Leptobrachella wuhuangmontis Wang, Yang & Wang

Wang, Jian, Yang, Jianhuan, Li, Yao, Lyu, Zhitong, Zeng, Zhaochi, Liu, Zuyao, Ye, Youhua & Wang, Yingyong, 2018, Morphology and molecular genetics reveal two new Leptobrachella species in southern China (Anura, Megophryidae), ZooKeys 776, pp. 71-103 : 71

Leptobrachella wuhuangmontis Wang, Yang & Wang sp. n. Figures 6, 7

Holotype.

SYS a003486, adult male, collected on 29 March 2015 by JW, ZTL, YYW and ZYL from Mt. Wuhuang (MWH hereafter) (22°08'30.77"N, 109°24'43.90"E; 500 m a.s.l.), Pubei County, Qinzhou City, Guangxi Province, China.

Paratypes.

Adult males SYS a000578, 581 and an adult female SYS a000580, collected on 28 April 2009 by Jian-Huan Yang (JHY hereafter) and Run-Lin Li (RLL hereafter), adult males SYS a003487-3489, 3505-3506, SYS a003500 / CIB107274 and adult females SYS a003485, 3499, 3504,, collected from 29-30 March 2015 by JW, ZTL, YYW and ZYL, all from the same locality as the holotype.

Diagnosis.

(1) small size (SVL 25.6-30.0 mm in males, 33.0-36.0 mm in females), (2) dorsal surface rough with skin ridges and dense conical tubercles, (3) iris bicolored, coppery yellow on upper half and silver on lower half, (4) tympanum distinctly discernible, slightly concave, dark brown, distinct black supratympanic line present, (5) dorsal surface greyish purple background with dark brown markings and scattered with orange-yellow blotches and white speckling, (6) distinct dark blotches on flanks, (7) ventral surface greyish white mixed by tiny white and black dots, (8) lateral fringes on fingers absent, (9) toes with narrow lateral fringes and rudimentary webbing, (10) longitudinal ridges under toes not interrupted at the articulations, and (11) dense conical spines on lateral and ventral surface of tarsus, dorsal surface of tibia-tarsal and surface of inner-side shank and surface around cloacal region.

Comparisons.

Comparative morphological data of Leptobrachella wuhuangmontis sp. n. with the 66 recognized Leptobrachella species were obtained from examination of museum specimens (see Appendix 1) and from the references listed in Table 2. All comparative data were shown in Tables 4, 5, 6.

Compared with the 24 known congeners of the genus Leptobrachella occurring south of the Isthmus of Kra, by the presence of supra-axillary and ventrolateral glands, L. wuhuangmontis sp. n. can be easily distinguished from L. arayai , L. dringi , L. fritinniens , L. gracilis , L. hamidi , L. heteropus , L. kajangensis , L. kecil , L. marmorata , L. melanoleuca , L. maura , L. picta , L. platycephala , L. sabahmontana , and L. sola , all of which lacking supra-axillary and ventrolateral glands; and by the significantly larger body size, SVL 25.6-30.0 mm in males, 33.0-36.0 mm in females, L. wuhuangmontis sp. n. differs from the smaller L. baluensis (14.9-15.9 mm in males), L. brevicrus (17.1-17.8 mm in males), L. itiokai (15.2-16.7 mm in males), L. juliandringi (17.0-17.2 mm in males and 18.9-19.1 mm in females), L. mjobergi (15.7-19.0 mm in males), L. natunae (17.6 mm in male), L. parva (15.0-16.9 mm in males and 17.8 mm in female), L. palmata (14.4-16.8 mm in males), L. serasanae (16.9 mm in female) and Dring’s (1983) Leptobrachella sp. 3 “baluensis” (15.0-16.0 mm in males).

Leptobrachella wuhuangmontis sp. n. significantly differs from L. yunkaiensns sp. n. by a large genetic divergence (p=10.2-11.1%), lateral fringes on toes narrow (vs. wide), black supratympanic line distinct (vs. weak), dorsal surface of body rough and scattered with dense conical tubercles (vs. shagreened with short skin ridges and raised warts), belly greyish white mixed by tiny white and black dots (vs. belly pink with distinct or indistinct speckling).

From the rest 42 known congeners (Table 5), with SVL 25.6-30.0 mm in nine males and 33.0-36.0 mm in four females, Leptobrachella wuhuangmontis sp. n. differs from the larger L. bourreti (females 42.0-45.0 mm), L. eos (males 33.1-34.7 mm, female 40.7 mm), L. lateralis (female 36.6 mm), L. nahangensis (male 40.8 mm), L. nyx (females 37.0-41.0 mm), L. sungi (males 48.3-52.7 mm, females 56.7-58.9 mm), L. tamdil (male 32.3 mm) and L. zhangyapingi (males 45.8-52.5 mm); and from the smaller L. aerea (females 28.8-28.9 mm), L. ardens (female 24.5 mm), L. alpinus (females 32.1-32.5 mm in), L. applebyi (males 19.6-20.8 mm, female 21.7 mm), L. bidoupensis (males 18.5-25.4 mm), L. botsfordi (females 30.0-31.8 mm), L. kalonensis (females 28.9-30.6 mm), L. laui (female 28.1 mm), L. liui (females 23.0-28.0 mm), L. maculosa (female 27.0 mm), L. maoershanensis (female 29.1 mm), L. melica (males 19.5-22.7 mm), L. oshanensis (female 31.6 mm), L. pluvialis (males 21.0-22.0 mm), L. puhoatensis (females 27.3-31.5 mm), L. rowleyae (females 27.0-27.8 mm), L. tadungensis (female 32.1 mm), and L. tengchongensis (females 28.9-28.9 mm). Having head longer than wide in the new species (vs. head wider than long in L. bourreti , L. khasiorum , L. lateralis and L. sungi , and head width equal to or wider than long in L. nokrekensis ). By having narrow fringes on toes, the new species differs from L. applebyi , L. ardens , L. crocea , L. kalonensis , L. lateralis , L. maculosa , L. macrops , L. melica , L. minima , L. nahangensis , L. nyx , L. oshanensis , L. pallida , L. pluvialis , L. pyrrhops , L. rowleyae , L. tadungensis , L. tuberosa , and L. ventripunctata , all of which have no lateral fringes on toes; L. bidoupensis , L. bourreti , L. fuliginosa , and L. sungi , all of which have weak lateral fringes on toes; L. alpinus , L. firthi and L. isos , all of which have wide lateral fringes only in males; L. aerea , L. eos , L. khasiorum , L. laui , L. liui , L. purpura , L. tamdil , L. yingjiangensis , and L. zhangyaping , all of which have wide lateral fringes both in males and females. By having rudimentary webbing on toes, the new species differs from L. ardens , L. kalonensis , L. maculosa , L. oshanensis , L. pallida , L. petrops , L. rowleyae , and L. tadungensis , all of which have no webbing on toes; L. pelodytoides , L. sungi , and L. tamdil , all of which have wide webbing on toes. By having black spots on flanks, the new species differs from L. aerea , L. botsfordi , L. eos , L. firthi , L. isos , L. pallida , L. petrops , L. tuberosa , and L. zhangyapingi , all of which have no black spots on flanks. By having rough dorsal skin with skin ridges and dense conical tubercles, the new species differs from L. applebyi , L. bidoupensis , L. kalonensis , L. melica , L. minima , L. nahangensis , and L. tadumgensis , all of which have smooth dorsal skin, and from L. purpura , L. tengchongensis , and L. yingjiangensis , all of which have shagreened dorsal skin with small tubercles.

Description of holotype.

Adult male. Body size small, SVL in 30.0 mm. Head slightly longer than wide, HDL/HDW 1.04; snout rounded in dorsal view, nostril rounded, closer to tip of snout than to eye; canthus rostralis distinct; lores slightly concave; eye large, diameter equal to snout length, in 4.3 mm; tympanum distinct, rounded and slightly concave, its diameter significantly shorter than eye, TMP/EYE 0.56; distinct black supratympanic line present; vomerine teeth absent; vocal sac opening slit-like; tongue deeply notched behind; supratympanic ridge distinct, running from eye towards supra-axillary gland with raised tubercles.

Tips of fingers rounded, slightly swollen; relative finger lengths I = II <IV <III; nuptial pad absent; subarticular tubercles absent; a large, rounded inner palmar tubercle distinctly separated from small, round outer palmar tubercle; finger webbing absent and lateral fringes absent. Tips of toes like fingers; relative toe length I <II <V <III <IV; subarticular tubercles absent; dermal ridges undeveloped but present under the 3rd to 5th toes; large, oval inner metatarsal tubercle present, outer metatarsal tubercle absent; toes webbing rudimentary; narrow lateral fringes present on all toes. Tibia 45% of snout-vent length; tibiotarsal articulation reaches to middle of eye; heels just meeting each other when thighs are appressed at right angles with respect to body.

Skin on dorsum body and limbs rough with skin ridges and dense conical tubercles, ventral skin smooth; pectoral gland and femoral gland large, oval, slightly elevated; femoral gland situated on posterovertral surface of thigh, closer to knee than to vent; supra-axillary gland raised. Ventrolateral gland distinct, forming an incomplete line. Dense conical spines present on surface of lateral and ventral tarsus, surface of tibia-tarsal, inner-side surface of shank and surface around cloacal region.

Measurements of holotype

(in mm).SVL 30.0, HDL 10.9, HDW 10.5, SNT 4.3, EYE 4.3, IOD 2.9, IND 3.0, TMP 2.4, TEY 0.8, TIB 13.5, ML 7.8, PL 13.0, LAHL 15.4, HLL 44.9.

Coloration of holotype in life.

Dorsal surface greyish purple with distinct dark brown markings and scattered with yellow blotches; distinct small white speckling present on edges of dark markings. A distinct dark brown triangle pattern between eyes, connected to the incomplete W-shaped dark brown marking between axillae. Tubercles on dorsum of body and limbs brown, those on lower flanks somewhat whitish; anterior upper lip with distinct blackish brown patches; transverse dark brown bars on dorsal surface of limbs; distinct dark brown blotches on flanks from groin to axilla; elbow and upper arms coppery orange and with distinct dark bars; fingers and toes with distinct dark brown blotches.

Ventral surface greyish-white mixed with tiny white and black dots. Supra-axillary, femoral, and ventrolateral glands white, pectoral gland greyish white as the color of ventral surface. Iris bicolored, coppery yellow on upper half and silver on lower half.

Coloration of holotype in preservative.

Dorsal of body dark with greyish white dots on flanks, while dorsal of limbs dark brown, transverse bars on dorsal of forelimbs become more distinct, and indistinct on dorsal of hindlimbs, dark brown patterns, markings and spots on back become indistinct. Ventral surface light yellow with brown speckling. Supra-axillary, femoral, ventrolateral and pectoral glands light yellow (Figure 7).

Sexual dimorphism.

Females with a larger body size than males, SVL 33.0-36.0 mm (34.9 ± 1.4) (vs. SVL 25.6-30.0 mm (28.5 ± 1.5) in males); presence of a single vocal sac in males (vs. absent in females); dense conical spines on lateral and ventral surface of tarsus, surface of tibia-tarsal, inner-side surface of shank and surface around cloacal region distinct in males (vs. barely visible in females); pectoral gland and femoral gland large, oval, slightly elevated in males (vs. indistinct in females).

Variations.

All paratypes match the overall characters of the holotype except that: tibiotarsal articulation reaches to posterior corner of eye in female paratypes SYS a003499, 3504 and reaches to anterior corner of eye in male paratypes SYS a003487 and SYSa 003500 / CIB 107274; pectoral gland large, oval, slightly elevated in all individuals in life, and become indistinct in preservation. Yellow blotches and white speckling present on dorsum in the holotype (vs. indistinct in the female paratype SYS a003499). Elbow and upper arms coppery orange and with distinct dark bars in the holotype (vs. elbow and upper arms light orange, dark bars indistinct in the male paratypes SYS a003488, 3505 and the female paratype SYS a003499) (Figure 6).

Etymology.

The specific epithet, wuhuangmontis , is in reference to the type locality, Mt. Wuhuang of Guangxi Province, China. For the common name, we suggest "Mt. Wuhuang’s Leaf Litter Toad", and for the Chinese name "Wu Huang Shan Zhang Tu Chan ( 五皇山掌突蟾)”.

Distribution and habits.

Currently, Leptobrachella wuhuangmontis sp. n. is only known from its type locality MWH from Guangxi Province of China (Figure 1). The new species was found along a clear-water rocky streams and small steep rocky streams in well-preserved montane evergreen broadleaf forest (500 m a.s.l.) (Figure 8). During field surveys in March, males were found calling exposed on the rocks or hiding in the rock seams; gravid female collected on March and April bear pure white oocytes.