The genus Asiagomphus in Vietnam, with descriptions of three new species, and first descriptions of the male of Asiagomphus auricolor (Fraser, 1926) and of the female of Asiagomphus reinhardti Kosterin & Yokoi, 2016 (Odonata: Gomphidae) Author Kompier, Tom text Zootaxa 2018 2018-08-28 4462 3 301 330 journal article 29397 10.11646/zootaxa.4462.3.1 ee3428d1-9e3b-495d-99a5-e61ea679b5e9 1175-5326 1441611 75D121A7-F718-4F69-9E33-E82AB371403A Asiagomphus monticola sp. nov. ( Figs. 4e–f , 5a , 6a , 7a , 8b , 9d , 11a–b ) Material examined: Holotype ♂ , Xuan Son NP , Phu Tho Prov., (appr. 21.163 N , 104.896 E ), 31-V-2014 , TK leg. Paratypes . 1 ♂ , same date, location and collector as holotype ; 1 ♂ , Yen Bai Prov., 1-VI-2014 , TK leg. Additional records based on field observations by TK : 1 ♂ , Xuan Son NP , Phu Tho Prov., 31-V-2014 ; 2 ♂♂ , Xuan Son NP , Phu Tho Prov., 8-VI-2014 . Etymology . The specific name monticola , a noun in apposition, can be translated as “a mountain inhabitant” and refers to the relatively high-altitude habitat of the species compared to its similar-looking relative, Asiagomphus superciliaris . Description of holotype ( Figs. 4e–f , 5a , 6a , 7a , 8b , 9d , 11a ) Head . Labium dark brown, lateral lobes somewhat paler. Labrum black. Anteclypeus blackish brown, somewhat paler in the middle. Postclypeus black. Base of mandibles pale yellow. Postfrons with broad yellow stripe, extending downward to cover the dorsal margin of the otherwise black antefrons. Posterior edge of postfrons black. Cranium black, lateral ocelli with a raised ridge posteriorly with some sparse hairs ( Fig. 9d ). Occiput black, smooth but slightly raised centrally, occipital ridge with long black hairs. Antennae black, but top of first segment pale. Thorax . Prothorax with anterior lobe yellow but black laterally, and median lobe with small yellow central spot and pair of small lateral spots. Synthorax black with yellow markings as follows: Mesepisternum with broad dorsal stripe, straight, merging with collar stripe to form two inverted “7” shapes, and distinct antehumeral spot. Blackish brown mesepimeron with straight broad lateral stripe. Mesokatepisternum blackish brown with yellow spot. Metepisternum blackish brown with distinct yellow spot at postero-dorsal corner and yellow area behind spiracle, extending towards venter. Metakatepisternum dark brown with posterior half yellow. Metepimeron almost completely pale yellow, but black stripe over metapleural suture. Coxae blackish brown and legs all black. Abdomen . Black with yellow markings as follows: S1 with ventral half yellow and center of dorsum yellow; dorso-laterally covered in long black hairs; S2 ventral half to just above auricle yellow and with yellow central line dorsally, posterior margin black; S3 with antero-dorsal half-ring, dorsally somewhat extended to form short longitudinal line, almost extending to ventral margin; S4–5 with short antero-dorsal half-ring; S6–7 with short antero-dorsal half-ring, broken by black dorsal carina; S9 with large yellow marking on posterior half, its anterior margin irregular. S7–9 markedly widened. Accessory genitalia ( Figs. 4e–f ). Anterior hamulus dark reddish brown, about 4x longer than wide, central third somewhat expanded posteriorly, then smoothly constricted towards apex, which is hollowed out, the open side rather wide and directed inward and backward at apex, with tiny teeth at apical margin, and with hairs extending from broader base internally. Posterior hamulus black, robust, in lateral view 2.5x length of visible part of anterior hamulus, smooth, lateral surface concave near base, its anterior margin becoming a ridge over lateral side at midpoint, apex curved smoothly anteriorly to form hook, and anterior margin angular, with small teeth at mid-point ( Fig. 4e ). Vesica spermalis . Flagellum extending well beyond somewhat slender median process of apical segment, tip of flagellum short, directed downward at 45 degree angle. Wings. Hyaline with black veins, with brownish tinge. Anal triangle 3-celled, cubito-anal space with one crossvein, all triangles uncrossed, nodal index 14–17:16– 14 in FW, 14–13: 11–13 in HW. Pt brown, 3.5 mm , covering 5 cells in FW and 5 in HW. Anal appendages ( Figs. 5a , 6a , 7a , 8b ). Blackish brown. Cerci simple, unbranched, widely diverging in dorsal view and apically tapering to a posteriorly directed point ( Fig. 5a ), in lateral view slightly curved downward, apically inflicted upwards to form sharp, slightly raised, tip, in length cerci approximately 1.3x length of S10, as long as epiproct ( Fig. 6a ). Epiproct deeply triangularly incised, not v-shaped, but more rounded, in dorsal view branches diverging as much as cerci and triangular ( Fig. 5a ), rather flat, tapering to a slightly inward arched blunt tip, at middle slightly bulging and with rounded depression supapically ( Fig. 8b ). In lateral view, ventral margin first slanting downward, then at two-fifths from base rising again. Dorsal margin straight at base, then shallowly concave. Apical three-fifths not noticeably thinning ( Fig. 6a ), apex with a blunt point, hooked inward and upward to form small dorsal tooth. Measurements (in mm). Total length (incl. appendages) 62, HW 38. Variation in paratype males. In the second Xuan Son male, lateral lobes of labium pale yellow. Dorsal yellow spot on metepisternum somewhat smaller, but distinct. Superior appendages slightly extending beyond epiproct. Nodal index 13–15:17– 13 in FW, 13–10: 11–12 in HW. Male from Yen Bai ( Fig. 11b ) with lateral lobes of labium largely pale yellow, metepisternum with complete yellow stripe, S1 yellow but for dorso-lateral hairy area, only half-ring of S7 broken dorsally, yellow mark on S9 covering only apical third. Subapical depression of epiproct branches elongated. Nodal index 16–19:20– 16 in FW, 15–14: 14–15 in HW. Measurements (in mm). Total length (incl. appendages) 62–66, HW 39–41. Female. Unknown. FIGURE 9. Vertex in antero-dorsal view. [a–d] male, [e–f] female, (a) Asiagomphus superciliaris holotype; (b) A. superciliaris paratype Huu Lien NR, 24-V-2014; (c) A. superciliaris paratype Bac Kan Prov., 5-IV-2015; (d) A. monticola holotype; (e) A. auricolor female used for description; (f) A. reinhardti female used for description. Differential diagnosis. Asiagomphus monticola sp. nov. is very dark species, easily separable from other species occurring in Vietnam by a combination of aspects of coloration and structural characteristics, apart from the similarly dark A. superciliaris and A. xanthenatus . The paratype from Yen Bai Province and the types from Xuan Son NP, Phu Tho Prov., differ somewhat in coloration, especially regarding the extent of yellow on the metepisternum, complicating identification. It differs from A. superciliaris by much less dense hairs on face and body, particularly on the ridge behind the lateral ocelli (compare Fig. 9d with Figs. 9a–c ), by the presence of an antehumeral spot, by at least some distinct yellow markings on the metepisternum (compare Figs. 11a–b with Figs. 11c–e ), by the apex of the posterior hamulus not being curled, but flat and directed more anteriorly than inward (compare Fig. 4e–f with Fig. 4g –h ), and by the differently shaped anterior hamulus, which is not as suddenly constricted below the apex and directed more inwards, not turned outward, and has teeth on the lateral margin of the apex (smooth in A. superciliaris , compare Fig. 4e with Fig. 4g ). Asiagomphus xanthenatus differs for instance by the shape of the epiproct branches without a median ridge and supapical bowl, and by the slender anterior hamulus in anterior view, with more narrow apex directed posteriorly. The even darker A. acco lacks yellow halfrings or spots on S3–6, and has a ventral tooth on the cerci, next to other differences. All Chinese, Korean, and Japanese species have a distinct complete antehumeral stripe or, in case they only have an antehumeral spot, have different thorax patterns, and generally have lengthwise dorsal stripes on the abdomen. Asiagomphus reinhardti is easily identified by the protrusion of the posterior margin of S10 and different cerci ( Fig. 6g ) in addition to clearly different markings. The western species A. nilgiricus and A. personatus have longitudinal markings on the abdomen ( Fraser 1925 ) and A. odoneli has differently marked S8–9. These species also have different thorax pattern and structural differences. Asiagomphus auricolor has U-shaped epiproct incision, posterior margin between its branches straight ( Fig. 5a ), and has a slender apex of the, in anterior view slender, anterior hamulus, with distinct teeth along its apical posterior margin, directed posteriorly ( Fig. 4a–b ). Habitat and ecology. Asiagomphus monticola was found in semi-open terrain, at alt. 1,000–1,100 m , near tracts of good forest, by small streams on cleared land.