may deserve full species status, due to the reduction of forewing subapical spots, the straighter and narrower forewing discal band, and the middle branch of valva being the longest, compared to C. lineata lineata . Judging from the photos of adults ( Devyatkin & Monastyrskii 1999: pl. XII, fig. 3, 4), wing patterns of both sexes of magna are out of the range of individual variation of C. lineata lineata , but the female genitalia are very similar to those of the latter. Considering the fact that only one male and one female are known for magna, it is better to keep its subspecific rank at present.

Figures

FIGURE 4. Male genitalia of Capila lineata lineata Chou & Gu, 1994 from Wuzhishan, Hainan (Specimen ID C20, Genitalia No. WZS14). A. genital capsule, lateral view. B. ditto, ventral view. C. ring, posterior view. D. ditto, lateral view. E. tegumen & uncus, dorsal view. F. gnathos & uncus, ventral view. G. left valva, outer side. H. ditto, inner side. I. ditto, dorsal view. J. aedeagus, dorsal view. K. ditto, lateral view. L. cornuti, enlarged. N. juxta.

FIGURE 5. Ventral view of female genitalia of Capila lineata lineata Chou & Gu, 1994 from Wuzhishan, Hainan. A1–A3. Specimen ID C24, Genitalia No. WZS33. B. Genitalia No. WZS34.