Research Article |
Corresponding author: Bin Wang ( wangbin@cib.ac.cn ) Academic editor: Annemarie Ohler
© 2020 Ning Xu, Shi-Ze Li, Jing Liu, Gang Wei, Bin Wang.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Xu N, Li S-Z, Liu J, Wei G, Wang B (2020) A new species of the horned toad Megophrys Kuhl & Van Hasselt, 1822 (Anura, Megophryidae) from southwest China. ZooKeys 943: 119-144. https://doi.org/10.3897/zookeys.943.50343
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A new species of the genus Megophrys is described from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent clade sister to M. minor and M. jiangi. The new species could be distinguished from its congeners by a combination of the following characters: body size moderate (SVL 43.4–44.1 mm in males, and 44.8–49.8 mm in females; vomerine teeth absent; tongue not notched behind; a small horn-like tubercle at the edge of each upper eyelid; tympanum distinctly visible, rounded; two metacarpal tubercles on palm; relative finger lengths II < I < V < III; toes without webbing; heels overlapping when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level between tympanum and eye when leg stretched forward; in breeding males, an internal single subgular vocal sac in male, and the nuptial pads with black spines on dorsal surface of bases of the first two fingers.
Taxonomy, molecular phylogenetic analysis, morphology
The Asian horned toad Megophrys Kuhl & Van Hasselt, 1822 (Anura: Megophryidae Bonaparte, 1850) is widely distributed in eastern and central China, throughout southeastern Asia, and extending to the islands of the Sunda Shelf and the Philippines (
The large genus Megophrys currently contains 98 species, of which 41 species were described in the last decade (
During field surveys in the Chishui National Nature Reserve, Chishui City, Guizhou Province, China, we collected a series of Megophrys specimens. Our molecular phylogenetic analyses and morphological comparisons support it as an undescribed species, and it is described herein as a new species.
Three adult males and five adult females of the undescribed species were collected in Chishui National Nature Reserve, Chishui City, Guizhou Province, China (Suppl. material
Six specimens of the undescribed species were included in the molecular analyses (Suppl. material
For molecular analyses, the available sequence data for congeners of Megophrys were downloaded from GenBank (Suppl. material
Measurements of the adult specimens of Megophrys chishuiensis sp. nov. Units are given in mm. See abbreviations for the morphological characters in Materials and methods section.
Male (N = 3) | Female (N = 5) | |||
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Range | Mean ± SD | Range | Mean ± SD | |
SVL | 43.4–44.1 | 43.6 ± 0.4 | 44.8–49.8 | 47.8 ± 2.0 |
HDL | 11.4–11.9 | 11. 7 ± 0.3 | 11.2–12.7 | 11.7 ± 0.6 |
HDW | 13.0–13.9 | 13.5 ± 0.5 | 13.8–15.4 | 14.7 ± 0.6 |
SL | 4.2–5.3 | 4.8 ± 0.6 | 4.3–5.4 | 4.9 ± 0.4 |
IND | 5.0–5.2 | 5.1 ± 0.1 | 4.5–5.8 | 5.1 ± 0.6 |
IOD | 3.1–3.5 | 3.3 ± 0.2 | 3.1–4.3 | 3.5 ± 0.5 |
ED | 4.4–5.0 | 4.7 ± 0.3 | 4.9–5.7 | 5.4 ± 0.3 |
UEW | 4.1–4.9 | 4.4 ± 0.4 | 4.1–5.2 | 4.7 ± 0.4 |
TYD | 2.8–3.5 | 3.2 ± 0.4 | 2.2–3.1 | 2.7 ± 0.3 |
LAL | 18.4–20.0 | 19.0 ± 0.9 | 20.3–22.0 | 21.3 ± 0.7 |
LW | 4.5–4.7 | 4.6 ± 0.1 | 3.2–3.6 | 3.4 ± 0.2 |
HLL | 59.4–65.1 | 63.0 ± 3.1 | 64.2–75.6 | 70.7 ± 4.1 |
THL | 17.2–21.3 | 19.8 ± 2.2 | 20.4–23.8 | 22.1 ± 1.3 |
TL | 18.0–21.7 | 20.1 ± 1.9 | 22.0–24.0 | 23.2 ± 0.8 |
TW | 4.6–5.1 | 4.9 ± 0.3 | 5.0–5.8 | 5.3 ± 0.3 |
TFL | 28.0–30.2 | 28.9 ± 1.2 | 30.1–33.0 | 31.3 ± 1.1 |
FL | 18.5–19.2 | 18.9 ± 2.3 | 18.8–22.1 | 21.0 ± 1.4 |
Phylogenetic relationships were reconstructed based on the mitochondrial DNA data and nuclear DNA data, respectively. Phylogenetic analyses were conducted using maximum likelihood (ML) and Bayesian Inference (BI) methods, implemented in PhyML v. 3.0 (
All adult specimens of the undescribed species were measured. The terminology and methods followed
ED eye diameter (distance from the anterior corner to the posterior corner of the eye);
FL foot length (distance from tarsus to the tip of fourth toe);
HDL head length (distance from the tip of the snout to the articulation of jaw);
HDW maximum head width (greatest width between the left and right articulations of jaw);
HLL hindlimb length (maximum length from the vent to the distal tip of the Toe IV);
IND internasal distance (minimum distance between the inner margins of the external nares);
IOD interorbital distance (minimum distance between the inner edges of the upper eyelids);
LAL length of lower arm and hand (distance from the elbow to the distal end of the Finger IV);
LW lower arm width (maximum width of the lower arm);
SL snout length (distance from the tip of the snout to the anterior corner of the eye);
SVL snout-vent length (distance from the tip of the snout to the posterior edge of the vent);
TFL length of foot and tarsus (distance from the tibiotarsal articulation to the distal end of the Toe IV);
THL thigh length (distance from vent to knee);
TL tibia length (distance from knee to tarsus);
TYD maximal tympanum diameter;
TW maximal tibia width;
UEW upper eyelid width (greatest width of the upper eyelid margins measured perpendicular to the anterior-posterior axis).
We compared morphological characters of the undescribed species with Megophrys congeners. Comparative data were obtained from related species as described in literature (Table
References for morphological characters for congeners of the genus Megophrys.
Species | Literature |
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M. aceras Boulenger, 1903 | Taylor 1962 |
M. acuta Wang, Li & Jin, 2014 |
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M. ancrae Mahony, Teeling & Biju, 2013 |
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M. angka Wu, Suwannapoom, Poyarkov, Chen, Pawangkhanant, Xu, Jin, Murphy & Che, 2019 |
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M. auralensis Ohler, Swan & Daltry, 2002 |
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M. baluensis (Boulenger, 1899) | Boulenger 1899 |
M. baolongensis Ye, Fei & Xie, 2007 |
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M. binchuanensis Ye & Fei, 1995 |
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M. binlingensis Jiang, Fei & Ye, 2009 |
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M. boettgeri (Boulenger, 1899) |
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M. brachykolos Inger & Romer, 1961 |
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M. carinense (Boulenger, 1889) |
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M. caobangensis Nguyen, Pham, Nguyen, Luong & Ziegler, 2020 |
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M. caudoprocta Shen, 1994 |
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M. cheni (Wang & Liu, 2014) |
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M. chuannanensis (Fei, Ye & Huang, 2001) |
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M. damrei Mahony, 2011 |
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M. daweimontis Rao & Yang, 1997 |
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M. dongguanensis Wang & Wang, 2019 | Wang et al. 2019 |
M. dringi Inger, Stuebing & Tan, 1995 |
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M. edwardinae Inger, 1989 |
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M. elfina Poyarkov, Duong, Orlov, Gogoleva, Vassilieva, Nguyen, Nguyen, Nguyen, Che & Mahony, 2017 |
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M. fansipanensis Tapley, Cutajar, Mahony, Nguyen, Dau, Luong, Le, Nguyen, Nguyen, Portway, Luong & Rowley, 2018 |
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M. feae Boulenger, 1887 |
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M. feii Yang, Wang & Wang, 2018 |
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M. flavipunctata Mahony, Kamei, Teeling & Biju, 2018 |
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M. gerti (Ohler, 2003) |
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M. gigantica Liu, Hu & Yang, 1960 |
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M. glandulosa Fei, Ye & Huang, 1990 |
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M. hansi (Ohler, 2003) |
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M. himalayana Mahony, Kamei, Teeling & Biju, 2018 |
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M. hoanglienensis Tapley, Cutajar, Mahony, Nguyen, Dau, Luong, Le, Nguyen, Nguyen, Portway, Luong & Rowley, 2018 |
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M. huangshanensis Fei & Ye, 2005 |
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M. insularis (Wang, Liu, Lyu, Zeng & Wang, 2017) |
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M. intermedia Smith, 1921 |
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M. jiangi Liu, Li, Wei, Xu, Cheng, Wang & Wu, 2020 | Liu et al. 2020 |
M. jingdongensis Fei & Ye, 1983 |
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M. jinggangensis (Wang, 2012) |
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M. jiulianensis Wang, Zeng, Lyu & Wang, 2019 | Wang et al. 2019 |
M. kalimantanensis Munir, Hamidy, Matsui, Iskandar, Sidik & Shimada, 2019 |
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M. kobayashii Malkmus & Matsui, 1997 |
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M. koui Mahony, Foley, Biju & Teeling, 2017 |
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M. kuatunensis Pope, 1929 |
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M. lancip Munir, Hamidy, Farajallah & Smith, 2018 |
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M. leishanensis Li, Xu, Liu, Jiang, Wei & Wang, 2018 |
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M. lekaguli Stuart, Chuaynkern, Chan-ard & Inger, 2006 |
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M. liboensis (Zhang, Li, Xiao, Li, Pan, Wang, Zhang & Zhou, 2017) |
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M. ligayae Taylor, 1920 |
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M. lini (Wang & Yang, 2014) |
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M. lishuiensis (Wang, Liu & Jiang, 2017) |
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M. longipes Boulenger, 1886 | Taylor 1962 |
M. major Boulenger, 1908 |
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M. mangshanensis Fei & Ye, 1990 |
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M. maosonensis Bourret, 1937 |
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M. medogensis Fei, Ye & Huang, 1983 |
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M. megacephala Mahony, Sengupta, Kamei & Biju, 2011 |
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M. microstoma (Boulenger, 1903) |
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M. minor Stejneger, 1926 |
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M. montana Kuhl & Van Hasselt, 1822 |
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M. monticola (Günther, 1864) |
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M. mufumontana Wang, Lyu & Wang, 2019 | Wang et al. 2019 |
M. nankiangensis Liu & Hu, 1966 |
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M. nankunensis Wang, Zeng & Wang, 2019 | Wang et al. 2019 |
M. nanlingensis Lyu, Wang, Liu & Wang, 2019 | Wang et al. 2019 |
M. nasuta (Schlegel, 1858) | Taylor 1962 |
M. obesa Wang, Li & Zhao, 2014 |
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M. ombrophila Messenger & Dahn, 2019 |
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M. omeimontis Liu, 1950 |
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M. oreocrypta Mahony, Kamei, Teeling & Biju, 2018 |
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M. oropedion Mahony, Teeling & Biju, 2013 |
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M. orientalis Li, Lyu, Wang & Wang, 2020 |
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M. pachyproctus Huang, 1981 |
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M. palpebralespinosa Bourret, 1937 |
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M. parallela Inger & Iskandar, 2005 |
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M. parva (Boulenger, 1893) |
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M. periosa Mahony, Kamei, Teeling & Biju, 2018 |
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M. popei (Zhao, Yang, Chen, Chen & Wang, 2014) |
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M. robusta Boulenger, 1908 |
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M. rubrimera Tapley, Cutajar, Mahony, Chung, Dau, Nguyen, Luong & Rowley, 2017 |
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M. sangzhiensis Jiang, Ye & Fei, 2008 |
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M. serchhipii (Mathew & Sen, 2007) |
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M. shapingensis Liu, 1950 |
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M. shuichengensis Tian & Sun, 1995 |
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M. shunhuangensis Wang, Deng, Liu, Wu & Liu, 2019 |
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M. spinata Liu & Hu, 1973 |
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M. stejnegeri Taylor, 1920 |
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M. synoria (Stuart, Sok & Neang, 2006) |
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M. takensis Mahony, 2011 |
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M. tuberogranulata Shen, Mo & Li, 2010 |
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M. vegrandis Mahony, Teeling & Biju, 2013 |
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M. wawuensis Fei, Jiang & Zheng, 2001 |
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M. wugongensis Wang, Lyu & Wang, 2019 |
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M. wuliangshanensis Ye & Fei, 1995 |
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M. wushanensis Ye & Fei, 1995 |
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M. xianjuensis Wang, Wu, Peng, Shi, Lu & Wu, 2020 |
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M. zhangi Ye & Fei, 1992 |
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M. zunhebotoensis (Mathew & Sen, 2007) |
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Ten advertisement calls from two individuals of the new species were recorded on 18 May 2018 between 21:00–23:00 in Chishui City, Guizhou Province, China in the field. SONY PCM-D50 digital sound recorder was used to record within 20 cm of the calling individuals. The sound files in wave format were resampled at 48 kHz with sampling depth 24 bits. The sonograms and waveforms were generated by WaveSurfer software (
Aligned sequence matrix of 16S+COI and RAG1+BDNF contains 1104 bp and 1582 bp, respectively. ML and BI trees of the mitochondrial DNA dataset presented almost consistent topology (Fig.
Genetic distances on16S gene with uncorrected p-distance model between samples of the undescribed species were below 0.2%. The genetic distance between the undescribed species and its closest related species M. minor was 2.2% on 16S gene, which was higher or at the same level with those among many pairs of congeners, for example, 1.7% between M. spinata Liu & Hu, 1973 and M. sangzhiensis Jiang, Ye & Fei, 2008, 2.1% between M. omeimontis Liu, 1950 and M. binlingensis Jiang, Fei & Ye, 2009, and 2.2% between M. cheni (Wang & Liu, 2014) and M. nankunensis Wang, Zeng & Wang, 2019; Suppl. material
Holotype. CIBCS20190518031 (Figs
Paratype. Two adult males and five adult females from the same place as holotype, collected by Shi-Ze Li and Jing Liu. Two females CIBCS20190518022 and CIBCS20190518023 collected by Jing LIU on 18 May 2019, two adult males CIBCS20190518019 and CIBCS20190518021 and three adult females CIBCS20190518025, CIBCS20190518027 and CIBCS20190518030 collected by Shi-Ze Li on 18 May 2019.
Megophrys chishuiensis sp. nov. is assigned to the genus Megophrys based on molecular phylogenetic analyses and the following generic diagnostic characters: snout shield-like; projecting beyond the lower jaw; canthus rostralis distinct; chest glands small and round, closer to the axilla than to midventral line; femoral glands on rear part of thigh; vertical pupils (
Megophrys chishuiensis sp. nov. could be distinguished from its congeners by a combination of the following morphological characters: (1) body size moderate (SVL 43.4–44.1 mm in males, and 44.8–49.8 mm in females; (2) vomerine teeth absent; (3) tongue not notched behind; (4) a small horn-like tubercle at the edge of each upper eyelid; (5) tympanum distinctly visible, rounded; (6) two metacarpal tubercles on palm; (7) relative finger lengths II < I < V < III; (8) toes without webbing; (9) heels overlapping when thighs are positioned at right angles to the body; (10) tibiotarsal articulation reaching the level between tympanum and eye when leg stretched forward. In breeding male, (11) an internal single subgular vocal sac; (12) nuptial pads with black spines on dorsal surface of bases of the first two fingers.
(Figs
Forelimbs slender, the length of lower arm and hand 42.4% of SVL; fingers slender, relative finger lengths: II < I < V < III; tips of digits globular, without lateral fringes; subarticular tubercle distinct at the base of each finger; two metacarpal tubercles, prominent, the outer one long and thin, the inner one oval-shaped.
Hindlimbs slender, 1.48 times SVL; heels overlapping when thighs are positioned at right angles to the body, tibiotarsal articulation reaching tympanum to eye when leg stretched forward; tibia length longer than thigh length; relative toe lengths I < II < V < III < IV; tips of toes round, slightly dilated; subarticular tubercles absent; toes without webbing; no lateral fringe; inner metatarsal tubercle oval-shaped; outer metatarsal tubercle absent.
Dorsal skin rough, with numerous granules; several large warts scattered on flanks; a small horn-like tubercle at the edge of each upper eyelid; tubercles on the dorsum forming a weak X-shaped ridge, the V-shaped ridges disconnect; two discontinuous dorsolateral parallel ridges on either side of the X-shaped ridges; an inverted triangular brown speckle between two upper eyelids; several tubercles on the flanks and dorsal surface of thighs and tibias and forming four transverse tubercle rows; supratympanic fold distinct.
Ventral surface smooth; chest with small and round glands, closer to the axilla than to midventral line; femoral glands on rear of thighs, numerous white granules on outer thighs; posterior end of the body distinctly protruding and forming an arc-shaped swelling above the anal region.
(Fig.
(Fig.
In CIBCS20190518027, the back is brown with some brick-red granules (Fig.
Color variation in Megophrys chishuiensis sp. nov. A dorsolateral view of the female specimen CIBCS20190518027 B dorsolateral view of the female specimen CIBCS20190518030 C dorsal view of the female specimen CIBCS20190518025 D ventral view of the male specimen CIBCS20190518019 E ventral view of the female specimen CIBCS20190518030 F ventral view of the female specimen CIBCS20190518025.
The call description is based on recordings of the holotype CIBCS20190518031 (Fig.
Adult females with SVL 44.8–49.8 mm, larger than adult males with 43.4–44.1 mm. Adult males have a single subgular vocal sac. In breeding males, brownish red nuptial pads are present on dorsal surface of the bases of the first and second fingers with black spines obvious under microscope.
By having medium body size, Megophrys chishuiensis sp. nov. differs from M. aceras Boulenger, 1903, M. auralensis Ohler, Swan & Daltry, 2002, M. carinense Boulenger, 1889, M. caudoprocta Shen, 1994, M. chuannanensis (Fei, Ye & Huang, 2001), M. damrei Mahony, 2011, M. edwardinae Inger, 1989, M. feae Boulenger, 1887, M. flavipunctata Mahony, Kamei, Teeling & Biju, 2018, M. gigantica Liu, Hu & Yang, 1960, M. glandulosa Fei, Ye & Huang, 1990, M. himalayana Mahony, Kamei, Teeling & Biju, 2018, M. intermedia Smith, 1921, M. jingdongensis Fei & Ye, 1983, M. kalimantanensis Munir, Hamidy, Matsui, Iskandar, Sidik & Shimada, 2019, M. lekaguli Stuart, Chuaynkern, Chan-ard & Inger, 2006, M. liboensis (Zhang, Li, Xiao, Li, Pan, Wang, Zhang & Zhou, 2017), M. major Boulenger, 1908, M. mangshanensis Fei & Ye, 1990, M. maosonensis Bourret, 1937, M. medogensis Fei, Ye & Huang, 1983, M. omeimontis Liu, 1950, M. oreocrypta Mahony, Kamei, Teeling & Biju, 2018, M. orientalis (Li, Lyu, Wang & Wang, 2020), M. periosa Mahony, Kamei, Teeling & Biju, 2018, M. popei (Zhao, Yang, Chen, Chen & Wang, 2014), M. sangzhiensis Jiang, Ye & Fei, 2008, M. shapingensis Liu, 1950, M. shuichengensis Tian & Sun, 1995, and M. takensis Mahony, 2011 (maximum SVL < 49.8 mm in the new species vs. minimum SVL > 53 mm in the latter), and differs from M. acuta Wang, Li & Jin, 2014, M. angka (Wu, Suwannapoom, Poyarkov, Chen, Pawangkhanant, Xu, Jin, Murphy & Che, 2019), M. caobangensis Nguyen, Pham, Nguyen, Luong & Ziegler, 2020, M. damrei Mahony, 2011, M. dongguanensis Wang & Wang, 2019, M. cheni, M. jiangi, M. jinggangensis (Wang, 2012), M. jiulianensis Wang, Zeng, Lyu & Wang, 2019, M. kuatunensis Pope, 1929, M. lini (Wang & Yang, 2014), M. lishuiensis (Wang, Liu & Jiang, 2017), M. mufumontana (Wang, Lyu & Wang, 2019), M. minor, M. nanlingensis (Lyu, Wang, Liu & Wang, 2019), M. obesa Wang, Li & Zhao, 2014, M. pachyproctus Huang, 1981, M. palpebralespinosa Bourret, 1937, M. serchhipii Mathew & Sen, 2007, M. shunhuangensis Wang, Deng, Liu, Wu & Liu, 2019, M. vegrandis Mahony, Teeling & Biju, 2013, M. wuliangshanensis Ye & Fei, 1995, M. wushanensis Ye & Fei, 1995, M. zunhebotoensis Mathew & Sen, 2007, M. xianjuensis Wang, Wu, Peng, Shi, Lu & Wu, 2020, and M. zhangi Ye & Fei, 1992 (vs. maximum SVL < 42 mm in the latter).
By the absence of vomerine teeth, Megophrys chishuiensis sp. nov. differs from M. aceras, M. ancrae Mahony, Teeling & Biju, 2013, M. carinense, M. baluensis (Boulenger, 1899), M. caudoprocta, M. chuannanensis, M. damrei, M. daweimontis Rao & Yang, 1997, M. dongguanensis, M. fansipanensis Tapley, Cutajar, Mahony, Nguyen, Dau, Luong, Le, Nguyen, Nguyen, Portway, Luong & Rowley, 2018, M. flavipunctata, M. glandulosa, M. hoanglienensis Tapley, Cutajar, Mahony, Nguyen, Dau, Luong, Le, Nguyen, Nguyen, Portway, Luong & Rowley, 2018, M. himalayana, M. insularis (Wang, Liu, Lyu, Zeng & Wang, 2017), M. intermedia, M. jingdongensis, M. jinggangensis, M. jiulianensis. M. kalimantanensis, M. kobayashii Malkmus & Matsui, 1997, M. lancip Munir, Hamidy, Farajallah & Smith, 2018, M. lekaguli, M. liboensis, M. ligayae Taylor, 1920, M. longipes Boulenger, 1886, M. major, M. mangshanensis, M. maosonensis, M. medogensis, M. megacephala Mahony, Sengupta, Kamei & Biju, 2011, M. montana Kuhl & Van Hasselt, 1822, M. nasuta (Schlegel, 1858), M. nankunensis, M. nanlingensis, M. omeimontis, M. oropedion Mahony, Teeling & Biju, 2013, M. oreocrypta, M. palpebralespinosa, M. parallela Inger & Iskandar, 2005, M. parva (Boulenger, 1893), M. periosa, M. popei, M. robusta Boulenger, 1908, M. rubrimera Tapley, Cutajar, Mahony, Chung, Dau, Nguyen, Luong & Rowley, 2017, M. sangzhiensis, M. stejnegeri Taylor, 1920, M. takensis, M. zhangi, and M. zunhebotoensis (vs. present in the latter).
By having a small horn-like tubercle at the edge of each upper eyelid, Megophrys chishuiensis sp. nov. differs from M. binchuanensis Ye & Fei, 1995, M. binlingensis, M. damrei, M. gigantica, M. minor, M. monticola (Günther, 1864), M. nasuta, M. nankiangensis Liu & Hu, 1966, M. oropedion, M. pachyproctus, M. spinata, M. stejnegeri, M. takensis, M. wuliangshanensis, M. wushanensis, M. zhangi, and M. zunhebotoensis (vs. lacking tubercle in the latter), and differs from M. carinense, M. feae, M. gerti (Ohler, 2003), M. hansi (Ohler, 2003), M. intermedia, M. kalimantanensis, M. koui Mahony, Foley, Biju & Teeling, 2017, M. latidactyla, M. liboensis, M. microstoma (Boulenger, 1903), M. palpebralespinosa, M. popei, M. shuichengensis, and M. synoria (Stuart, Sok & Neang, 2006) (vs. having a prominent and elongated tubercle in the latter).
By having a tongue not notched behind, Megophrys chishuiensis sp. nov. differs from M. ancrae, M. baolongensis Ye, Fei & Xie, 2007, M. binlingensis, M. boettgeri (Boulenger, 1899), M. carinense, M. cheni, M. chuannanensis, M. damrei, M. dringi Inger, Stuebing & Tan, 1995, M. fansipanensis, M. feae, M. feii Yang, Wang & Wang, 2018, M. flavipunctata, M. gerti, M. glandulosa, M. hoanglienensis, M. huangshanensis Fei & Ye, 2005, M. insularis, M. jiulianensis. M. jingdongensis, M. kalimantanensis, M. kuatunensis, M. liboensis, M. mangshanensis, M. maosonensis, M. medogensis, M. minor, M. nankiangensis, M. nanlingensis, M. omeimontis, M. oropedion, M. pachyproctus, M. parallela, M. popei, M. robusta, M. sangzhiensis, M. shapingensis, M. shuichengensis, M. spinata, M. vegrandis, M. wawuensis Fei, Jiang & Zheng, 2001, M. zhangi, and M. zunhebotoensis (vs. tongue notched behind in the latter).
By lacking lateral fringes on the toes, Megophrys chishuiensis sp. nov. differs from M. acuta, M. auralensis, M. baolongensis, M. binchuanensis, M. boettgeri, M. carinense, M. cheni, M. chuannanensis, M. elfina Poyarkov, Duong, Orlov, Gogoleva, Vassilieva, Nguyen, Nguyen, Nguyen, Che & Mahony, 2017, M. feae, M. feii, M. flavipunctata, M. gigantica, M. glandulosa, M. hansi, M. intermedia, M. jingdongensis, M. jinggangensis, M. kuatunensis, M. latidactyla, M. lini, M. major, M. maosonensis, M. nankiangensis, M. omeimontis, M. palpebralespinosa, M. popei, M. rubrimera, M. sangzhiensis, M. serchhipii, M. shapingensis, M. shuichengensis, M. spinata, M. vegrandis, M. xianjuensis, M. zhangi, and M. zunhebotoensis (vs. present in these species).
By having toes without webs at bases, Megophrys chishuiensis sp. nov. differs from M. brachykolos Inger & Romer, 1961, M. carinense, M. flavipunctata, M. jingdongensis, M. jinggangensis, M. lini, M. major, M. palpebralespinosa, M. popei, M. shuichengensis, M. spinata (vs. at least one-fourth webbed).
By heels overlapping when thighs are positioned at right angles to the body, Megophrys chishuiensis sp. nov. differs from M. acuta, M. brachykolos, M. dongguanensis, M. huangshanensis, M. kuatunensis, M. nankunensis, M. obesa, M. ombrophila Messenger & Dahn, 2019, and M. wugongensis Wang, Lyu & Wang, 2019 (vs. not meeting).
With tibiotarsal articulation reaching to the level between tympanum and eye when leg is stretched forward, Megophrys chishuiensis sp. nov. differs from M. baolongensis, M. nankiangensis, M. pachyproctus, M. shuichengensis and M. tuberogranulata Shen, Mo & Li, 2010 (vs. just reaching posterior corner of the eye in the latter); differs from M. daweimontis, M. glandulosa, M. lini, M. major, M. medongensis, M. obesa, and M. sangzhiensis (vs. reaching the anterior corner of the eye or beyond eye or nostril and tip of snout in the latter); differs from M. leishanensis Li, Xu, Liu, Jiang, Wei & Wang, 2018 (vs. reaching middle part of eye in this group of species); and differs from M. mufumontana (vs. reaching tympanum in males and to the eye in females).
By having an internal single subgular vocal sac in male, Megophrys chishuiensis sp. nov. differs from M. caudoprocta, M. shapingensis, and M. shuichengensis (vs. vocal sac absent).
By having nuptial pads and nuptial spines on dorsal surface of the base of the first two fingers in breeding males, Megophrys chishuiensis sp. nov. differs from M. acuta, M. feii, M. shapingensis, and M. shuichengensis (vs. lacking in these species).
The congeners M. carinense, M. jiangi, M. leishanensis, M. liboensis, M. shuichengensis, and M. spinata have sympatric distribution with Megophrys chishuiensis sp. nov. (
Megophrys chishuiensis sp. nov. is phylogenetically closest to M. minor, and this new species could be identified from the latter distinctly by having larger body size (SVL 43.4–44.1 mm in males vs. 34.5–41.2 mm in males of M. minor), having a small horn-like tubercle at the edge of each upper eyelid (vs. absent in the latter), tongue not notched behind (vs. notched in the latter), tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward (vs. reaching the level between eye and tip of snout in the latter), and having two metatarsal tubercles in each hand (vs. absent in the latter).
Megophrys chishuiensis sp. nov. is known from the type locality, Chishui National Nature Reserve (28.38–28.45N, 106.05–109.75E), Chishui City, Guizhou Province, China at elevations between 270–604 m. The individuals of the new species were frequently found in bamboo forest nearby the streams (Fig.
The specific name chishuiensis refers to the distribution of this species, Chishui City, Guizhou Province, China. We propose the common name “Chishui horned toad” and its Chinese name as Chi Shui Jiao Chan (赤水角蟾).
The new species, Megophrys chishuiensis sp. nov., resembles M. minor and M. jiangi, and detailed comparison with different data sets are important for recognizing them. Our molecular phylogenetic data on mitochondrial DNA and nuclear DNA, and morphological comparisons both separated the new species from the two closely related species. Megophrys minor were reported to be distributed widely through the provinces of Sichuan, Guizhou, Chongqing, Yunnan, Guangxi, Jiangxi and north of Vietnam (
Megophrys chishuiensis sp. nov. with a narrow distribution also fits the “micro-endemism” model like many other congeners (
We are grateful to editors and reviewers for their work on this manuscript. This work was supported by Laboratory on Biodiversity Conservation and Applied Ecology of Guiyang College GYU-KYZ (2019~2020) PT14–02, National Natural Sciences Foundation of China (NSFC31960099), Biodiversity Conservation Key Laboratory of Guizhou Province Education Department, Guiyang College, Basic research project of science and technology department of Guizhou Province (Nos. [2020] 1Y083), Science and technology support project of science and technology department of Guizhou Provincial (No. [2020] 4Y029) and Guizhou Provincial Department of Education Youth Science and Technology Talents Growth Project (Nos. KY[2018]455 and KY[2018]468).
Table S1
Explanation note: Measurements of the adult specimens of Megophrys chishuiensis sp. nov.
Table S2
Explanation note: Localities, voucher information, and GenBank accession numbers for molecular samples used in this study.
Table S3
Explanation note: Primer sequences used in this study.
Table S4
Explanation note: Uncorrected p-distances between the Megophrys species based on the 16S gene sequences.