Leptobrachella darongshanensis, Chen & Bei & Li, 2025

Chen, Wei-Cai, Bei, Yong-Jian & Li, Peng, 2025, A new species of the genus Leptobrachella (Amphibia, Anura, Megophryidae) from the Darongshan Nature Reserve, Guangxi, China, ZooKeys 1260, pp. 171-194 : 171-194

publication ID	https://doi.org/10.3897/zookeys.1260.161514
publication LSID	lsid:zoobank.org:pub:0F8F8B32-7095-45BC-806B-71854F223827
DOI	https://doi.org/10.5281/zenodo.17652503
persistent identifier	https://treatment.plazi.org/id/E7C60536-0146-577F-82EF-8C054A7497E5
treatment provided by	ZooKeys by Pensoft
scientific name	Leptobrachella darongshanensis
status	sp. nov.

Treatment

Leptobrachella darongshanensis sp. nov.

Fig. 4 A – F View Figure 4

Type material.

Holotype • NNU 001390 , adult male, collected at Darongshan Nature Reserve , Yulin City, Guangxi, China ( 22.868°N, 110.202°E; elevation 1048 m) by Wei-Cai Chen on 19 March 2025 GoogleMaps .

Paratypes • NNU 001152 –001153 ( two adult males), NNU 001157 –001161 ( four adult females), collected at the same locality as the holotype on 17 May 2023 by Wei-Cai Chen and Yong-Jian Bei GoogleMaps . • NNU 001391 –001393 ( three adult males), NNU 001394 –001397 ( four adult females), collected at the same locality as the holotype on 19 March 2025 by Wei-Cai Chen GoogleMaps .

Diagnosis.

Leptobrachella darongshanensis sp. nov. is assigned to the genus Leptobrachella based on molecular phylogenetic results and the following generic morphological characters: small size, presence of an inner metacarpal tubercle, absence of vomerine teeth, distinct tympanum, and the presence of macro-glands (pectoral and femoral glands, often including supra-axillary and ventrolateral glands). Leptobrachella darongshanensis sp. nov. can be distinguished from its congeners by the following combination of characters: (1) medium body size ( SVL 24.9–27.7 mm in males; 32.0– 35.4 mm in females); (2) dorsal skin rough with small, raised tubercles and ridges; (3) ventral surface creamy white with minute irregular textures and tiny pale brown spots laterally on the belly; (4) flanks bearing irregular black spots; (5) distinct black supratympanic line extending from posterior corner of eye to supra-axillary gland; (6) rudimentary toe webbing present between toes I – IV, lateral dermal fringes absent on toes; (7) ventrolateral glandular line distinct and continuous; (8) iris bicolored, upper half tangerine, lower half silver with black reticulations; pupil black with tangerine edges; (9) tibiotarsal articulation reaching the posterior margin of the eye when hindlimb is adpressed along body; (10) advertisement call dominant frequency 6.1–6.7 kHz at 20.0 ° C.

Description of holotype.

Adult male ( SVL 27.7 mm). Head width subequal to length ( HW / HL = 0.98). Snout projecting, extending beyond lower jaw; nostril oval, closer to snout tip than to eye; canthus rostralis rounded; loreal region concave, sloping towards lips; interorbital region flat; pupil vertical; eye diameter larger than snout length ( ED / SNT = 1.16); internarial distance subequal to interorbital distance ( IN / IOD = 0.98); tympanum distinct, round, concave, diameter much smaller than eye diameter ( TD / ED = 0.44); distinct, raised supratympanic fold extending from posterior corner of eye to supra-axillary gland. Vomerine teeth absent. Tongue pyriform, notched posteriorly.

Fingers lacking webbing and lateral fringes; tips slightly swollen; relative finger lengths I <II <IV <III; nuptial pads absent; subarticular tubercles absent; inner palmar tubercle prominent, oval; outer palmar tubercle prominent, rounded; inner and outer palmar tubercles separated. Toes lacking lateral fringes, tips rounded, not swollen; relative toe lengths I <II <V <III <IV; subarticular tubercles absent, replaced by low, indistinct dermal ridges; inner metatarsal tubercle large, elongated; outer metatarsal tubercle absent; webbing rudimentary between toes I – IV. Tibia length ~ 47 % of SVL ( TIB / SVL = 0.47); tibiotarsal articulation reaching posterior margin of eye when hindlimb is adpressed anteriad; heels not meeting when thighs are held at right angles to body axis (Fig. 4 A – F View Figure 4 ).

Dorsal skin texture rough with numerous small, raised tubercles and short ridges; ventral skin smooth; pectoral glands oval, creamy white, ~ 1.4 mm in diameter; femoral glands oval, ~ 1.1 mm in diameter, positioned closer to knee than to vent; supra-axillary glands small, round, ~ 1.0 mm in diameter; ventrolateral glandular line distinct and continuous; limbs with sparse tubercles; a pair of small tubercles present above the cloaca (Fig. 4 A – F View Figure 4 ).

Color of holotype in life. Dorsum brown with distinct chocolate markings, including a dark brown triangular marking between eyes and a dark brown ‘ W’ - shaped marking on the scapular region, interspersed with irregular dark spots; tympanum pale brown; distinct black supratympanic line from posterior corner of eye to supra-axillary gland; three dark brown spots on upper lip; flanks with five irregular black spots and numerous small creamy yellow tubercles; dorsal surfaces of hindlimbs with three distinct transverse dark brown bars; dorsal surfaces of forelimbs with three transverse dark brown bars; elbows, upper arms, and tibiotarsal regions pale yellow; ventral surface creamy white with minute irregular textures and tiny pale brown spots laterally on belly; throat and chest pale pinkish; pectoral and femoral glands creamy white; supra-axillary glands pale yellow; iris bicolored, upper half tangerine, lower half silver with black reticulations; pupil black, surrounded by a tangerine ring (Fig. 4 A – F View Figure 4 ).

Color of holotype in preservative. Dorsum dark brown; transverse dark bars on limbs distinct; ventral surfaces creamy white; pectoral, femoral, supra-axillary, and ventrolateral glands creamy white.

Variation. Measurements of the type series are presented in Table 3 View Table 3 . Coloration and pattern in paratypes are generally consistent with the holotype (Fig. 5 View Figure 5 ). Variation is observed primarily in the intensity and distribution of dark dorsal spots and flank spots. For example, specimen NNU 001394 exhibits more pronounced brown dorsal spotting (Fig. 5 D View Figure 5 ).

Measurements of holotype (in mm): SVL 27.7, HL 9.5, HW 9.3, SNT 3.4, ED 4.0, IOD 2.6, TD 1.8, IN 2.5, TIB 12.9, FLL 13.5, TFL 19.1, ML 7.1, HLL 39.1, FG-knee 4.1.

Ecology and distribution.

Leptobrachella darongshanensis sp. nov. is currently known only from montane evergreen broad-leaved forest within the Darongshan Nature Reserve, Yulin City, Guangxi, China, at elevations between 800 and 1,200 m a. s. l. Individuals were found calling near rocky streams from March to May. All females collected in March were gravid (Fig. 5 E – G View Figure 5 ). The new species occurs syntopically with L. yunkaiensis along the same stream sections.

Etymology.

The specific epithet darongshanensis is a toponym derived from the type locality, Mt. Darongshan. The suggested English common name is Darongshan Leaf Litter Toad. The suggested Chinese common name is Da Rong Shan Zhang Tu Chan (大容山掌突蟾).

Comparisons.

Comparisons focus on phylogenetically close relatives (Fig. 2 View Figure 2 ) and the sympatric species L. yunkaiensis . Leptobrachella darongshanensis sp. nov. differs from its sister species L. shiwandashanensis by: larger relative eye diameter ( ED / SNT = 1.16 vs 0.92); black (vs grey) supratympanic line; rudimentary toe webbing on toes I – IV (vs webbing absent); continuous (vs interrupted) ventrolateral glandular line; pupil ringed with tangerine (vs no distinct colored ring); iris bicolored, upper half tangerine, lower half silver with black reticulations (vs upper half brownish-red, lower half silver). Significant bioacoustic differences exist: shorter call duration (77.9 ± 14.5 ms vs 226.6 ± 16.4 ms), longer call interval (521.2 ± 106.7 ms vs mean 153.1 ms), and higher dominant frequency (6.1–6.7 kHz vs 5.3–5.7 kHz) (Table 2 View Table 2 , Fig. 3 View Figure 3 ).

Leptobrachella darongshanensis sp. nov. differs from L. aerea ( Rowley, Stuart, Richards, Phimmachak & Sivongxay, 2010) by: absence of lateral dermal fringes on toes (vs narrow fringes present); relative finger lengths I <II <IV <III (vs I <II = IV <III); tibiotarsal articulation reaching posterior eye margin (vs reaching snout tip) when leg adpressed.

Leptobrachella darongshanensis sp. nov. differs from L. aspera Wang, Lyu, Qi & Wang, 2020 by: larger body size in males ( SVL 24.9–27.7 mm vs 22.4 mm in single male) and females (32.0– 35.4 mm vs 25.0– 26.4 mm); iris bicolored, upper tangerine, lower silver with black reticulations (vs upper amber, lower silver); absence of lateral dermal fringes on toes (vs narrow fringes present); venter creamy white with minute textures (vs creamy white with distinct regular dark patches).

Leptobrachella darongshanensis sp. nov. differs from L. damingshanensis Chen, Yu, Cheng, Meng, Wei, Zhou & Lu, 2021 and L. nahangensis ( Lathrop, Murphy, Orlov & Ho, 1998) by: significantly smaller male body size ( SVL 24.9–27.7 mm vs 33.6–34.4 mm in L. damingshanensis , 40.8 mm in L. nahangensis ).

Leptobrachella darongshanensis sp. nov. differs from L. feii Chen, Yuan & Che, 2020 by: larger body size in males ( SVL 24.9–27.7 mm vs 21.5–22.7 mm) and females (32.0– 35.4 mm vs 25.7 mm in single female); venter creamy white with minute textures (vs distinct black blotches on chest and belly); absence of lateral dermal fringes on toes (vs narrow fringes present).

Leptobrachella darongshanensis sp. nov. differs from L. guinanensis Chen, Li, Peng & Liu, 2024 by: smaller body size in males ( SVL 24.9–27.7 mm vs 30.5–32.5 mm) and females (32.0– 35.4 mm vs 38.7–41.8 mm); absence of lateral dermal fringes on toes (vs wide fringes present); rudimentary toe webbing (vs webbing basal, ~ 1 / 3 webbed); iris bicolored, upper tangerine, lower silver with black reticulations (vs upper pale copper, lower silver).

Leptobrachella darongshanensis sp. nov. differs from L. minima ( Taylor, 1962) by: rough dorsal skin with tubercles and ridges (vs dorsum smooth); iris bicolored, upper tangerine, lower silver with black reticulations (vs upper dark gold, lower gray).

Leptobrachella darongshanensis sp. nov. differs from L. pelodytoides ( Boulenger, 1893) by: absence of lateral dermal fringes on toes (vs narrow fringes present); rudimentary toe webbing (vs extensive webbing).

Leptobrachella darongshanensis sp. nov. differs from L. phiadenensis Luong, Hoang, Pham, Ziegler & Nguyen, 2023 by: absence of lateral dermal fringes on toes (vs narrow fringes present); rudimentary toe webbing (vs webbing absent); black supratympanic line (vs orange); venter creamy white with minute textures (vs white with dark speckling on outer margins).

Leptobrachella darongshanensis sp. nov. differs from L. pluvialis ( Ohler, Marquis, Swan & Grosjean, 2000) by: larger male body size ( SVL 24.9–27.7 mm vs 21.3–22.3 mm); creamy white venter with minute textures (vs pigmented venter); tibiotarsal articulation reaching posterior eye margin (vs reaching nostril) when leg adpressed.

Leptobrachella darongshanensis sp. nov. differs from L. shangsiensis Chen, Liao, Zhou & Mo, 2019 by: absence of lateral dermal fringes on toes (vs narrow fringes present); larger relative eye diameter ( ED / SNT = 1.16 vs 0.78); continuous ventrolateral glandular line (vs discrete glands).

Leptobrachella darongshanensis sp. nov. differs from L. ventripunctata (Fei, Ye & Li, 1990) by: creamy white venter with minute textures and tiny lateral spots (vs belly creamy white with numerous scattered brown spots); rudimentary toe webbing on toes I – IV (vs webbing absent).

Leptobrachella darongshanensis sp. nov. differs from L. wuhuangmontis Wang, Yang & Wang, 2018 by: iris bicolored, upper tangerine, lower silver with black reticulations (vs upper coppery yellow, lower silver); venter creamy white with minute textures and tiny lateral pale brown spots (vs greyish white mixed with tiny white and black dots); rudimentary toe webbing and absence of lateral fringes on toes (vs toes with narrow lateral fringes and rudimentary webbing).

Leptobrachella darongshanensis sp. nov. occurs syntopically with L. yunkaiensis . The new species differs from L. yunkaiensis by: creamy white venter with minute textures and tiny lateral pale brown spots (vs belly pinkish with distinct or indistinct pale / dark brown speckling); absence of lateral dermal fringes on fingers (vs distinct fringes present); absence of lateral dermal fringes on toes (vs wide fringes present).

Leptobrachella darongshanensis sp. nov. differs from congeners occurring south of the Isthmus of Kra (e. g., L. arayai ( Matsui, 1997) , L. dringi ( Dubois, 1987) , L. fritinniens ( Dehling & Matsui, 2013) , L. gracilis ( Günther, 1872) , L. hamidi ( Matsui, 1997) , L. heteropus ( Boulenger, 1900) , L. kajangensis ( Grismer, Grismer & Youmans, 2004) , L. kecil ( Matsui, Belabut, Ahmad & Yong, 2009) , L. marmorata ( Matsui, Zainudin & Nishikawa, 2014) , L. maura ( Inger, Lakim, Biun & Yambun, 1997) , L. melanoleuca ( Matsui, 2006) , L. picta Malkmus, 1992 , L. platycephala ( Dehling, 2012) , L. sabahmontana ( Matsui, Nishikawa & Yambun, 2014) , and L. sola Matsui, 2006 ) by the presence of supra-axillary glands and a distinct ventrolateral glandular line, which are absent in these species.