Bayadera hatvan sp. nov. from northern Vietnam (Odonata: Euphaeidae)

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1 TOMBO, 57: May 10, 2015 Article Bayadera hatvan sp. nov. from northern Vietnam (Odonata: Euphaeidae) Matti Hämäläinen 1) & Tom Kompier 2) 1) Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA, Leiden, the Netherlands 2) Schoutenstraat 69, 2596 SK, Den Haag, the Netherlands Received Jan. 07/ Revised and accepted Mar. 15 Abstract: A new euphaeid damselfly species, Bayadera hatvan sp. nov. (holotype male from Vietnam, Yen Bai province) is described and illustrated for both sexes. A comparison with the superficially similar B. indica (Selys, 1853) is provided. This brings the total number of species known in the genus to 17. Key words: Odonata, Euphaeidae, Bayadera, Bayadera hatvan, new species, Vietnam, Bayadera indica. Introduction The euphaeid damselfly genus Bayadera Selys, 1853 presently includes 16 described species, all inhabitants of montane streams in the Oriental region. The genus is most speciose in southern China. The last overview of the genus was published by Davies & Yang (1996) and a brief discussion of further advances in the taxonomic knowledge of the genus after 1996 was given by Hämäläinen (2013). This paper describes a new Bayadera species from northern Vietnam on the basis of several specimens of both sexes (Figs.1a & 1b), recently collected in locations in three provinces less than 100 km south of the Chinese border. This brings the total number of known species in the genus to 17. Superficially, the new species resembles B. indica (Selys, 1853), a species known from northern and north eastern India, Nepal, Sikkim and Bangladesh. Bayadera hatvan sp. nov. (Figs. 1a, 1b, 3, 4a, 4c, 4e, 5a, 5b) Type series. Holotype, Vietnam, Yen Bai province, stream crossing the road QL 32 at N, E, altitude 800 m, 3 VII 2014, Tom Kompier leg.; Paratypes: 1, same collecting data as in holotype; 1, same collecting data as in holotype, but date 11 V 2014; 1, same collecting data as in holotype, but date 4 VII 2014; 1, Vietnam, Yen Bai province, at N, E, alt m, 1 VI 2014, Tom Kompier leg.; 1, Vietnam, Yen Bai province, Mu Cang Chai district, Tu Le community, 19 V 2014, Phan Quoc Toan leg.; 1, Vietnam, Ha Giang province, at N, E, alt. 660 m, 1 VII 2014, Tom Kompier leg.; 1, Cao Bang province, Nguyen Binh, Pia Oac, 6 VI 2009, Phan Quoc Toan leg.; 2, Cao Bang province, Thanh Cong, 3 I 2009, Phan Quoc Toan leg. Type depository. Holotype is deposited at Naturalis Biodiversity Center (RMNH), Leiden, the Netherlands. Etymology. The specific epithet hatvan (a noun in apposition) is based to the Vietnamese term hát văn, a contraction of hát chầu văn. It refers to a traditional folk art form in northern Vietnam which combines singing and dancing. This is in accord with the meaning of the genus name Bayadera: bayadére is the French version of the Portuguese word bailadeira, which refers to a Hindu dancing girl in Indian temples. Selys Longchamps (1853) introduced the genusgroup name Bayadera for his Indian species Epallage indica. Description of male holotype. A fully mature male specimen. Head. Labium black, mentum and middle lobe pruinosed, lateral lobes yellow, tips black. Anterior and dorsal part of head with extensive pale blue markings (cf. Fig. 3). Labrum largely blue, with borders black and with a deep black rounded incision medially. Base and mandibles and genae blue, blue colour extending upwards almost to the level of the lateral ocelli. Clypeus, frons, vertex and occiput matt black. Antennae black. In life eyes dark brown above, steel bluish below (cf. Fig. 1a). Rear of eyes slightly pruinosed. Thorax. Prothorax black with yellow markings on the anterior lobe, sides of middle lobe broadly yellow; posterior

2 Matti Hämäläinen & Tom Kompier lobe raised to form an oblique upright flap. Synthorax matt black with conspicuous yellow stripes as in Fig. 1a. Metepisternum and metepimeron slightly pruinosed at the anterior corners below stigma. Underside of synthorax largely pale with two horizontal black stripes in the posterior half. Coxae black in middle, yellowish and pruinosed on sides. Legs otherwise black, but femora with yellow streak on flexor surface, the yellow stripe narrowing towards apex. Wings. Hyaline with apex darkened, the dark colour starting at level of half way of pterostigma (cf. Fig. 1a). Wing bases with pale brownish tint at upper part of wings, extending to nodus. Pterostigma brown, narrow and long, covering underlying 9-10 cells. Quadrangle entire. Cubital space with one crossvein. Antenodals number in fore wing, 1517 in hind wing; postnodals correspondingly and Abdomen. Black, S1 (segment 1) with yellow lateral spots, which cover most of side of segment. S2 with yellow lateral stripe, broadest at apex. S3 and S4 with narrow yellow lateral stripe, broadest at base, not reaching apex of segment; stripe on S4 very narrow and shorter. A vestige of yellow spot at base of S5 and S6. Very narrow stripe along the mid-dorsal ridge on S2 to S8. Underside of abdomen all black. Anal appendages. Black, cerci long, almost three times longer than S10, paraprocts broad at base, narrowing rapidly to form acute apex; divaricate, about half of length of cerci (Fig. 4a). In dorsal view apex of cerci broadened and depressed to form a triangular plate, which is hollowed out below. In dorsal view the apex of cerci turning towards each other (Fig. 4c). Cerci with two interior spines. A robust ventral spine near base directed obliquely apicad. A much smaller and blunter spine further apicad, directed obliquely basad (Figs. 4c & 4e), these spines not visible in lateral view (Fig. 4a). Penis. Of the typical shape for the genus (cf. Kennedy 1920, plate 1, figs. 30 & 31). Measurements (mm). Forewing 31.5, hind wing 30, abdomen (incl. appendages) 35. Fig. 2. Bayadera indica. A pair in tandem photographed in nature at Pokhara, Nepal on 11 IX Photo by Karen Connif. Fig. 1. Bayadera hatvan sp. nov. a. male, b. female, photographed in nature at the type locality on 11 V Photos by Tom Kompier. Fig. 3. Frontal view of head of living paratype male (collected on 1 VI 2014) of Bayadera hatvan sp. nov. 16

3 Bayadera hatvan sp. nov. from northern Vietnam Fig. 4. Male anal appendages of Bayadera hatvan sp. nov. holotype (a, c, e) and B. indica (b, d, f), specimen from Nepal (Hali Lekh, 23 VI 1986, ex coll. G. S. Vick); a, b. lateral view, c, d. dorsal view and e, f. oblique dorsal view. 17

4 Matti Hämäläinen & Tom Kompier Female. Head. Colour pattern resembles that in male holotype, but markings paler bluish in life, turning yellowish in dead specimens. In life the eyes above slighly paler brown than in male (Fig. 1b). Thorax. Prothorax black with similar yellow markings as in male, but markings somewhat more extensive. Posterior lobe with two distinct divergent horns laterally, raised obliquely upwards, sharp at apex (Figs. 5a & 5b). Colour pattern of synthorax similar as in male, stripes slightly broader (Fig. 1b). Legs as in male. Wings. Hyaline without any distinct darkening at wing tip. An obscure brownish suffusion at upper part of the wings extending to the level of nodus (Fig. 1b). Venation quite similar as in male. Abdomen. Proportionally shorter and more robust than in male. Colour pattern resembling that of male; in some specimens narrow lateral stripes also on S5 S7, and a small lateral spot apically on S8, obviously age related character. S9 with a yellow lateral spot in apical part in all specimens. Anal appendages black. Tip of vulvar scale pale; ovipositor brown. Measurements (mm). Hind wing 32 33, abdomen (incl. appendages) Variability in paratype males. Paratypes are somewhat larger in size than holotype. There is some variation in the extend of pale markings on side of abdomen; in some specimen pale stripes present only in S2 S3, in others on S2 S4 or S2-S5, obviously partly an age dependant character. Small variation in venational details; in one specimen one fore wing with two cross veins in cubital space; quadrangle entire in all wings in all paratypes. Measurements (mm). Hind wing , abdomen (incl. appendages) Distinguishing characters. Superficially B. hatvan sp. nov. resembles B. indica in the wing colour pattern, in the general shape of male anal appendages and in the structure of the posterior lobe of prothorax in female. However, there are clear differences in the details of male anal appendages, which can be seen by comparing Figs. 4a 4f. In hatvan the cerci are proportionally longer and narrower and not as distinctly turned downwards apicad as in indica. In hatvan the apical widening of cerci, seen from the dorsal view, is not as prominent as in indica. In hatvan the basal ventral spine of cerci is not as robust as in indica, and unlike in indica, it is not visible in lateral view. In hatvan male the pale markings on thorax and abdomen are orange yellow (Fig. 1a), but greenish yellow in indica male (Fig. 2). In indica male the wings of are not as distinctly suffused at base than in hatvan. The females of hatvan and indica do not have clear structural differences. Both species have distinct upright horns on the posterior lobe of prothorax (Figs. 5a & 5b). In the few studied indica specimens, from both India and Nepal, the length of the horns is somewhat variable, in some specimens they are shorter and in some specimens slightly longer than those in hatvan. In hatvan there are obscurely dark suffused stria at wing bases extending to nodus (Fig. 1b), in indica the wing bases are clear (Fig. 2) or have pale saffron colour. B. indica is larger in size than B. hatvan. In indica the length of male hind wing is usually mm, in the known specimens of hatvan correspondingly mm. The length of abdomen is mm and mm, correspondingly. Notes on habitat and behaviour. All B. hatvan records were made on moderately fast to fast flowing, larger (>10 m wide) streams in mountainous surroundings. Males would either perch on large rocks and boulders in the stream or on the tips of snags overhanging the water at a height of one to several metres. Females were observed mixed in with males perching on snags, or on nearby bush. Although the streams were easily accessible and open, they ran through mountainous hills with secondary or degraded forest. During cloudy conditions males retreated. Discussion From the females of the known species of Bayadera, only indica and hatvan have horn-like structures in the hind lobe of female prothorax. This, and the similarity of male anal appendages suggest that these two species are closely related. Davies & Yang (1996) recorded one male specimen of Bayadera, identified as B. indica, from Jiangcheng County in Yunnan, collected on 27 July This is the only published record of this species from China. Based on the three figures of anal appendages of this specimen presented by Davies & Yang (1996, Figs ), we presume that this specimen is B. hatvan, rather than B. indica. Study of this specimen, or discovery of further specimens in the

5 Bayadera hatvan sp. nov. from northern Vietnam Fig. 5. Female prothorax of Bayadera hatvan sp. nov.: a. lateral view, b. dorsal view.. same area in Yunnan, is needed to confirm this supposition. Acknowledgements Dr Rory Dow took the photographs of the structures of B. hatvan and B. indica. Mrs Karen Connif sent us her fine photo of B. indica pair in tandem. Mr Phan Quoc Toan, Mr Do Manh Cuong, Dr Haomiao Zhang and Mr Graham S. Vick provided specimens and/or information. Dr Albert G. Orr made useful comments on the manuscript and improved the English expression. Dr Sami Karjalainen gave technical help in arranging the layout of illustrations. We are grateful to all of them. References Davies, D. A. L. & B. Yang, New species of Bayadera Selys and Schmidtiphaea Asahina from China (Odonata, Euphaeidae). Tijdschrift voor Entomologie, 139: Hämäläinen, M., Description of Bayadera kinnara sp. nov. from Burma, with taxonomic notes on its congeners (Odonata: Euphaeidae). Tombo, 55: Kennedy, C. H., The phylogeny of the zygopterous dragonflies as based on the evidence of the penes. The Ohio Journal of Science, 21: 19 29, pls. 1 3 excl. Selys Longchamps, E. de, Synopsis des Caloptérygines. Bulletins de l Académie Royale des sciences, des lettres et des beaux-arts de Belgique, 20 (Annexe): 摘 要 Matti Hämäläinen & Tom Kompier 北ベトナムから得られた新種 Bayadera hatvan トンボ目 ミナミ カワトンボ科 ミナミカワトンボ科の新種 Bayadera hatvan 完模式標本 ベトナム Yen Bai 県 の雌雄を記 載した 形態的に類似した B. indica との比較を行った 本記載により本属種は 17 種を数えることとなる 19