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| Zhangixalus franki
Ninh, Nguyen, Orlov, Nguyen & Ziegler, 2020
DOI: 10.5852/ejt.2020.688
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Abstract
We describe a new species of the genus Zhangixalus Li, Jiang, Ren & Jiang, 2019 from Ha Giang Province, Vietnam based on morphological and molecular data. In the molecular phylogenetic analyses, the new species is nested in the Zhangixalus duboisi (Ohler, Marquis, Swan & Grosjean, 2000) group, where it is sister to Z. duboisi with a genetic distance of 2.51%. The new species, Zhangixalus franki sp. nov., differs from its congeners by a combination of the following morphological characters: size large, SVL 77.9–85.8 mm in males; finger webbing formula I1-1II0-1III½-0IV; dorsal surface of head and body green with dark brown spots; ventral surface grey or dark grey, white stripe along edge of jaw, insertion of limbs, and along lateral ridges of fore and hind limbs and flank, separating upper green part from lower grey part. The new species occurs in evergreen montane tropical forests at an elevation of ca 1300 m a.s.l. The new discovery brings the total number of known species in the genus Zhangixalus to 38 and the species number reported from Vietnam to nine.
Keywords: New species; Zhangixalus franki sp. nov.; molecular phylogeny; taxonomy; Vietnam
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| Fig. 2. Zhangixalus franki sp. nov. from Quan Ba District, Ha Giang Province, northern Vietnam.A–B. Dorsal and lateral views. C. Drawing of ventral view of left hand and right foot of the adult male holotype (VNMN 011682). |
Class Amphibia Gray, 1825
Order Anura Fischer von Waldheim, 1813
Family Rhacophoridae Hoffman, 1932
Genus Zhangixalus Li, Jiang, Ren & Jiang, 2019
Zhangixalus franki sp. nov.
Diagnosis The new species can be assigned to the genus Zhangixalus based on the following morphological characters: snout pointed; presence of intercalary cartilage between terminal and penultimate phalanges of digits, distal end of terminal phalanx in Y-shape; tips of digits expanded into large disks, bearing circum-marginal grooves; fingers webbed; presence of supra-cloacal dermal ridge; and pupil horizontal (Jiang et al. 2019). In addition, the new species is unambiguously nested in the genus Zhangixalus by molecular phylogenetic evidence. It is closely related to Z. duboisi and Z. omeimontis and nested in the same clade with Zhangixalus dugritei (David, 1872),
the type species of this genus. The new species is distinguished from its congeners by a combination of the following morphological characters: 1) size large (SVL 77.9–85.8 mm for the males); 2) head slightly wider than long; 3) snout pointed; 4) dorsal skin smooth; 5) finger webbing formula I1-1II0-1III½-0IV; 6) dorsal surface of head and body green with dark brown spots; 7) lower jaw region greyish, throat, chest and belly white; 8) white stripe along edge of jaw, insertion of limbs, and along lateral ridges of fore limbs, hind limbs and flank, separating upper green part from lower grey part.
Etymology We name this new species in honor of Dr Frank Mutschmann, late amphibian veterinarian and conservationist from Berlin, Germany, in recognition of his support of our amphibian research and conservation projects in Vietnam. As common names we suggest Frank’s Tree Frog (English), Ếch cây frank (Vietnamese) and Franks Ruderfrosch (German).
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| Fig. 3. Map showing the type locality of Zhangixalus franki sp. nov. (●) in Quan Ba District, Ha Giang Province, northern Vietnam and distribution of Z. burmanus (Andersson, 1939) (◊), Z. duboisi (Ohler, Marquis, Swan & Grosjean, 2000) (▲) and Z. omeimontis (Stejneger, 1924) (☆ orange star). |
Distribution Zhangixalus franki sp. nov. is currently known only from the type locality in Ha Giang Province, northern Vietnam (Fig. 3). The species was recorded at elevations between 1320 and 1360 m a.s.l.
Natural history Specimens of the new species were collected from 19:00 to 24:00 on trees, close to small ponds in undisturbed evergreen forest (Fig. 4). Other tree frogs that were found at the same site were Polypedates sp. (of the P. leucomystax species complex), Z. duboisi and Kurixalus sp. Females, larval stages and eggs of the new species are unknown.
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| Fig. 4. Habitat of Zhangixalus franki sp. nov. at the type locality in Quan Ba District, Ha Giang Province, Vietnam. |
Hoa Thi Ninh, Tao Thien Nguyen, Nikolai Orlov, Truong Quang Nguyen and Thomas Ziegler. 2020. A New Species of the Genus Zhangixalus (Amphibia: Rhacophoridae) from Vietnam. European Journal of Taxonomy. 688; 1-18. DOI: 10.5852/ejt.2020.688
