Amolops yangi Wu, Yu, Lu, Yuan & Che, 2024

Wu, Yun-He, Yu, Zhong-Bin, Lu, Chen-Qi, Zhang, Yin-Peng, Dong, Wen-Jie, Liu, Xiao-Long, Kilunda, Felista Kasyoka, Xiong, Yun, Jiang, Yun-Fang, Ouyang, Hong, Fu, Zhong-Xiong, He, Yun-Biao, Yuan, Zhi-Yong & Che, Jing, 2024, A new species of the genus Amolops (Amphibia: Ranidae) and the first national record of Amolops vitreus from China, Vertebrate Zoology 74, pp. 343-357 : 343

Amolops yangi Wu, Yu, Lu, Yuan & Che sp. nov.

Holotype.

Adult female (KIZ 038643), from Ega, Lushui, Nujiang Lisu Autonomous Prefecture, Yunnan Province, China (26.43744°N, 98.75044°E; elevation 3496 m a.s.l.), collected by Zhong-Bin Yu, Dong An, Tian-En Chen on 07, August, 2021.

Paratypes.

One adult male KIZ 038645 from Ega, Lushui, Nujiang Lisu Autonomous Prefecture, Yunnan Province, China (26.44924°N, 98.76762°E; elevation 2915 m a.s.l.), collected by Zhong-Bin Yu, Dong An, Tian-En Chen on 07, August, 2021; one adult male KIZ 050788 from Yaping road, Lumadeng Township, Fugong county, Nujiang Lisu Autonomous Prefecture, Yunnan Province, China (27.15890°N, 98.79712°E; elevation 2451 m a.s.l.), collected by Zhong-Bin Yu, Dong An on 05, August, 2022.

Etymology.

The specific epithet " yangi " is a patronymic noun in the genitive singular; derived from the name of Prof. Da-Tong Yang of the Kunming Institute of Zoology, CAS, China. We acknowledge his great contributions to the herpetological research in southwestern China. We suggest the Chinese formal name as “杨氏湍蛙”.

Diagnosis.

Amolops yangi sp. nov. is assigned to the genus Amolops based on molecular phylogenetic analyses and can be distinguished from its congeners by a combination of the following characters: (1) medium body size (SVL 46.3-51.8 mm in males and at least 51.5 mm in female); (2) vomerine teeth developed, on two short oblique between choanae, equal in distance from each other as to choanae; (3) supernumerary tubercles present at the base of each finger; (4) tympanum indistinct; (5) three metacarpal tubercles, inner metacarpal tubercle long, outer metacarpal tubercle relatively small, oval, median one rounded; (6) supratympanic fold indistinct; (7) discontinuous glandular dorsolateral fold from rear of eye to near vent; (8) circummarginal grooves present on tips of outer three fingers, absent on first finger; (9) iris distinctly bicolored, golden-yellow in upper one-fourth and reddish brown in lower three-fourths, black reticulations throughout; (10) rictal gland absent; (11) dorsal surface of the head, back, limbs, fingers, and toes green, interspersed with irregular black spots; (12) dorsal parts of limbs, fingers and toes with black crossbars; (13) vocal sac absent in males; (14) male with orange nuptial pad at the base of first finger.

Description of holotype

(all measurements in mm; see Table 1 ). KIZ 038643, sexually mature female, body size moderate, adult female (SVL 51.5 mm); head length larger than wide (HL/SVL 34.2%, HW/SVL 32.6%); top of head flat; snout short (SL/HL 46.0%), snout rounded in dorsal view (Fig. 4A ), obtusely rounded in profile, projecting beyond margin of lower jaw; loreal region and concave and oblique; canthus rostralis distinct, slightly constricted behind nostrils; dorsal region of snout flattened; eyes relatively large (ED/HL 29.0%), slightly protuberant in dorsal view and notably protruding in profile (Fig. 4A ), eye diameter shorter than snout length (ED/SL 63.0%); nostrils oval, laterally orientated, slightly protuberant, closer to anterior corner of eye than to tip of snout; pupil oval, horizontal; tympanum indistinct, circular in shape, relatively small (TD/HL 10.2%), tympanum diameter about one third of eye diameter (TD/ED 35.3%); internarial distance (INS/SVL 13.4%) larger than width of upper eyelid (INS/UEW 168.3%) and interorbital distance (INS/IOS 160.5%); tongue cordiform, deeply notched posteriorly; vomerine teeth developed, on two short oblique between choanae, equal in distance from each other as to choanae; choanae oval; maxillary teeth developed; a small tooth-like projection on anteromedial edge of mandible.

Forelimbs moderately long and robust, forelimb and hand length (29.1 mm) longer than half body size (LAHL/SVL 56.5%); relative length of fingers: I<II<IV<III; circummarginal grooves present on tips of outer three fingers, absent on first finger; subarticular tubercles prominent and oval, formula 1, 1, 2, 2; supernumerary tubercles present at the base of each finger; webbing between fingers absent; narrow lateral fringes of fingers III and IV; three metacarpal tubercles, inner metacarpal tubercle long, outer metacarpal tubercle relatively small, oval, median one rounded (Fig. 4D ).

Hindlimbs long and robust, femoral length shorter than the tibia length (FEM/TIB 93.0%) and the foot length (FEM/FTL 90.4%); tibiotarsal articulation of adpressed limb reaching between nostrils and eyes when hindlimb stretched alongside of body; the heels overlapping when the tibias are perpendicular to the body axis; relative toes lengths: I<II<III<V<IV; narrow lateral fringes of preaxial side of toe I and postaxial side of toe V; tips of all toes expanded into discs with circummarginal grooves; toes fully webbed except for fourth toe, in which web reaches beyond distal subarticular tubercle; subarticular tubercles oval and distinct, formula 1, 1, 2, 3, 2; supernumerary tubercles absent; inner metatarsal tubercle long, outer metatarsal tubercle absent (Fig. 4E ).

Dorsal surface of head, body, limbs, fingers, toes and flank of body relatively smooth; loreal region densely scattered with raised tubercles; temporal region and posterior angle of the jaw with dense tubercles; skin ventrally smooth, including throat, chest, abdomen, and ventral surface of limbs; discontinuous glandular dorsolateral fold from rear of eye to near vent; supratympanic fold indistinct; rictal gland absent (Fig. 4A-E ).

Color of holotype in life.

For coloration of the holotype in life see Figure 4A-E . Dorsal surface of the head, back, limbs, fingers, and toes green, interspersed with irregular black spots; throat, ventral surface of the head, chest and anterior abdomen mostly yellow, with scattered grayish spots; upper part of flanks green, lower part of flanks green-yellow; a black stripe below edge of the canthus rostralis extending from the snout tip across the eyes, to the anterior edge of supratympanic fold; upper lips with three dark bars; ventral surface of thighs orangish, densely scattered with small yellow spots; dorsal parts of limbs, fingers and toes with black crossbars; ventral surface of fingers and toes orange; toes webbing yellowish-gray; the inside of lower arm with black stripe; ventral surface of all fingers discs, subarticular tubercles, supernumerary tubercles, and metacarpal tubercles orange, ventral surface of outer three toes discs, subarticular tubercles, and metatarsal tubercle grey; ventral surface of inner two toes discs orange; iris distinctly bicolored, golden-yellow in upper one-fourth and reddish brown in lower three-fourths, black reticulations throughout.

Color of holotype in preservative.

For coloration of the holotype in preservative see Fig. 5A-D . After two years of storage in ethanol, the dorsal surface fading to metallic blue with irregular black spots; black crossbars present on dorsal surfaces of limbs, fingers and toes still clear; throat, chest, belly, and ventral surface of limbs fading to cream-yellow, with irregular gray pigmentations; ventral surface of the hands and toes cream-yellow, digit tips and subarticular tubercles fading to cream-yellow or grayish-white.

Male secondary sexual characteristics.

Adult males possess orange nuptial pads covering the base of first finger; absence of vocal sacs in males.

Distribution and ecology.

Amolops yangi sp. nov. is currently known from two localities in the Gaoligong Mountains. These are Fugong and Lushui County, both in Yunnan Province, China. These two localities are separated by a straight-line distance of approximately 80 km. The new species inhabits the banks of rocky, fast-flowing streams or perches on shrubs (ca. 0.5 m above the ground) along the swift flowing streams (Fig. 4F ). The new species primarily inhabits high altitude mountainous areas with elevations ranging from 2500 to 3500 m. The breeding season is currently uncertain. Other sympatric amphibian species found in the same habitat included Nanorana chayuensis , A. viridimaculatus , Scutiger gongshanensis , and Xenophrys glandulosa .

Comparisons.

Phylogenetic analyses indicated that the new species belongs to the A. viridimaculatus group with strong support. Geographically, the new species is found in Fugong and Lushui, Yunnan Province, China that belong to Gaoligong Mountains, and close to northern Myanmar. Therefore, we compared Amolops yangi sp. nov. with morphologically, geographically, and molecularly similar species, which include A. chayuensis , A. bellulus , A. putaoensis , A. binchachaensis , A. deng , A. jinjiangensis , A. viridimaculatus , A. kaulbacki , A. marmoratus , A. afghanus , and A. tuberodepressus , A. beibengensis , A. wangyufani , A. formosus , A. medogensis , A. pallasitatus , A. nidorbellus , A. himalayanus , A. wangyali , A. longimanus , A. ailao , A. chanakya , and A. tawang ( Andersson 1938; Jiang et al. 1983; Yang and Rao 2008; Fei et al. 2009; Biju et al. 2010; Dever et al. 2012; Sun et al. 2013; Nidup et al. 2016; Qi et al. 2019; Che et al. 2020; Gan et al. 2020; Liu and Yang 2000; Liu et al. 2000; Mahony et al. 2022; Rao et al. 2022; Saikia et al. 2022; Tang et al. 2023).

Amolops yangi sp. nov. is significantly different from A. viridimaculatus by discontinuous glandular dorsolateral fold (vs. absent), supratympanic fold indistinct (vs. distinct), SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. 72.7-82.3 in males and 83.0-94.3 in females), dorsal surface of the head, back, limbs, fingers, and toes green, interspersed with irregular black spots (vs. dorsum and flank with nearly round green or yellowish green spots, scattered with small green spots); from A. kaulbacki by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 72.6-82.6 mm in males and 82.7-87.2 mm in females), discontinuous glandular dorsolateral fold (vs. absent), supratympanic fold indistinct (vs. distinct), iris distinctly bicolored, golden-yellow in upper one-fourth and reddish brown in lower three-fourths, black reticulations throughout (vs. eyes brownish black with scattered yellow spotting and yellow ring around iris); from A. beibengensis by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 75.8 mm males and 90.2-93.2 mm in females), supratympanic fold indistinct (vs. distinct, wide and thick), discontinuous glandular dorsolateral fold from rear of eye to near vent (vs. absent); from A. wangyufani by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 68.3-69.0 mm males and 83.4 mm in female), vomerine teeth developed, on two short oblique between choanae, equal in distance from each other as to choanae (vs. vomerine teeth developed, the two rows are almost in touch), discontinuous glandular dorsolateral fold from rear of eye to near vent (vs. absent); from A. medogensis by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 95.0 mm male and 72.4-96.9 mm in females), tibiotarsal articulation of adpressed limb reaching between nostrils and eyes (vs. beyond tip of snout), supratympanic fold indistinct (vs. distinct, wide and thick); from A. himalayanus by dorsal surface of the head, back, limbs, fingers, and toes green, interspersed with irregular black spots (vs. dark brown, interspersed with irregular yellow spots), vocal sac absent in males (vs. externally visible vocal sacs present); from A. pallasitatus by SVL 51.5 mm in female (vs. SVL 70.6-72.3 mm in females), discontinuous glandular dorsolateral fold from rear of eye to near vent (vs. absent), dorsal surface of the head, back, limbs, fingers, and toes green, interspersed with irregular black spots (vs. dorsum yellow-green, with irregular dark brown blotches without margins); from A. wangyali by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 71.4-76.7 mm males and 80.5-89.6 mm in females), dorsal surface of the head, back, limbs, fingers, and toes green, interspersed with irregular black spots (vs. large brown irregularly shaped blotches on dorsum of head and body), rictal gland absent (vs. a distinct patch of rictal glands at rear of jaw on either side); from A. nidorbellus by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 76.4-82.3 mm males and 85.4-98.0 mm in females), dorsum green, interspersed with irregular black spots (vs. dorsally brown with small irregularly arranged cobalt green spots), discontinuous glandular dorsolateral fold (vs. absent); from A. longimanus by SVL 46.3-51.8 mm in males and 51.5 mm in female (vs. SVL 30 mm), nostrils closer to anterior corner of eye than to tip of snout (vs. nostrils a litter nearer to tip of snout than the eye), above tympanum to the forelimb a thick glandular parotoid-like swelling absent (vs. present), eye diameter (ED/SL 63.0%) shorter than snout length (vs. snout about as long as the eye diameter, ED/SL 97.7%); from A. formosus by dorsal parts of limbs, fingers and toes with black crossbars (vs. legs and toes with black white-dotted crossbars), inner metatarsal tubercle long, outer metatarsal tubercle absent (vs. metatarsal tubercle indistinct), dorsum green, interspersed with irregular black spots (vs. upper parts green, marbled with black, the black spots enclosing a number of small whitish dots); from A. chanakya by SVL 46.3-51.8 mm in males (vs. SVL 76.4 mm), tympanum indistinct (vs. tympanum distinct, about 40% of eye length), absence of vocal sacs in males (vs. vocal sac externally visible), dorsal color green, interspersed with irregular black spots (vs. dorsal color dull brick-red, spotted with irregular cocoa-brown spots, these cocoa-brown spots enclosing a number of smaller dull brick-red spots); from A. tawang by SVL 46.3-51.8 mm in males (vs. SVL 82.5 mm), tibiotarsal articulation of adpressed limb reaching between nostrils and eyes (vs. reaching up to snout), dorsal color green, interspersed with irregular black spots (vs. dorsal color olivegreen, spotted with large, irregular shaped dark-brown spots, brown spots enclosing a number of small olivegreen dots).

Amolops yangi sp. nov. is significantly different from A. chayuensis by absence of vocal sacs in males (vs. pair of external subgular vocal sacs); discontinuous glandular dorsolateral fold from rear of eye to near vent (vs. dorsolateral fold prominent); upper part of flanks green, lower part of flanks green-yellow (vs. upper part of flanks brown, lower part of flanks light green or white with dark brown blotches); from A. bellulus by tympanum indistinct (vs. tympanum distinct), iris distinctly bicolored, golden-yellow in upper one-fourth and reddish brown in lower three-fourths, black reticulations throughout (vs. upper half of iris golden yellow with some irregular brown spots, lower half dark brown); from A. putaoensis by SVL of adult male 46.3-51.8 mm (vs. 37.6-40.2 mm), rictal gland absent (vs. two rictal glands present), iris distinctly bicolored, golden-yellow in upper one-fourth and reddish brown in lower three-fourths, black reticulations throughout (vs. upper one-fourth of iris bronze with black reticulations, lower three-fourths dark), absence of vocal sacs in males (vs. pair of internal subgular vocal sacs present); from A. binchachaensis by SVL of adult female 51.5 mm (vs. 65.0 mm), tympanum indistinct, relatively small, about one third of eye diameter (vs. tympanum big), supratympanic fold indistinct (vs. supratympanic fold absent), dorsal surface of the head, back, limbs, fingers, and toes green (vs. light yellow); from A. deng by SVL of adult female 51.5 mm (vs. 68.5-72.0 mm), tympanum indistinct, relatively small, about one third of eye diameter (vs. tympanum distinct, slightly less than half of eye diameter), tibiotarsal articulation of adpressed limb reaching between nostrils and eyes (vs. tibiotarsal articulation of adpressed limb reaching beyond tip of snout); from A. jinjiangensis by supratympanic fold indistinct (vs. distinct), dorsal surface of head, body, limbs, fingers, toes and flank of body relatively smooth (vs. rough with tubercles), the absence of a pair of large tubercles on sides of cloaca (vs. present); from A. tuberodepressus by supratympanic fold indistinct (vs. present, wide), flanks smooth (vs. with flatter tubercles), relative length of fingers I<II<IV<III (vs. II<IV<I<III), vomerine teeth developed (vs. weak); from A. ailao by SVL 46.3-51.8 mm in males (vs. SVL 33.0-35.1 mm in males), vomerine teeth developed (vs. absent), tibiotarsal articulation of adpressed limb reaching between nostrils and eyes (vs. beyond anterior corner of eye), iris distinctly bicolored, golden-yellow in upper one-fourth and reddish brown in lower three-fourths (vs. iris light brown with dark wash); from A. marmoratus by tibiotarsal articulation of adpressed limb reaching between nostrils and eyes (vs. beyond tip of snout), discontinuous glandular dorsolateral fold from rear of eye to near vent (vs. distinct dorsolateral fold absent), rictal gland absent (vs. multiple small globular rictal glands on right side, single rictal gland on left side, just posterior to jaw); from A. afghanus by SVL 51.5 mm in female (vs. SVL 67.7-94.1 mm in females), rictal gland absent (vs. indistinct rictal glands present on one side of head at posterior end of jaw), absence of vocal sacs in males (vs. males with dual gular pouches).

Figures

Figure 4. Amolops yangi sp. nov. (Holotype KIZ 038643). A Lateral view, B dorsal view, C ventral view of thighs, D ventral view of hand, E foot, F habitat. Photos by Zhong-Bin Yu.

Figure 5. A Dorsal view, B ventral view, C ventral view of hand, D ventral view of foot, (D) Amolops yangi sp. nov. (Holotype KIZ 038643) in preservative. Photos by Zhong-Bin Yu.