Halpe paupera Devyatkin 2002

Halpe paupera Devyatkin, 2002

Halpe paupera Devyatkin, 2002: 129, type locality: central Vietnam, Thanh Hoa Province, Xuan Mu district, loc. Xuan Lien; Lo 2005: 122, 123 (description, photos of adults and larva); Chiba 2008: 342, 344 (check list); Devyatkin 2008: 293 (comparison with H. babensis); Wang & Tang 2012: 58 (distribution), pl. 109, figs. 13, 14 (photos of male); Yuan et al. 2015: 398 (description, distribution); Xue et al. 2016: 321 (distribution); Wu & Hsu 2017: 1368 (description, biology, distribution), 1370 (photos of both sexes); Wang et al. 2020: 333 (description, distribution, photos of adult in nature).

Haple paupera paupera: Maruyama 2010: 17, fig. 2 (photos of male); Nakamura & Wakahara 2012: 58 (check list), pl. 25, fig. He-112 (photos of both sexes); Monastyrskii & Devyatkin 2016: 77 (check list).

Haple paupera walthewi Devyatkin, 2002: 131, type locality: Hong Kong; Yuan et al. 2015: 399 (description, distribution); Xue et al. 2016: 321 (discussion on the taxonomic status of H. paupera walthewi). syn. nov.

Although there are only two males and two females in the type series of Haple paupera, some variation in the wing patterns of both sexes can be noticed, as described by Devyatkin (2002). By comparing more specimens from different localities, the variability of the species in both external and genital characters are discussed as follows.

Intraspecific variability in male. According to the original description (Devyatkin 2002: 129), the upper cell spot on the forewing is well-developed and elongate, while the lower one is much smaller. Judging from the examined specimens in the present paper and figures in literature, the upper cell spot may be elongate (Fig. 1: C, F; Maruyama 2010: fig. 2a, 2b), or equal in size to the spot in space R 5 (Fig. 1: A, B, E); the lower cell spot may be more developed than the upper one (Fig. 1: A), or smaller than the latter (Fig. 1: B, C, E; Maruyama 2010: fig. 2a, 2b), or absent on the dorsal side of forewing (Fig. 1: F).

The male genitalia show an impressive variability: the tip of uncus may be rounded (Fig. 2: D; Fig. 5: C; Maruyama 2010: fig. 2c) or angled (Fig. 3: D; Fig. 4: A), and the cleft may be shallow and narrow (Fig. 2: D; Fig. 3: D), shallow and wide (Fig. 4: A) or relatively deep (Fig. 5: C; Devyatkin 2002: fig. 3A; Maruyama 2010: fig. 2c); the end of the lateral process of uncus is hooked (Fig. 2: A; Fig. 3: A; Fig. 5: B; Maruyama 2010: fig. 2f) or blunt ventrally (Fig. 4: D); the costal lobe (“footstalk” by Evans 1949) at the base of valva is short and pointed (Fig. 2: F, G, H; Fig. 5: C, D; Devyatkin 2002: fig. 3B; Maruyama 2010: fig. 2c, 2e, 2f), or missing (Fig. 3: F, G, H; Fig. 4: A, I, J, K); the proximal branch at distal valva is longer than or equal to the distal one (Fig. 2: E, F, G; Fig. 3: E, F, G; Fig. 5: B, C; Devyatkin 2002: fig. 3B; Maruyama 2010: fig. 2e), or much shorter than the latter (Fig. 4: C, I, J, K); the distal branch is bent upwards (Fig. 2: E; Fig. 3: E; Fig. 4: C; Devyatkin 2002: fig. 3B; Maruyama 2010: fig. 2d) or semi-erect (Fig. 5: A), it may be elongated (Fig. 2: E; Fig. 5: B; Devyatkin 2002: fig. 3B; Maruyama 2010: fig. 2d, 2e) or relatively shorter but much more expanded (Fig. 3: E; Fig. 4: C). Characters of other parts of the male genitalia, such as gnathos, aedeagus and juxta, are identical in the examined specimens and the description by Devyatkin (2002).

Intraspecific variability in female. Devyatkin (2002) described Haple paupera walthewi as a new subspecies based upon one female specimen from Hong Kong, because the lower cell spot on the forewing of the specimen is well developed (visible as a small dot on both sides of forewing in the nominate subspecies), and there are two small but sharp (especially on the ventral side) spots present in space Cu 2, directed to the middle of vein 2A (no trace of such spots in the nominate paupera) (Devyatkin 2002: 129, 131, pl. IV, fig. 5–8). Although Devyatkin (2002) did not provide photos of female H. paupera paupera, Nakamura & Wakahara (2012: pl. 25, fig. He-112) illustrated a female specimen from central Laos, of which the wing patterns agree with Devyatkin (2002) ’s description of the nominate subspecies. However, judging from the female specimens from Hong Kong examined in the present study, the lower cell spot on the forewing may be developed (Fig. 6: B) or reduced and much smaller than the upper one (Fig. 6: A, C, D); in space Cu 2, there is a dot adjacent to the middle of vein 2A, and it is well defined on the dorsal side of the wing but vestigial on the ventral side (Fig. 6: A, B); the spot, however, is absent on the dorsal side or both sides of forewing in some individuals (Fig. 6: C, D). Moreover, a female specimen from Guizhou bears relatively developed lower cell spot but no spot in space Cu 2 (Fig. 1: D). Therefore, the population from Hong Kong cannot be separated from the nominate subspecies by wing patterns of the female, and the holotype of walthewi represents an aberration, as pointed out by Devyatkin (2002). Thus, walthewi is treated as a synonym of paupera herein.

Distribution and bionomics. In the present study, three new localities are found for Halpe paupera (Fig. 7), and, therefore, its distribution range is significantly extended northward. At Simianshan in Chongqing, the northernmost locality (Fig. 7: A), the species was found at an altitude of 1,500 meters. At Fanjingshan in Guizhou (Fig. 7: B), it was observed flying around the canopy at an altitude of 1,000 –1,300 meters and sometimes perching on leaves in a typical posture of the subfamily Hesperiinae (Fig. 8). Near the border with Vietnam (Fig. 7: C), it is a very rare species and was discovered at an altitude of 160 meters, not far from villages. In the northern part of its distribution range (Fig. 7: A, B), the adult flies from mid-July to mid-August, while in southern Guangxi (Fig. 7: C) and Hainan it was found in May. The population in Hong Kong is bivoltine with adult on the wing in May and October and diapause as early instar larva in winter. Larvae in Hong Kong (Fig. 9) are known to feed on Indocalamus herklotsii, a bamboo species of Poaceae family.

Conclusion. Halpe paupera exhibits remarkable morphological variability in both wing patterns and male genitalia.The subspecies walthewi cannot be distinguished from the nominate subspecies by any stable morphological characters, and therefore should be considered a synonym of the latter. The north boundary of this species reaches southwestern Chongqing of China. The taxon was observed at the altitude of 160–1500 meters within its distribution range.

Discussion. A very similar species, Halpe babensis Devyatkin, 2008, was described from northern Vietnam based upon one male specimen. Judging from the original description (Devyatkin 2008: 293, fig. 3; pl. 19A: fig. 5, 6), characters of the wing pattern and male genitalia of this species fall into the intraspecific variation of H. paupera as discussed above. Hence the taxonomic status of H. babensis requires further study.