Leptobrachella xinshaoensis sp. nov.

Type material.

Holotype. • CIB XS 20240319001 (Figs 3, 4), adult male, from Xinshao County, Hunan Province, China (27.5065°N, 111.4597°E, ca. 350 m a. s. l.), collected by Jing Liu on 19 March 2024.

Paratype. • Two male specimens, CIB XS 20240319002 and CIB XS 20240319003, collected on 19 March 2024 by Jing Liu from the same place as the holotype.

Etymology.

The specific epithet “xinshaoensis” refers to the name of the type locality, Xinshao County, Hunan, China. We suggest the English name “ Xinshao Leaf-litter Toad ” and the Chinese name “ Xin Shao Zhang Tu Chan (新邵掌突蟾) ”.

Diagnosis.

Leptobrachella xinshaoensis sp. nov. can be distinguished from its congeners by a combination of the following characters: (1) SVL 27.8–31.4 mm in males; (2) toes rudimentary webbed, lateral fringes on toes narrow; (3) tympanum distinct, surrounded by distinct tubercles; (4) dorsal surface shagreened with small, raised tubercles and longitudinal ridges; (5) ventral surface creamy white with dark brown spots on chest and margins; (6) distinct black spots present on flanks; (7) heels not meeting when hindlimbs flexed at right angles to the axis of body; (8) tibia-tarsal articulation reaching between eye and tympanum.

Description of holotype.

Adult male, body size medium (SVL 31.4 mm); head length (HDL 9.6 mm) greater than head width (HDW 8.8 mm); snout rounded in ventral and lateral views, projecting slightly beyond margin of the lower jaw; nostril closer to snout than eye; loreal region particularly oblique; eye diameter (ED 3.7 mm) slightly shorter than snout length (SL 4.7 mm); eyes notably protuberant in the dorsal and lateral views, pupil vertical, copper-colored iris; tympanum distinct, rounded; tympanum diameter (TD 2.1 mm), beyond half the eye diameter, upper margin in contact with supratympanic ridge; tongue notched behind; vomerine teeth absent; supratympanic ridge distinct, extending from the posterior corner of the eye to the supra-axillary gland.

Forelimb slender, length of lower arm and hand slightly shorter than half of the snout-vent length (LAL / SVL = 0.47); relative finger length I <II <IV <III; subarticular tubercles absent on fingers; supernumerary tubercles absent; finger webbing absent; lateral fringes absent; a large, round inner metacarpal tubercle, distinctly separated from small, laterally compressed outer metacarpal tubercle (Figs 3, 4).

Hindlimbs long, 1.35 times the snout-vent length; tibiotarsal articulation reaching between eye and tympanum when hindlimb is stretched along the side of the body; heels not meeting when hindlimbs are flexed and held perpendicular to body; tips of toes rounded, slightly swollen; relative length of toes: IV> III> V> II> I; subarticular tubercles indistinct under the base of II and III toe; narrow lateral fringes present on all toes; rudimentary webbing between toes; inner metatarsal tubercle distinct and prolonged, outer metatarsal tubercle absent (Figs 3, 4).

The dorsum bears sparse large warts, dense fine wart granules, and ridges; the upper eyelids, tympanic region, and dorsal surfaces of limbs are densely covered with small wart granules; the flanks possess large glandular warts; the forearms and tibiotarsal joint surfaces exhibit wart granules fused into longitudinal ridges; the inner side of the shank and the perianal region bear white conical spines; the pectoral and femoral glands are oval; the femoral glands are located on the posteroventral surface of the thigh, closer to the knee than to the vent; the supra-axillary gland is raised; the ventrolateral glandular line is distinctly visible.

Coloration of holotype in life.

The dorsal surface is brown with rough skin bearing sparse, large warts. An inverted brown triangular marking is present between the eyes, followed by a “ W ” - shaped marking on the anterior mid-dorsum. The flanks exhibit black spots interspersed with two rows of large warts. The supra-axillary gland is orange, while the pectoral gland is indistinct. The femoral gland is small and white. The upper part of the forelimbs is orange, and the lower part displays black transverse bars. The hindlimbs feature black transverse bars, with rough skin and raised skin folds on the dorsal surface of the thighs. Both fingers and toes exhibit transverse bars. The ventral surface is creamy white, with indistinct brown markings on the lateral abdomen and chest. The jaw and throat are pinkish, with small white spots scattered along the lower lip margin. The inner thighs are pinkish with small white warts, while the outer thighs bear brown spots.

Coloration of holotype in preservation.

After three months in 75 % ethanol, the dorsal background color had faded to dark brown; dark vertical bars, transverse bars, and black spots remained distinctly visible. The orange pigmentation on tubercles, glands, and elbows had completely faded. The ventral surfaces of the limbs appeared light brown, with brown markings along the abdominal margin becoming more distinct, while the chin and chest had gradually transitioned to light brown. The iris was uniformly dark gray.

Variation.

Measurements of the type series are summarized in Table 3. All paratypes resemble the holotype in overall morphology, except for the following variations: The dorsal surface exhibits a darker coloration (Fig. 5 A, C). Additionally, specimen CIB XS 20240319002 shows a whiter abdominal coloration (Fig. 5 B), while the posterior margin of the abdomen in specimen CIB XS 20240319003 is pale purple (Fig. 5 D).

Secondary sexual character.

Adult males with subgular vocal sacs, femoral adipose glands present on posterior surface of thigh. Nuptial pads and spines absent on males.

Distribution and habitats.

Leptobrachella xinshaoensis sp. nov. was found on plant leaves near mountain streams with relatively torrential flow (Fig. 6). During the survey, no female individuals, eggs, or tadpoles were found, and its breeding season is speculated to be around late March.