Odorrana concelata Wang, Zeng, & Lin, 2022

Lin, Shi-Shi, Li, Yuan-Hang, Su, Hong-Lin, Yi, Hui, Pan, Zhong, Sun, Yan-Jun, Zeng, Zhao-Chi & Wang, Jian, 2022, Discovery of a new limestone karst-restricted odorous frog from northern Guangdong, China (Anura, Ranidae, Odorrana), ZooKeys 1120, pp. 47-66 : 47

Odorrana concelata Wang, Zeng, & Lin sp. nov.

Moss-speckled Odorous Frog (in English) / Tai Ban Chou Wa (苔斑臭蛙 in Chinese) Figs 3 , 4 , 5

Holotype.

GEP a055, adult male, collected by Shi-Shi Lin, Hong-Lin Su and Yuan-Hang Li on 20 April 2022 from Longlinchang Village (24°04'47"N, 112°40'37"E; ca. 280 m a.s.l.), Jintan Town, Qingyuan City, Guangdong, China.

Paratypes.

Three adult males, GEP a052-054, and two adult females, GEP a050-051, the same collection data as the holotype.

Etymology.

The specific epithet, Odorrana concelata , is a feminine adjective that means disguised, in reference to the highly concealed coloration of the new species in its mossy habitat.

Diagnosis.

(1) Small body size, SVL 34.0-36.8 mm in males (n = 4), SVL 41.4-46.0 mm in females (n = 2); (2) dorsolateral folds absent; (3) relative finger lengths II <I <IV <III; (4) pectoral spines absent; (5) vocal sacs absent; (6) nuptial pads present on base of finger I, medially along inner side of fingers II and III in males; (7) eggs of females uniformed beige; (8) dorsum with mixed irregular grass green speckles and brown mottling, ventral skin of body greyish white with light brown mottling.

Comparisons.

Odorrana concelata sp. nov. is phylogenetically closest to the clade composed of O. lipuensis and O. liboensis (Fig. 2 ). However, the new taxon can be distinguished by possessing a smaller body size, SVL 34.0-36.8 mm in males and 41.4-46.0 mm in females (vs. SVL 40.7-49.8 mm in males and 51.1-60.1 mm in females of O. lipuensis ; SVL 47.1-49.9 mm in males and 55.8-58.2 mm in females of O. liboensis ); presence of pineal body (vs. absent in O. lipuensis and O. liboensis ); presence of nuptial pads on base of finger I, medially along inner side of fingers II and III (vs. presence of nuptial pad on finger I in males of both O. lipuensis and O. liboensis ); relative finger lengths II <I <IV <III (vs. I = II <IV <III in O. lipuensis ); absence of conical spines on upper lip except skin of commissure of jaw (vs. presence of conical spines on entire upper lip in O. lipuensis ); tibiotarsal articulation reaches to nostril (vs. reaches to anterior of eye in O. lipuensis ); presence of tiny conical spines on temporal region except tympanum, skin of commissure of jaw, upper edge of eyelid, and along dorsolateral sides of body (vs. absent in O. liboensis ). Odorrana concelata sp. nov. further differs from another karst-dweller O. wuchuanensis by the smaller body size (vs. 71.1-76.5 mm in males and 75.8-99.6 mm in females), and absence pectoral spines (vs. present).

Odorrana concelata sp. nov. can be easily distinguished from O. absita , O. amamiensis , O. anlungensis , O. aureola , O. bacboensis , O. banaorum , O. bolavensis , O. cangyuanensis , O. chapaensis , O. chloronota , O. dulongensis , O. exiliversabilis , O. fengkaiensis , O. geminata , O. gigatympana , O. grahami , O. graminea , O. hainanensis , O. hejiangensis , O. huanggangensis , O. indeprensa , O. ichangensis , O. ishikawae , O. jingdongensis , O. junlianensis , O. khalam , O. kweichowensis , O. lungshengensis , O. macrotympana , O. morafkai , O. nanjiangensis , O. nasica , O. nasuta , O. orba , O. sangzhiensis , O. schmackeri , O. swinhoana , O. tianmuii , O. tiannanensis , O. tormota , O. trankieni , O. utsunomiyaorum , O. versabilis , O. yentuensis , O. yizhangensis and O. yunnanensis , by the absence of vocal sacs (vs. present; internal vocal sacs present in O. grahami , O. hainanensis , O. jingdongensis , O. junlianensis , O. yunnanensis ); and from O. absita , O. amamiensis , O. banaorum , O. bolavensis , O. exiliversabilis , O. gigatympana , O. graminea , O. indeprensa , O. hosii , O. khalam , O. livida , O. leporipes , O. monjerai , O. narina , O. nasica , O. nasuta , O. orba , O. supranarina , O. tormota , O. trankieni , O. utsunomiyaorum , O. versabilis , and O. yentuensis , by the absence of dorsolateral folds (vs. present).

Odorrana concelata sp. nov. differs from the remaining seven congeners by the marked differences in dorsal and ventral coloration; the smaller body size, SVL 34.0-36.8 mm in males and 41.4-46.0 mm in females (vs. 57.2 mm in male and 66.0-71.4 mm in females in O. kuangwuensis , 78.0-88.0 mm in males and 93.0-113.0 mm in females in O. margaretae , 85.8-91.6 mm in males and 108.7-110.1 mm in females in O. mutschmanni , 80.0 mm in males and 84.3-106.0 mm in females in O. mawphlangensis , 44.0-55.0 mm in males and 86.0-97.0 mm in females in O. rotodora , 66.6 mm in male in O. sinica , and 74.4-124.4 mm in males and 94.6-137.4 mm in females in O. splendida ).

Description of holotype.

Adult male. Body slender and small, SVL 36.8 mm. Head length larger than head width, HDW/HDL ratio 0.88; snout short, rounded in dorsal view, projecting beyond lower jaw, snout length larger than eye diameter, SNT/ED ratio 1.35; canthus rostralis distinct; nostril rounded, located laterally, closer to tip of snout than eye; internasal distance larger than interorbital distance, IND/IOD ratio 1.09; loreal region slightly concave and oblique; eye large and prominent; tympanum rounded, large, TD/ED ratio 0.86, edge of tympanum slightly elevated relative to tympanum; strong vomerine ridges bearing vomerine teeth; tongue deeply notched distally; pupil horizontally oval; pineal body present, small; vocal sac absent.

Forelimbs slender, HND/SVL ratio 0.28, RAD/SVL ratio 0.22; fingers slender, relative finger lengths II <I <IV <III; tips of fingers expanded into disc, all with circummarginal grooves, horizontal grooves present, without webbing and lateral fringes; subarticular tubercles prominent: 1, 1, 2, 2; inner metacarpal tubercle oval, elongate; medium and outer metacarpal tubercles oval; nuptial pads present on base of finger I, medially along inner side of fingers II and III.

Hindlimbs slender, FTL/SVL ratio 0.70, TIB/SVL ratio 0.50; heels overlapping when thighs are appressed at right angles with respect to body; tibiotarsal articulation reaches to nostril when leg stretched forward; relative toe lengths I <II <III <V <IV; toes entirely webbed; tips of toes expanded into disc with circummarginal grooves; subarticular tubercles prominent: 1, 1, 2, 3, 2; inner metatarsal tubercle oval, elongate, almost equal length to first toe; outer metatarsal tubercle absent.

Dorsal skin relatively smooth, granular; skin of loreal region smooth; weak supratympanic fold from posterior corner of eye to posterior edge of tympanum; dorsolateral folds absent; tiny conical spines present on temporal region except tympanum, skin of commissure of jaw, upper edge of eyelid, and along dorsolateral sides of body. Ventral skin smooth.

Coloration of holotype in life.

Skin of dorsal body, dorsal limbs and flanks with irregular moss-green speckles and brown mottling; dorsal skin of limbs with distinct brown transverse bands; ventral skin of body greyish white with light brown mottling; ventral skin of forelimb greyish white, ventral skin of hindlimb purplish brown. Iris black, with irregular gold-green reticulated mottles; pineal body light green; tympanum dark brown; nuptial pad creamy white.

Coloration of holotype in preservative.

Skin of dorsal body, dorsal limbs and flanks greyish brown, with brown mottling and dark brown transverse bands, moss-green speckles absent; ventral skin of body greyish white with brown mottling; ventral skin of thighs greyish white, ventral skin of shank and foot dark grey with dark brown mottling.

Variations.

Mensural data of the type series are listed in Table 3 . Most of the paratypes are similar to the holotype in morphology and color pattern, except for the following: (1) skin of dorsal trunk lacking tiny spines (vs. present in the male paratype GEP a052); (2) sparse spines on temporal region except tympanum, skin of commissure of jaw, upper edge of eyelid, and along dorsolateral sides of body; nuptial pads absent; and larger body size in female paratypes (Fig. 4 ).

Distribution and habits.

Currently, Odorrana concelata sp. nov. is known only from its type locality (Fig. 1 , solid circle). The nocturnal karst-dweller inhabits mossy rocks and damp forest floors in subtropical evergreen broad-leaved forests and secondary forests at elevations between 200-300 m (Fig. 5A, B ). They are completely hidden in their habitat by their coloration (Fig. 5D, E ). During breeding season (March to June), they congregate in and around the small and steep moss-covered waterfalls which flows out of karst caves (ca. 1-2 m width). Juveniles were observed in June (Fig. 5C ). No individuals were found during surveys in mid-July.

Figures

Figure 1. Distribution of Odorrana concelata sp. nov. (solid circle), O. lipuensis (solid squares), and O. liboensis (solid triangle).

Figure 2. Maximum-likelihood and Bayesian inference phylogenies. Numbers at nodes indicate the bootstrap support (BS) / Bayesian posterior (BPP) for the topology. ' - ' means BS <70 or BPP <0.90.

Figure 3. Morphological features of the male holotype GEP a 055 in life: A dorsolateral view B ventral view C ventral view of hand, showing nuptial pads on fingers I, II and III D ventral view of foot.

Figure 4. Morphological features of the female paratype GEP a 050 in life: A dorsolateral view B ventral view C ventral view of hand D ventral view of foot.

Figure 5. Microhabitat of Odorrana concelata sp. nov. (A, B) and the uncaptured individuals of juvenile (C), female (D), and male (E) in situ.