Rana (Rana) jiulingensis Wan, Lyu & Wang, 2020

Wan, Han, Lyu *, Zhi-Tong, Qi, Shuo, Zhao, Jian, Li, Pi-Peng & Wang, Ying-Yong, 2020, A new species of the Rana japonica group (Anura, Ranidae, Rana) from China, with a taxonomic proposal for the R. johnsi group, ZooKeys 942, pp. 141-158 : 141

Rana (Rana) jiulingensis Wan, Lyu & Wang sp. nov.

Holotype.

SYS a005519 (Fig. 3 ), adult male, collected by Zhi-Tong Lyu, Jian Wang and Hai-Long He on 14 September 2016 from Guanshan Nature Reserve (28.5535N, 114.5878E; ca 300 m a.s.l.), Yifeng County, Jiangxi province, PR China.

Paratypes.

Seven adult specimens. Females SYS a002584-2585 collected by Jian Zhao on 8 May 2014 from Mt Wugong (27.4607N, 114.2059E; ca 1100 m a.s.l.), Anfu County, Jiangxi province. Male SYS a005511 collected by Zhi-Tong Lyu, Jian Wang and Hai-Long He on 13 September 2016 from Mt Mufu (28.9750N, 113.8304E; ca 1200 m a.s.l.), Pingjiang County, Hunan province. Males SYS a006494, SYS a006495/ CIB 110014, and females SYS a006451, 6496, collected by Zhi-Tong Lyu on 5-6 August 2017 from Mt Dawei (28.4250N, 114.0805E; ca 800 m a.s.l.), Liuyang City, Hunan province.

Etymology.

The specific name jiulingensis is in reference to the type locality, Guanshan Nature Reserve in Jiuling Mountains.

Suggested common name.

Jiuling Mountains Brown Frog (in English), Jiu Ling Shan Lin Wa (九岭山林蛙 in Chinese)

Diagnosis.

Rana jiulingensis sp. nov. is distinguished by the following morphological characteristics: (1) body medium-sized, SVL = 48.3-57.8 (51.7 ± 4.3, n = 4) mm in adult males, 48.2-57.5 (50.8 ± 4.4, n = 4) mm in adult females; (2) head length significantly larger than head width; (3) supratympanic fold absent; (4) dorsolateral fold distinct and thin, extending straight from posterior margin of upper eyelid to above groin; (5) internarial distances larger than interorbital distances; (6) tympanum diameter significantly smaller than eye diameter, TD/ED = 0.63-0.87; (7) fingers without circummarginal grooves, unwebbed, relative finger lengths I <II <IV <III; (8) presence of supernumerary tubercles below the bases of each finger, presence of three separated metacarpal tubercles; (9) toes without circummarginal grooves, toe webbing formula: I 1⅓ - 2 II 1⅓ - 2⅓ III 1 ½ - 2⅔ IV 3 - 1⅓ V, relative toe lengths I <II <III <V <IV; (10) tibio-tarsal articulation reaching forward beyond tip of snout; (11) heels overlapping; (12) dorsal skin smooth, flanks smooth with few granules; (13) absence of vocal sacs in males; (14) breeding males possess creamy white nuptial pad with tiny hoar spines on the finger I, divided into three parts; (15) presence of reddish tubercles on loreal and temporal regions in breeding males.

Description of holotype.

SYS a005519, adult male, SVL 57.8 mm. Head length significantly larger than head width (HW/HL = 0.85); snout pointed and projecting; nostril closer to tip of snout than eye; canthus rostralis distinct; internasal distance slightly larger than interorbital distance; tympanum rounded, smaller than eye (TD/ED = 0.72); tympanic rim prominent; pupil horizontal; loreal region concave, sloping outwards; vomerine teeth present; tongue deeply notched posteriorly; vocal sacs absent.

Forearms 0.19 of SVL and hand 0.26 of SVL; fingers slender, without web but with narrow fringe; tip of fingers rounded, not expanded, without circummarginal grooves; relative finger lengths I <II <IV <III; subarticular tubercles significantly prominent, rounded; distinct, small, rounded supernumerary tubercles below the bases of each finger; inner metacarpal tubercle indistinct, ovoid, partly covered by nuptial pad; two outer metacarpal tubercles distinctly separated, slightly larger, long elliptic; nuptial pad with tiny spines on the finger I, divided into three parts, the basal one around the inner metacarpal tubercle and partly covering it, the largest one from the edge of the basal one to the subarticular tubercle of finger I, the smallest one extending from the edge of the biggest one to the tip of finger I.

Tibia 0.63 of SVL and foot 0.88 of SVL; heels overlapping when hindlimbs flexed at right angles to axis of body; tibio-tarsal articulation reaching forward beyond the tip of snout when hindlimb stretched along the side of the body; relative toe lengths I <II <III <V <IV; toes webbing formula: I 1⅓ - 2 II 1⅓ - 2⅓ III 1 ½ - 2⅔ IV 3 - 1⅓ V; absence of lateral fringes on the lateral edges of toes I and V; subarticular tubercles oval and distinct; inner metatarsal tubercle large, ovoid, outer metatarsal tubercle small.

Dorsal skin smooth with sparse tiny granules; several small tubercles on flank; supratympanic fold absent; dorsolateral fold distinct and thin, extending straight from posterior margin of upper eyelid to above groin; several tiny granules on the skin of loreal and temporal regions; ventral surface smooth, large flattened tubercles densely arranged on the rear of thigh and around vent.

Coloration of holotype.

In life, dorsal surface yellowish brown with few black spots; black speckles forming a linear stripe between eyelids; dorsolateral fold intermittently edged with black on two sides; loreal region yellowish; temporal region yellowish, slightly tinged with grey; tiny granules on loreal and temporal regions reddish; dorsal forelimbs and hindlimbs reddish with indistinct greenish grey transverse bars. Throat yellowish; chest and belly creamy white; ventral surface of forelimbs and hindlimbs flesh color; nuptial pad creamy white; tubercles around vent yellowish.

In preservative, dorsal surface turns grey with black spots and light grey patches; limbs taupe with brown transverse bars. Ventral surface white, with greyish mottling on throat and belly; ventral surface of limbs beige; hands and toe webs dark grey.

Variations.

Measurements of type series specimens are given in Table 2 . Coloration of dorsal skin varies from brown to yellowish brown (Fig. 4 ). Black edges on dorsolateral fold indistinct in all paratypes. SYS a006495 and 6496 with V-shaped mark. The number of transverse bars ranges from two to five on forearms, three or four on thigh, and three to six on tibia.

Distribution and ecology.

Currently, Rana jiulingensis sp. nov. is known from Guanshan Nature Reserve in the Jiuling Mountains and Mount Wugong in the Wugong Mountains of northwestern Jiangxi, and Mount Mufu and Mount Dawei in the Mufu Mountains of northeastern Hunan. This suggests that its geographic distribution is the central and northern parts of the Luoxiao Range (Fig. 1 ). All individuals were found on the surface of paths or on the bush leaves beside paths in subtropical evergreen broadleaved forests. Males SYS a005511 and 5519, which were collected in mid-September, bear a well-developed nuptial pad, while males SYS a006494 and 6495, collected in early August, are without a nuptial pad. This suggests that the breeding season of this species might begin in September.

Figures

Figure 1. Collecting localities of Rana samples used in this study. Dotted line shows the Luoxiao Range, where five Rana species are recorded. Numbers correspond to the ID in Table 1.

Figure 3. Morphological features of the adult male holotype SYS a 005519 of Rana jiulingensis sp. nov. in life. A dorsolateral view B dorsal view C ventral view D grey nuptial pad E left hand F left foot.

Figure 4. Variations of Rana jiulingensis sp. nov. A, B dorsolateral view and ventral view of male paratype SYS a 006495 C male paratype SYS a 006496 D male paratype SYS a 00511.