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| Brachytarsophrys orientalis Y. Li, Lyu, J. Wang & Y.Y. Wang
in Li, Zhang, Lyu, ... et Wang, 2020.
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Abstract
The genus-level recognition of monophyletic short-legged toads (Brachytarsophrys) has been recently implicated in the taxonomic debate of Megophrys sensu lato. In the present study, Brachytarsophrys is reasonably regarded as a distinct genus based on significant morphological differentiations and recent molecular analyses. Furthermore, a comprehensive review of this genus is performed, with two species groups proposed based on morphological differences and phylogenetic relationships. Particularly, Brachytarsophrys platyparietus is removed as a synonym of Brachytarsophrys carinense and considered a valid species due to significant genetic divergence and distinct morphological differences. In addition, a new species, Brachytarsophrys orientalis sp. nov., is described based on a series of specimens collected from southeastern China. This work takes the member species of the genus Brachytarsophrys to seven, suggesting that the diversity of Brachytarsophrys is underestimated. In addition, the genus levels of other monophyletic groups within the subfamily Megophryinae are discussed.
Key words: Genus level, Megophryinae, Morphology, Phylogeny, Revision
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| Figure 1. Collection localities of samples used in this study. Localities of Brachytarsophrys orientalis sp. nov.: 1: Huboliao Nature Reserve, Fujian; 2: Shanghang County, Fujian; 3: Jiulianshan Nature Reserve, Jiangxi. Localities of B. popei; 4: Taoyuandong Nature Reserve, Hunan. Localities of B. chuannanensis; 5: Hejiang County, Sichuan. Localities of B. platyparietus; 6: Mt. Fanjing, Guizhou; 7: Mt. Jinzhong, Guangxi; 8: Shiping County, Yunnan; 9: Mt. Mopan, Yunnan; 10: Dayao County, Yunnan; 11: Yanbian County, Yunnan. Localities of B. feae; 12: Jingdong County, Yunnan. Localities of B. carinense; 13: Mae Surin NP., Mae Hong Son, Thailand; 14: Omkoi, Chiang Mai, Thailand; 15: Thong Pha Phum, Kanchanaburi, Thailand. Localities of B. intermedia; 16: Krong Pa, Gia Lai, Vietnam. |
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| Figure 1. Collection localities of samples used in this study and habitat of Brachytarsophrys orientalis sp. nov. A: Localities of Brachytarsophrys orientalis sp. nov.: 1: Huboliao Nature Reserve, Fujian; 2: Shanghang County, Fujian; 3: Jiulianshan Nature Reserve, Jiangxi. Localities of B. popei; 4: Taoyuandong Nature Reserve, Hunan. Localities of B. chuannanensis; 5: Hejiang County, Sichuan. Localities of B. platyparietus; 6: Mt. Fanjing, Guizhou; 7: Mt. Jinzhong, Guangxi; 8: Shiping County, Yunnan; 9: Mt. Mopan, Yunnan; 10: Dayao County, Yunnan; 11: Yanbian County, Yunnan. Localities of B. feae; 12: Jingdong County, Yunnan. Localities of B. carinense; 13: Mae Surin NP., Mae Hong Son, Thailand; 14: Omkoi, Chiang Mai, Thailand; 15: Thong Pha Phum, Kanchanaburi, Thailand. Localities of B. intermedia; 16: Krong Pa, Gia Lai, Vietnam. B: Habitat of Brachytarsophrys orientalis sp. nov. in Jiulianshan Nature Reserve, Jiangxi Province. |
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| Figure 3. Bayesian inference and maximum-likelihood phylogenies Numbers before slashes are Bayesian posterior probabilities, and numbers after slashes are maximum-likelihood bootstrap supports. |
SYSTEMATICS
Family Megophryidae Bonaparte, 1850
Subfamily Megophryinae Bonaparte, 1850
Genus Brachytarsophrys Tian & Hu, 1983
Type species: Leptobrachium carinense Boulenger, 1889
Diagnosis: (1) Large body size, habitus thickset and stout; (2) head enormous, and extremely depressed, head width approximately twice skull length; (3) presence of transverse groove, defining head behind; (4) tympanum hidden; (5) maxillary teeth present; (6) pupil vertical; (7) upper eyelid with several conical tubercles, one elongated, forming conical or flattened horn; (8) hindlimbs short and strongly thickset, heels not meeting, separated by greater distance; (9) toes with webbing and fringes; (10) inhabits deep crevices between rocks or boulders of streams during breeding season.
Suggested common name: Short-Legged Toads (in English) / Duan Tui Chan (短腿蟾 in Chinese).
Distribution: Tropical and subtropical eastern and southeastern mainland Asia, including southern China, Myanmar, Vietnam, Laos, and northern Thailand.
Remarks: The genus Brachytarsophrys was established with designating Leptobrachium carinense Boulenger, 1889 as the type species (Tian & Hu, 1983). However, from the original literature, the examined specimen of L. carinense by Tian & Hu (1983) was collected from Jingdong, Yunnan, China, and should not be identified as B. carinense but as B. feae (Boulenger, 1886).
Brachytarsophrys carinense group
Brachytarsophrys carinense (Boulenger, 1889)
Leptobrachium carinense: Boulenger, 1889.
Megophrys carinensis: Bourret, 1942.
Brachytarsophrys carinensis: Tian & Hu, 1983; Rao & Yang, 1997.
Megophrys (Brachytarsophrys) carinensis: Dubois, 1987.
Brachytarsophrys carinense: Delorme et al., 2006.
Megophrys (Brachytarsophrys) carinense: Mahony et al., 2017.
Syntypes: BMNH and NHMW 2291.1-2 (according to Häupl & Tiedemann (1978)) and MSNG 29689 (designated lectotype by Capocaccia (1957)), collected from western slopes of Karens Mountains (800 m a.s.l.), East of Toungoo, Myanmar.
Diagnosis: Based on the original description of Boulenger (1889) and supplementary description of Taylor (1962) and Mahony et al. (2017). (1) Large body size, SVL 124.0–168.0 mm in females, 91.6–123.0 mm in males; (2) head enormous, extremely depressed, head width nearly twice skull length; (3) tongue large, feebly notched behind; (4) canthus rostralis distinct, loreal region to temporal region very oblique; (5) tympanum hidden; (6) maxillary teeth present, vomerine teeth present on two widely-separated vomerine ridges; (7) digits without subarticular tubercles, tibiotarsal articulation reaching axilla in females, commissure of mouth in males; (8) very large, flat, oval inner metatarsal tubercle; (9) toes one third webbed; (10) presence of transverse fold separating head from body; (11) upper eyelid with two to four horn-like conical tubercles; (12) oblique dermal ridge on each side of anterior part of dorsum; (13) stellate bony deposits in skin of parietal region and anterior part of dorsum; (14) single subgular vocal sac in males.
Suggested common name: Broad-Headed Short-Legged Toad (in English) / Kuan Tou Duan Tui Chan (宽头短腿蟾 in Chinese). อึ่งกรายข้างแถบ
Distribution and habitats: Currently, B. carinense is recognized from southern Myanmar and adjacent northern Thailand at elevations of 800 m and upwards. This toad hides in crevices between rocks or between the roots of shrubs during the day (Boulenger, 1889; Taylor, 1962).
Brachytarsophrys intermedia (Smith, 1921)
Megalophrys intermedius: Smith, 1921.
Megophrys intermedia: Bourret, 1942.
Brachytarsophrys intermedia: Rao & Yang, 1997.
Megophrys (Brachytarsophrys) intermedia: Mahony et al., 2017.
Diagnosis: Based on the original description of Smith (1921). (1) Medium body size, SVL 92.0 mm in one adult female, 86.0–103.0 mm in seven adult males; (2) head enormous and depressed, head width nearly twice skull length; (3) tongue feebly notched behind; (4) maxillary teeth present, vomerine teeth present on two widely-separated vomerine ridges; (5) snout round, not protruding beyond margin of lower jaw, canthus rostralis distinct; (6) loreal region to temporal region very oblique; (7) tympanum hidden; (8) presence of transverse groove behind head, separating head from body; (9) digits without subarticular tubercles, tibiotarsal articulation reaching to commissure of jaw; (10) large, flat, oval inner metatarsal tubercles; (11) toes one third to one half webbed, web extending as fringe along either side of toes; (12) paired oblique glandular folds on dorsum; (13) upper eyelid with several conical tubercles, one enlarged to form long horn.
Suggested common name: Annam Short-Legged Toad (in English) / Yue Nan Duan Tui Chan (越南短腿蟾 in Chinese).
Distribution and habitats: The species occurs in the central highlands of southern Vietnam and Laos at elevations above 900 m. Most specimens have been discovered in deep crevices between the rocks or boulders of streams. Loud, harsh male croaks can be heard at all times of the day and night (Smith, 1921).
Brachytarsophrys feae group
Brachytarsophrys chuannanensis Fei, Ye & Huang, 2001
Suggested common name: Southern Sichuan Short-Legged Toad (in English) / Chuan Nan Duan Tui Chan (川南短腿蟾 in Chinese).
Distribution and habitats: The species is distributed in Hejiang and Junlian counties, Sichuan Province, southwestern China, at 800 to 1 400 m a.s.l.. Specimens are found in or near montane streams surrounded by lush vegetation. They usually hide in crevices between rocks or dirt burrows in streams during the day. Males emit a series of croaks at about 23:00h. The spawning season is around the middle of May (Fei & Ye, 2001).
Brachytarsophrys feae (Boulenger, 1886)
Megalophrys feae: Boulenger, 1886.
Leptobrachium feae: Boulenger, 1889.
Megophrys feae: Gee & Boring, 1929.
Brachytarsophrys feae: Rao & Yang, 1997.
Megophrys (Brachytarsophrys) feae: Mahony et al., 2017.
Holotype: MSNG 29763, female (according to Capocaccia (1957)), collected from Khakhyen Hills, East of Bhamò, Myanmar.
Diagnosis: Based on the original description of Boulenger (1886), supplementary description of Fei et al. (2009), and examined specimens. (1) Moderate body size, SVL 78.5–94.9 mm in five adult males; (2) head enormous, extremely depressed, head width approximately twice skull length; (3) tongue pyriform, feebly notched behind; (4) maxillary teeth present, vomerine teeth present on two vomerine ridges; (5) canthus rostralis indistinct, loreal region concave, temporal region oblique; (6) tympanum hidden; (7) tibiotarsal articulation reaching axilla or commissure of jaw; (8) very large, flat, oval inner metatarsal tubercle, longer than first toe; (9) toes with rudimentary webbing; (10) upper eyelid with several small tubercles, one enlarged, forming horn; (11) absence of dermal ridge on dorsum; (12) stellate bony deposits on each side of parietal region; (13) male with single subgular vocal sac, dorsal surface of first and second finger bases with black brown nuptial pad; (14) tadpole with several transversal stripes on ventral surface.
Suggested common name: Fea’s Short-Legged Toad (in English) / Fei Shi Duan Tui Chan (费氏短腿蟾 in Chinese). อึ่งกรายพม่า
Distribution and habitats: This species is currently recognized from northern Myanmar and Yunnan Province in southwestern China at 650 to 2 100 m a.s.l.. Specimens are found in montane streams, under rocks or deep burrows surrounded by moist evergreen broadleaf forests. Male individuals begin to emit a series of croaks in April. The spawning season is from May to June (Fei & Ye, 2009; this study).
Brachytarsophrys popei Zhao, Yang, Chen, Chen & Wang, 2014 (Figure 7)
Suggested common name: Pope’s Short-Legged Toad (in English) / Po Pu Duan Tui Chan (珀普短腿蟾 in Chinese).
Distribution and habitats: Brachytarsophrys popei populations occur in Taoyuangdong Nature Reserve, Hunan Province, adjacent Mt. Jinggang, Jiangxi Province, and Nanling Reserve, Guangdong Province, southeastern China, at 900 to 1 300 m a.s.l.. The species can be found under rocks in montane streams surrounded by moist subtropical evergreen broadleaf forests. Males emit a series of croaks from July to September (Zhao et al., 2014).
Brachytarsophrys platyparietus Rao & Yang, 1997
Suggested common name: Flat-Headed Short-Legged Toad (in English) / Ping Tou Duan Tui Chan (平头短腿蟾 in Chinese).
Distribution and habitats: Currently, Brachytarsophrys platyparietus is recognized from Duodihe of Dayao County, Mt. Mopan of Xinping County, Yilong Township of Shiping County, Mt. Jinzhong of Longlin County, Mt. Fanjing of Tongren City, Yumen Township of Yanbian County, indicating its potential distribution areas, which range across central southwestern China at around 2 000 m a.s.l.. These toads inhabit montane streams surrounded by moist subtropical evergreen broadleaf forests. Some adult males have been found near batches of eggs attached to the bottom of a rock, suggesting that adult males may exhibit egg protection behavior (Figure 10).
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| Figure 11. General aspect of Brachytarsophrys orientalis sp. nov. A: Dorsolateral view of adult male holotype SYS a004227 in life; B: Ventral view of holotype SYS a004227 in life; C, D: Hand and foot of holotype SYS a004227 in life. |
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| Figure 12. Morphological differences between Brachytarsophrys orientalis sp. nov. and B. popei A: Sole of feet in male holotype SYS a004227 of Brachytarsophrys orientalis sp. nov.; B: Sole of feet in female paratype SYS a004486 of Brachytarsophrys orientalis sp. nov.; C: Sole of feet in male holotype SYS a001867 of B. popei; D: Sole of feet in female paratype SYS a001875 of B. popei; E, F: Ventral view of 36th stage tadpole of Brachytarsophrys orientalis sp. nov. |
Brachytarsophrys orientalis sp. nov. Y. Li, Lyu, J. Wang & Y.Y. Wang
Diagnosis: Brachytarsophrys orientalis sp. nov. is characterized by the following combination of morphological characters: (1) relatively small body size, SVL 88.6 mm in single adult female, SVL 76.8–82.7 mm in seven adult males; (2) head enormous and depressed, head width nearly 1.2 times as long as head length and nearly twice skull length; (3) tongue pyriform, feebly notched behind; (4) heels not meeting; (5) tibiotarsal articulation reaching to commissure of jaw; (6) outer metatarsal tubercle absent, inner metatarsal tubercle approximately equal to first toe; (7) smaller webbing, from distal metatarsals to basal toes, webbing formula I (1½)-(2) II (1½)-(3) III (2½)-(4) IV (4)-(2) V in males; (8) lateral fringes of males more developed than those of females, nearly one third as broad as distal toe phalanx in males; (9) absence of a transversal stripe on chest in tadpole.
Male secondary sexual characteristics: Male with single subgular vocal sac; nuptial pad on dorsal surface of first and second fingers, nuptial spines black (in preservative).
Etymology: The specific name “orientalis” refers to the distribution of the new species, which is the easternmost species within the genus Brachytarsophrys.
Suggested common name: Oriental Short-Legged Toad (in English) / Dong Fang Duan Tui Chan (东方短腿蟾 in Chinese).
Distribution and habitats: Currently, Brachytarsophrys orientalis sp. nov. is only known from the Jiulianshan Nature Reserve in Jiangxi Province and Gutian Township and Huboliao Nature Reserve in Fujian Province, China, at 200 to 700 m a.s.l.. This species is found under rocks in montane streams surrounded by moist subtropical evergreen broadleaf forests (Figure 1B). All male individuals were observed in August and emitted a series of croaks from hidden positions.
Yao Li, Dan-Dan Zhang, Zhi-Tong Lyu, Jian Wang, Yu-Long Li, Zu-Yao Liu, Hong-Hui Chen, Ding-Qi Rao, Zhi-Fang Jin, Chang-You Zhang and Ying-Yong Wang. 2020. Review of the Genus Brachytarsophrys (Anura: Megophryidae), with Revalidation of Brachytarsophrys platyparietus and Description of A New Species from China. Zoological Research. 41(2); 105-122. DOI: 10.24272/j.issn.2095-8137.2020.033
