Drepanosticta brownelli Tinkham, 1938

Phan, Quoc Toan, Yokoi, Naoto, Makbun, Noppadon, Joshi, Shantanu, Subramanian, K. A., Ngo, Quoc Phu & Dow, Rory A., 2021, A review of the Drepanosticta carmichaeli-group, with the description of D. wildermuthi sp. nov. from the Central Highlands of Vietnam (Odonata: Zygoptera: Platystictidae), Zootaxa 5067 (2), pp. 187-210 : 192

Drepanosticta brownelli Tinkham, 1938

( Figures 2a–e )

Drepanosticta brownelli: Tinkham (1938) : original description from Guangdong, South China, Figs 1–2 (appendages in dorsal & dorso-lateral view); Wilson (1997): Guangdong, pp. 59–61, Figs 26–27 (appendages, rearranged from Tinkham 1938), Figs 30–31 (genital ligula in lateral & dorsal view); Wilson & Reels (2003): Guangxi, pp. 271; Dow et al. (2018): p. 274, examined specimens from Guangdong, China; Zhang (2019): brief notes and photographs of both sexes, pp. 1373–1374.

Specimens examined. 2 ♂♂, Nankushan Mountain , Guangdong Province, South China, 28.v.2009, Zhang Haomiao leg. ( KPMNH) ; 1 ♂, Sanyatung Forest Park , Conghua City, Guangdong, China, 15.v.2010, same collector, in coll. Dow.

Notes. This species is only known from Guangdong and Guangxi Provinces in South China ( Tinkham 1938, Wilson 1997, Wilson & Reels 2003, Dow et al. 2018, Zhang 2019). It is closely allied to D. hongkongensis from Hong Kong, which was treated as D. brownelli by Asahina (1987). The synthorax is mostly dark in both species and their anal appendages are very similar to each other. In describing D. hongkongensis Wilson (1997) noted differences between the males of the two in size ( D. brownelli larger), the color of the anterior pronotal lobe (white in D. brownelli , entirely dark in D. hongkongensis ), the color of the terminal abdominal segments and the genital ligula (the differences in the genital ligula are reproduced in our key below). Interestingly Tinkham (1938: pp. 17–18) mentions “a dull white cuneiform marking, with the point down, about centrally placed on the metepimeron [presumably referring to the metepisternum in modern terminology]” but Wilson (1997) does not mention this marking. A pale centrally placed marking on the metepisternum is present in the specimens examined in this study, although its size and exact shape are variable (visible but faded in Fig. 2a ) and a white marking in this position is visible in the photograph of male D. brownelli in Zhang (2019: 1373) and this marking is mentioned as a diagnostic character in the text on the following page. We do not know if the pale metepisternum marking was absent in Wilson’s specimens or if he overlooked it or did not consider it diagnostic, but no such marking is present in any specimen of D. hongkongensis seen by us. Of the other characters mentioned by Wilson (1997), the size character holds when D. brownelli is compared with D. hongkongensis specimens from Hong Kong but as noted in Dow et al. (2018) specimens from Vietnam are larger, overlapping with D. brownelli . Similarly (and again as noted in Dow et al. 2018) the anterior pronotal lobe of specimens of D. hongkongensis from Ba Vi National Park in Vietnam have large yellow marks laterally on the anterior pronotal lobe, so this character is not generally diagnostic either. The other characters listed by Wilson (1997) do appear to hold generally (although the genital ligula has not been examined for variation in multiple specimens), in particular the pale dorsal coloration of the terminal abdominal segments is always paler than those of D. hongkongensis , although slightly contrary to one comment in Wilson’s paper this color is very pale greyish blue in the male from Sanyatung Forest Park, even viewed under strong light. It is worth remarking here that Asahina’s (1987: Fig. 39) illustration (reproduced as Fig. 17 in Wilson 2017) of D. hongkongensis shows two pale marks low on the metepimeron, but these markings are not present on most D. hongkongensis material examined by us and do not provide a diagnostic character. Although Wilson (1997) provided a brief description of the female of D. brownelli he did not provide any illustrations; unfortunately no female specimen of D. brownelli was available for our study.

Distribution. China (Guangdong and Guangxi Provinces) ( Fig. 13 ).

Figures

FIGURE 1. Drepanosticta annandalei ♂ [a, c, e, g, h, i] & ♀ [b, d, f, j], Bamboo Teri,Andaman Island, India (NZC). (a, b), head & thorax, lateral view; (c), head, dorsal view; (d), synthorax, dorsal view; (e, f), terminal segments of abdomen, lateral view; (g–i) appendages in lateral, dorsal and ventral view; (j), pterostigma, ♀.

FIGURE 2. Drepanosticta brownelli ♂, Nankushan Mountain, China (KPMNH). (a), head and thorax, lateral view; (b), prot- horax, lateral view; (c–e), appendages in oblique dorsal, lateral and ventral view.

FIGURE 13. Distribution map of Drepanosticta carmichaeli group. D. vietnamica (yellow circle); D. annandalei (red circle); D. brownelli (white circle); D. carmichaeli (red square); D. emtrai (blue square); D. hongkongensis (pink square); D. jurzitzai (red triangle); D. wildermuthi sp. nov. (yellow triangle); D. sumatrana (pink triangle); D. tenella (red diamond).