Amolops teochew, Zeng & Wang & Lyu & Wang, 2021

Zeng, Zhao-Chi, Wang, Jian, Lyu, Zhi-Tong & Wang, Ying-Yong, 2021, A new species of Torrent frog (Anura, Ranidae, Amolops) from the Coastal Hills of Southeastern China, Zootaxa 5004 (1), pp. 151-166 : 156-161

Amolops teochew sp. nov.

Chresonymy.

Amolops daiyunensis — Fei et al. 2009 (Fujian: Nanjing, Yongding, and Zhao’an)

Amolops hongkongensis — Li et al. 2011 (Guangdong: Nan’ao); Zeng et al. 2020 (Guangdong: Jiexi, Fengshun, and Pu’ning)

Holotype. SYS a008705 ( Figs. 3 , 4 ), adult female, collected by Zhi-Tong Lyu, Zhao-Chi Zeng, and Shuo Qi on 11 April 2021 from Mt Fenghuang (23.8506°N, 116.7429°E; ca 890 m a.s.l.), Chao’an District, Chaozhou City, Guangdong Province, PR China.

Paratypes. Thirteen adult female specimens: CIB 116082 (field number SYS a003693) collected by Jian Wang on 2 May 2015 from Mt Fenghuang; SYS a006081–6083, 6088 collected by Jian Wang and Hui-Wen Xiao on 25–26 July 2017 from Mt Dabei (23.5429°N, 115.9201°E; ca 720 m a.s.l.), Jiexi County, Jieyang City , Guangdong; SYS a007584 collected by Jian Wang and Hong-Hui Chen on 5 January 2019 from Mt Liwangzhang (23.6355°N, 115.8217°E; ca 980 m a.s.l.), Jiexi ; SYS a004740–4741, 4747–4748 collected by Jian Wang and Zhi-Tong Lyu on 12–14 May 2016 from Mt Tongguzhang (24.1682°N, 116.3441°E; ca 940 m a.s.l.), Fengshun County , Meizhou City , Guangdong; SYS a005217 collected by Jian Wang and Chun-Peng Guo on 8 August 2016 from Mt Tongguzhang ; SYS a005536 collected by Jian Wang on 6 October 2016 from Mt Da’nan (23.2538°N, 116.1497°E; ca 380 m a.s.l.), Pu’ning City , Jieyang ; SYS a006774 collected by Jian Wang, Can-Rong Lin , and Hui-Wen Xiao on 24 Feburary 2018 from Mt Emeizhang (23.1661°N, 115.7671°E; ca 760 m a.s.l.), Pu’ning .

Other examined material. Four adult female specimens: SYS a003339 collected by Zhi-Tong Lyu and Zu- Yao Liu on 22 September 2014 from Huboliao Nature Reserve (24.5914°N, 117.1100°E; ca 700 m a.s.l.), Nanjing County, Zhangzhou City, Fujian Province, China ; SYS a006018 collected by Jian Wang and Zhi-Tong Lyu on 29 June 2017 from Huboliao Nature Reserve ; SYS a004099, 4108 collected by Jian Wang and Zhi-Tong Lyu on 15 July 2015 from Gutian Town (25.2203°N, 116.8434°E; ca 790 m a.s.l.), Shanghang County, Longyan City, Fujian .

Etymology. The specific name teochew is a noun referring to “Teochew Fu (潮州府)”, a historic prefecture encompassing “Teochew Poit Ip (潮州八ǟ)” but currently split into Chaozhou, Shantou, and Jieyang cities, and Fengshun County in eastern Guangdong. The first three authors of this work were born in Jieyang and Chaozhou respectively, and would like to denominate this new species in honor of our hometown.

Common name. “Teochew Torrent Frog” in English and “潮州flḃ (chao zhou tuan wa)” in Chinese.

Diagnosis. The diagnostic character for the genus Amolops is the presence of an abdominal sucker in the tadpole and the absence of scattered glands on the back of the tadpole ( Yang 1991). However, because the tadpole of the new species remains to be discovered, we assigned the new species to this genus and further to the A. daiyunensis group based upon the morphological and genetic similarity of the adult specimens to those of A. daiyunensis and A. hongkongensis .

Amolops teochew sp. nov. is distinguished from its congeners by a combination of the following morphological characteristics: (1) body stout and robust, slightly flattened, SVL 43.4–49.9 mm (46.9 ± 1.9 mm, n = 14) in adult females; (2) dorsal coloration of body brown, with light yellow marbled patterns on the dorsum and head, and distinct light-colored crossbars on the hindlimbs and upper forelimbs; (3) dorsal and ventral surface smooth; skin slightly wrinkled with several small light-colored tubercles on the flank and posterior of limbs, not bearing horny spinules throughout the skin; (4) pineal ocellus present, occipital region with faint protuberance; (5) vomerine teeth absent, tongue slightly notched posteriorly; (6) tympanic edge unclear, upper margin concealed by the supratympanic fold; (7) supratympanic fold distinct, dorsolateral fold absent; (8) the circummarginal groove on the disk of finger I present; (9) subarticular tubercles present only at the base of each finger, supernumerary tubercle present only below the base of finger III, inner metacarpal tubercle unclear and the outer metacarpal tubercle absent; (10) heels meeting when adpressed, tibio-tarsal articulation reaching between the snout and the anterior corner of the eye; (11) metatarsal tubercles absent, tarsal glands and tarsal fold present.

Description of holotype. SYS a008705 ( Figs. 3 , 4 ), adult female. Body stout and robust, slightly flattened, SVL 43.4 mm. Head width equal to length (HDW/HDL = 1.00); snout short (SNT/HDL = 0.36), rounded in profile, projecting beyond lower jaw; nostril closer to tip of snout than eye; loreal region concave; top of head flat, pineal ocellus present, the occipital region with faint protuberance; eye large (ED/HDL = 0.37), convex; canthus rostralis distinct; pineal body distinct; tympanic edge unclear, upper margin concealed by the supratympanic fold; choanae moderate; vomerine teeth absent; tongue cordiform, slightly notched posteriorly.

Forelimbs relatively slender, moderately long (RAD/SVL = 0.18, HND/SVL = 0.29); relative finger lengths I <II <IV <III; tips of all finger dilated into wide oval discs with circummarginal grooves, relative width of finger discs I <II <IV = III; fingers unwebbed, narrow lateral fringes only present on fingers III and IV; subarticular tubercles present only at base of each finger, prominent, rounded; supernumerary tubercle present only below base of finger III, distinct and prominent; inner metacarpal tubercle indistinct, outer metacarpal tubercle absent.

Hindlimbs moderately robust, long (TIB/SVL = 0.53, FTL/SVL = 0.71); tibio-tarsal articulation reaching anterior corner of eye when hindlimb adpressed alongside the body; heels meeting when hindlimbs flexed at right angles to axis of body; relative toe lengths I <II <III <V <IV; tips of all toes expanded into well-developed oval discs with circummarginal grooves; subarticular tubercles oval, distinct, formula 1, 1, 2, 3, 2; metatarsal tubercles absent; toes fully webbed, webbing formula I 1–1 II 1–1 III 1–1⅓ IV 1⅓–1 V; lateral fringes of toes I and V narrow; tarsal glands present but undeveloped, tarsal fold present.

Dorsal skin of body smooth, slightly wrinkled, several small tubercles on flank and posterior of limbs; supratympanic fold distinct, running from posterior corner of upper eyelid to shoulder; dorsolateral folds absent; upper lip slightly swollen. Ventral skin smooth, slightly wrinkled, small tubercles on posterior of limbs and near cloaca.

Coloration of holotype. In life ( Fig. 3 ), the dorsal coloration of body is olive-brown, with light yellow marbled patterns on dorsum and head; pineal ocellus is yellowish; tubercles on the flank are yellow or white, and those on the posterior of limbs are white; distinct light-colored crossbars present on the dorsal surfaces of hindlimbs and upper forelimbs; and dorsal coloration of discs of digits are yellowish or white. Throat, chest, and abdomen are creamy white; ventral surfaces of limbs, hands, and feet are purplish-grey, and the posterior of thighs are mottled with dark spots; subarticular tubercles and supernumerary tubercle on digits are greyish; and tarsal glands are greyish.

In preservative ( Fig. 4 ), dorsal surfaces turned darker, while spots and patches on dorsum, flanks, and head were faded but more distinct, and crossbars on limbs were more distinct. Ventral surface was creamy white, ventral surface of limbs were greyish, subarticular tubercles and supernumerary tubercle became more distinct, and tarsal glands faded to off-white or light-grey.

Variations. Measurements of type series specimens are given in Table 3. Due to the lack of male specimens, it is unclear about the sexual dimorphism in this species, and the male secondary sexual characteristics remain unknown as well.

All female specimens are very similar in morphology. The dorsal coloration varies from olive-brown, yellowish-brown, to reddish-brown; and the degree of patterning on the dorsal surface varies among individuals but is always marbled ( Figs. 5 , 6A, B ). When the hindlimb is stretched and adpressed alongside the body, tibio-tarsal articulations reach between the snout and the anterior corner of the eye. Greyish spots are present on the throat and chest in SYS a004740 ( Fig. 5A ); and pineal ocellus is indistinct in SYS a006088 ( Fig. 5B ).

Distribution and ecology. Currently, Amolops teochew sp. nov. is known from multiple localities in the coastal hill region of eastern Guangdong and southern Fujian provinces, China. All individuals were observed in fast-flowing streams, especially near steep waterfalls, surrounded by moist, secondary, subtropical evergreen broadleaved forests ( Fig. 6 ). Despite the relatively wide distribution of Amolops teochew sp. nov., most of its localities are being threatened by the developments brought about by tourism and tea planting, and only a few nature reserves cover the habitats of this frog.

During our repeated surveys throughout its distribution in different months, only females of Amolops teochew sp. nov. were found, and the information for males, tadpoles, and more ecological data remain unknown. Females possess small, creamy white, undeveloped eggs in their ovaries in mid-April (specimen SYS a008705), May (CIB 116082, SYS a004740–4741, 4747–4748), and early October (SYS a005536), and possess large, creamy yellow, developed eggs in the fallopian tubes from late July (SYS a006081–6083, 6088) to early August (SYS a005217), suggesting its breeding season might be during this period.

Comparisons. Due to the strongly supported phylogenetic placement and distribution of Amolops teochew sp. nov., the new species is compared in detail with the congeners of the A. daiyunensis group, A. ricketti group, and A. hainanensis group only.

Within the Amolops daiyunensis group, Amolops teochew sp. nov. ( Fig. 7A ) differs from A. daiyunensis ( Fig. 7B ) by having a smooth dorsal surface and lacking spinules (vs. rough with dense spinules), faint protuberance on occipital region (vs. remarkably swollen protuberance), unclear tympanic edge (vs. distinct), distinct subarticular tubercles on fingers (vs. undeveloped), and the presence of pineal ocellus (vs. absence) and the presence of tarsal folds (vs. absence). Amolops teochew sp. nov. is the sister taxon of A. hongkongensis , and differs from A. hongkongensis ( Fig. 7C, D ) by having a smooth dorsal surface (vs. rough with dense tubercles on dorsum, flanks, head, and limbs), distinct dorsal patterning (marbled with large, lightly colored blotches vs. densely speckled), distinct crossbars on the limbs with clear edges (vs. visible but with faint and unclear edges), distinct supratympanic fold (vs. indistinct), faint protuberance on occipital region (vs. remarkably swollen protuberance), supernumerary tubercle present only below the base of finger III (vs. supernumerary tubercles present below the bases of fingers II, III and IV), and the presence of pineal ocellus (vs. absence); and the absence of outer metacarpal tubercle (vs. distinct and fleshy).

Amolops teochew sp. nov. is sympatric with A. albispinus Sung, Wang, and Wang, 2016 ( Fig. 7E ) in Mt Dabei (locality 2 in Fig. 1 ), but can be distinguished by the presence of tarsal glands and tarsal folds (vs. absence of both in A. albispinus ), and dorsal skin texture (smooth without spinules vs. rough with dense spinules on dorsum and head). Amolops teochew sp. nov. can be further distinguished from the remaining five species of the A. ricketti group [ A. ricketti ( Boulenger, 1899) , A. sinensis Lyu, Wang & Wang, 2019 , A. wuyiensis ( Liu & Hu, 1975) , A. yatseni Lyu, Wang & Wang, 2019 , and A. yunkaiensis Lyu, Wang, Liu, Zeng & Wang, 2018 ] by the presence of tarsal glands and tarsal folds (vs. absence of both).

Compared to the two species of the Amolops hainanensis group, Amolops teochew sp. nov. differs from A. hainanensis ( Boulenger, 1900) by having a relatively smaller body size (SVL <50 mm in adult females vs. SVL> 65 mm), unclear tympanum edge (vs. distinct), faint protuberance on occipital region (vs. distinct protuberance), and smooth dorsal surface (vs. rough with dense tubercles on dorsum, flanks, and head); differs from A. torrentis ( Smith, 1923) by having a relatively larger body size (SVL> 43 mm in adult females vs. SVL <42 mm), unclear tympanum edge (vs. distinct), and tibio-tarsal articulation reaching between the snout and the anterior corner of the eye when hindlimb adpressed (vs. beyond the snout).

Figures

FIGURE 1. Localities of specimens and tissue samples used in this study. Localities for Amolops teochew sp. nov.: (1) Mt Fenghuang, Chao’an, Chaozhou; (2) Mt Dabei, Jiexi, Jieyang; (3) Mt Liwangzhang, Jiexi, Jieyang; (4) Mt Tongguzhang, Fengshun, Meizhou; (5) Mt Da’nan, Pu’ning, Jieyang; (6) Mt Emeizhang, Pu’ning, Jieyang; (7) Nan’ao Island, Nan’ao, Shantou; (8) Huboliao Nature Reserve, Nanjing, Zhangzhou; (9) Gutian Town, Shanghang, Longyan; (10) Tingxi, Tong’an, Xiamen. Information for other localities given in Table 1. Half icon indicates the sympatric distribution with other species.

FIGURE 3. The adult female holotype SYS a008705 of Amolops teochew sp. nov. in life. (A) dorsolateral view; (B) ventral view; (C) right hand; (D) left foot.

FIGURE 4. The adult female holotype SYS a008705 of Amolops teochew sp. nov. in preservative. (A) dorsal view; (B) ventral view; (C) lateral view; (D) right hand; (E) left foot.

FIGURE 5. The colorations of Amolops teochew sp. nov. in life. (A) dorsolateral and ventral views of paratype SYS a004740; (B) dorsolateral view and a close-up of the head of paratype SYS a006088.

FIGURE 6. (A) an uncaptured individual of Amolops teochew sp. nov. at a cliff near a steep waterfall in Mt Tongguzhang, Fengshun; (B) an uncaptured individual in a fast-flowing stream in Gutian Town, Shanghang; (C) and (D) the habitats in Mt Fenghuang, Chao’an.

FIGURE 7. Comparisons among Amolops teochew sp. nov., congeners in the A. daiyunensis group, and the sympatric A. albispinus. (A) holotype of Amolops teochew sp. nov.; (B) topotype of A. daiyunensis from Mt Daiyun, Fujian; (C) topotype of A. hongkongensis from Tai Mo Shan, Hong Kong; (D) A. hongkongensis from Gutian Nature Reserve, Guangdong; (E) A. albispinus from Mt Dabei, Guangdong; (1) dorsolateral view; (2) ventral hand; (3) ventral foot.