Scutiger pardalotus, Wang & Yu & Wu & Hou & Wang & Xiong & Ye & Duan & Li & Li & Jin & Yang & Che, 2025

Scutiger pardalotus sp. nov. Wang, Yu, and Che ( Figs. 3 View FIGURE 3 , 8 View FIGURE 8 , 9 View FIGURE 9 , and 12)

Holotype: KIZ 039283 View Materials , adult male, collected from the E’ga Pass , Luobenzhuo Village , Lushui County, Nujiang Lisu Autonomous Prefecture , Yunnan Province, China ( 98.74384ºE, 26.42762ºN, elevation 3081 m, GCJ02 ) by Zhong-Bin Yu and Shao-Bing Hou 30 October, 2021. GoogleMaps

Paratypes ( six adult males, one adult female): KIZ 038628 View Materials , 038640 View Materials , 038644 View Materials , adult males, KIZ 038641 View Materials , adult female, from Tingming Lake , Lushui County, Nujiang Lisu Autonomous Prefecture , Yunnan Province, China ( 98.68500ºE, 26.05722ºN, elevation 3546 m, GCJ02 ) by Zhong-Bin Yu , Dong An , and Tian-En Chen on 4 August, 2021 GoogleMaps ; KIZ 038629 View Materials , 038631 View Materials , adult males, from Pianma , Lushui County, Nujiang Lisu Autonomous Prefecture, Yunnan Province, China ( 98.63600ºE, 25.98334ºN, elevation 2307 m, GCJ02 ) by Zhong-Bin Yu, Dong An, and Tian-En Chen on 4 August 2021 GoogleMaps .

Etymology: The species name “ pardalotus ” is derived from Greek, which means “spotted like a leopard”. It describes the beautiful spotted coloration patterns on the dorsum of the species. The proposed Chinese common name of the new species is “ ËỄÊẊḆ ” (pinyin: Bao Ban Chi Tu Chan), and the proposed English name is Leopard Lazy Toad.

Diagnosis: Scutiger pardalotus sp. nov. can be diagnosed from all congeners by a combination of the following morphological characters: (1) body size moderate, SVL 47.5–56.4mm; (2) forearm and hand length moderate, LFHL 43.0–49.9% SVL; (3) posterior head moderate, PHL 34.7–42.5% HL; (4) inter-nare distance long, IND 21.6–29.4% HW; (5) snout long, SEL 37.5–45.2% HL; (6) eyes large, ED 20.5–28.4% HL; (5) single pair of pectoral glands and single pair of axillary glands present in males; (6) fine spines present on pectoral glands, but not on peripheral margin of chin on ventral head nor axillary glands; (7) maxillary teeth present; (8) tongue rounded; (9) nuptial pads present only on first two fingers in males, covered with a few distinctively enlarged black spines; (10) no distinct enlarged, raised tubercles scattered on dorsal and lateral forearms and anterior brachium; (11) no raised tubercles present on dorsal eyelids and supralabial; (12) vocal sacs present; (13) supratympanic fold strongly developed, extend posterior of axillary; (14) toes with distinct, well developed dermal fringes and well developed webbing, reaching tip of toe I and half webbed on toe II and III; (15) parietal head flat; (16) dorsum smooth or with a few relatively flat tubercles; and (17) dorsal surface Pale Pinkish Buff (Color 3) to Light Orange Yellow (Color 7), speckled with Brunt Umber (Color 48), irregular spots and dorsolateral stripes.

Comparisons: The new species is morphologically most similar to and phylogenetically sister to S. gongshanensis , but S. pardalotus sp. nov. can be diagnosed from the S. gongshanensis readily by having differential webbing between toes (half-webbed vs. only feebly webbed).

From the other new species described above, S. pardalotus sp. nov. differs from S. lisu sp. nov. by having a smaller body size in adults (SVL < 56.4mm vs. ≥ 75.2mm), longer snout (SEL 36.4–45.2% HL vs. 33.4–35.3%), smaller patches of pectoral glands in males (vs. much larger), different webbing on toes (half webbed vs. feebly webbed), better developed dermal fringes on toes (vs. much weaker), a distinct dorsal coloration (dorsal surface Pale Pinkish Buff [Color 3] to Light Orange Yellow [Color 7], speckled with Brunt Umber [Color 48], irregular spots and dorsolateral stripes vs. dorsal surface near uniformly Grayish Horn Color [Color 268] to Hair Brown [Color 277]), as well as by the presence of vocal sacs in males (vs. absence).

For species distributed closely along the Gaoligong Mountain and the adjacent Biluo Snow Mountain, S. pardalotus sp. nov. differs from all by the presence of vocal sacs (vs. absence) and a spotted coloration pattern (vs. uniformly colored or not heavily spotted). Additionally, S. pardalotus sp. nov. differs from S. biluoensis , S. meiliensis , S. tengchongensis by the absence of distinct axillary glands in males (vs. presence) and by a differential webbing between toes (half webbed vs. no webbing or only feebly webbed).

For remaining species of the genus, S. pardalotus sp. nov. differs from the S. boulengeri complex (including S. boulengeri and S. bangdaensis , as well as the two synonyms of S. boulengeri , namely Cophophryne alticola and Aelurophryne tainingensis ), as well as from S. bhutanensis , S. chintingensis , S. ghunsa , S. glandulatus , S. jiulongensis , S. liupanensis , S. mammatus , S. maculatus , S. nepalensis , S. ningshanensis , S. nyingchiensis , S. pingwuensis , S. sikimmensis S. spinosus , S. tuberculatus , S. wanglangensis , S. wolong , and S. wuguanfui by the absence of nuptial spines on axillary glands in breeding males (vs. presence); from S. muliensis , S. nyingchiensis , S. sikkimensis by the presence of maxillary teeth (vs. absence); from S. adungensis by much weaker toe webbings (half webbed vs. one-fourth or less) and by the absence of distinct round tubercles on dorsum (vs. presence); and from S. chintingensis , S. liupanensis , S. ningshanensis , S. wanglangensis , and S. wolong by the presence of vocal sacs (vs. absence).

Description of holotype: Adult male, body moderate, SVL 52.6 mm; head large, dorsally compressed, width about equal to length, HW 99.4% HL; parietal region slightly concave; snout relatively long, slightly pointy anteriorly, projecting beyond jaw, SEL 41.4% HL; lateral supralabial convex posterior to nares; nares closer to snout than eyes, facing dorsolaterally, further apart from each other, IN 25.1% HW; loreal not concave; canthus rostralis distinct; eye raised, large, ED 27.6% HL, DEW 23.6% HL; iris ellipse shaped, vertically oriented; tympanum concealed; frontal and temporal flat; supratympanic folds strongly developed, raised, extending posteriorly to posterior jaw only.

Limbs sturdy; forearm muscular, FAL 48.1% SVL, thicken toward elbows, FAW 25.2% FAL; fingers relative thick, short, free of webbing, finger length I<II<IV<III; a few, distinctively enlarged, raised nuptial spines present on each of first two fingers; metacarpal tubercles and subdigital tubercles indistinct. Hindlimb muscular, strong, relatively short, heels not meeting anteriorly and reaching shoulder with tip of longest toe when adpressed, HLL 127.1% SVL, FEM 38.5% SVL, TFL 64.3% SVL, TIB 36.0% SVL; foot longer than tibia, FL 122.6% TIB; toe tips rounded, toe length I<II <III <V <IV; toes with distinct dermal fringes, well developed; webbing well developed, webbing formula I1–2 - II 11/2 –2 + III2–3 + IV4 - – 21/2 V; subdigital tubercles present on inner two toes, indistinct under remining ones; subarticular tubercles absent, subdigital ridges distinct; inner metatarsal tubercle distinct, oval shaped, about same length as first toe, outer metacarpal tubercle absent.

Dorsal skins of head, body, and limbs smooth overall, with few flat warts and tubercles on dorsum; fine tubercles covering regions from posterior supralabial to corner of mouth inferior of supratympanic fold; dorsal head smooth; tubercles on dorsum moderate in size, feebly raised; dorsal forelimbs smooth, medial side with few raised tubercles; skin of hindlimbs smooth. Areas near cloaca with few flat tubercles.

No spines on ventral lower lip;single pair of pectoral glands present on chest, elongated, oriented lateroposteriorly, covered with residuals of fine spines; single pair of axillary gland distinct, free from spines; remaining ventral body smooth.

Coloration: In life, the dorsal background coloration is Warm Buff (Color 4) to Salmon Color (Color 58), and the remaining coloration patterns of the dorsal surfaces are all Brunt Umber (Color 48). A distinct eye stripe is present from the tip of snout to the corner of mouth along the inferior edge of supratympanic fold on each side. A single “T”-shaped pattern is situated on dorsal head, with the top of the T-figure located between eyes and tip of the T-figure extending till mid dorsum. Two parallel, somewhat irregular, dorsolateral stripes are present lateral of the T-figure from the temporal head to the groin. Dense circular spots and irregular patches of Brunt Umber (Color 48) are scattered on remaining areas of dorsum and dorsal limbs, with the lateral ones arranged in somewhat lines.

The ventral background coloration is Rose Pink (Color 243). An intermixed Pale Pinksih Buff (Color 3) and Walnut Brown (Color 27) marble patterns are present on lower chin, ventrolateral body, and ventrolateral limbs. Nuptial spines on finger Jet Black (Color 300).

Variation: Although only female is available, in addition to the lack of nuptial spines on fingers and the absence of pectoral glands, sexual dimorphism is evident, where the female is slightly larger than males (SVL 56.4mm vs. 51.1–52.8mm), has thinner arms (FAW 22% FAL vs.25.2–32.8%), shorter arms and hands (LFHL 43% SVL vs. 46.9–49.9%), shorter hind limbs (HLL 123.3% SVL vs. 138.9–145.5%).

Among male specimens, only the holotype has completely developed nuptial spines on fingers (i.e. nuptial spines completely covered with a continuous black keratin layer), where spines of all remaining males (KIZ 038628, 038629, 038631, 038640, 038644, and 039283) are under development. KIZ 038640 has only a dark vertebral stripe, where the dorsolateral stripe on each side of the vertebral stripe is replaced by dorsolateral series of spots. Webbing formula remains consistent among males and does not differ between the two sexes.

Natural history and conservation: Currently S. pardalotus sp. nov. is known from the two localities only, which are about 40 km apart in linear distance along the Gaoligong Mountain Range ( Fig. 1 View FIGURE 1 ). It is likely to occur in additional sites along the mountain range in both China and Myanmar. The only known amphibian species sympatric with the new species is Amolops yangi . Most individuals of S. pardalotus sp. nov. were found along shoreline of lakes at night ( Fig. 12 View FIGURE 12 , D and E), while a few were spotted in the forests at night close to the lake. Newly hatched tadpoles were found under rocks in the water in late October, and the female paratype (KIZ 038641) collected in September was gravid, so the breeding season might be between August and October. Individuals were found commonly infested with green aquatic leaches. With little known on the natural history and distribution range of the species, we recommend list it as Data Deficient (DD) for its conservation status, pending on future studies.