Megophrys qianbeiensis, Su & Shi & Wu & Li & Yao & Wang & Li, 2020

Su, Haijun, Shi, Shengchao, Wu, Yanqing, Li, Guangrong, Yao, Xiaogang, Wang, Bin & Li, Shize, 2020, Description of a new horned toad of Megophrys Kuhl & Van Hasselt, 1822 (Anura, Megophryidae) from southwest China, ZooKeys 974, pp. 131-159 : 131

Megophrys qianbeiensis sp. nov. Figures 4A1-C1 , 5 , 6A1-A6 , 7 ; Tables 1, 2, 4, 5, Suppl. material 2: Table S2

Type material

. Holotype. CIBTZ20190608017 (Figs 5 , 6 ), adult male, from Huanglian Nature Reserve, Tongzi County, Guizhou Province, China (28.498056°N, 107.046944°E, ca. 1500 m a.s.l.), collected by Shi-Ze Li 8 June 2019.

Paratype. Four adult males from the same place as holotype, and one from Kuankuoshui National Nature Reserve (28.21835°N, 107.166388°E, ca.1520 m a.s.l.) collected by Shi-Ze Li. CIBKKS20180722001 collected 22 July 2018 from Kuankuoshui National Nature Reserve and CIBTZ20160715003 collected 15 July 2016, CIBTZ20190608015, CIBTZ20190608016 and CIBTZ20190608018 collected 8 June 2019 from Kuankuoshui National Nature Reserve.

Diagnosis.

Megophrys qianbeiensis sp. nov. is assigned to the genus Megophrys based on molecular phylogenetic analyses and the following generic diagnostic characters: snout shield-like; projecting beyond the lower jaw; canthus rostralis distinct; chest glands small and round, closer to the axilla than to midventral line; femoral glands on rear part of thigh; vertical pupils.

Megophrys qianbeiensis sp. nov. could be distinguished from its congeners by a combination of the following morphological characters: body size moderate (SVL 49.3-58.2 mm in males); vomerine ridges present distinctly, vomerine teeth present; tongue feebly notched behind; tympanum distinctly visible, oval; two metacarpal tubercles in hand; toes with one-third webbing and wide lateral fringes; heels overlapped when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level between tympanum and eye when leg stretched forward; an internal single subgular vocal sac present in male; in breeding male, the nuptial pads with large and sparse black nuptial spines present on the dorsal bases of the first two fingers.

Description of holotype.

(Figs 5 , 6 ). SVL 56.3 mm; head width larger than head length (HDW/HDL ratio ca. 1.3); snout obtusely pointed, protruding well beyond the margin of the lower jaw in ventral view; loreal region vertical and concave; canthus rostralis well-developed; top of head flat in dorsal view; eye large, eye diameter 44.5 % of head length; pupils vertical; nostril orientated laterally, closer to snout than eye; tympanum distinct, TYP/EYE ratio 0.49; vomerine ridges present distinctly as V-shape, vomerine teeth present; margin of tongue smooth, feebly notched behind.

Forelimbs slender, the length of lower arm and hand 42.6 % of SVL; fingers burly, relative finger lengths: II <I <V <III; tips of digits globular, without lateral fringes; subarticular tubercle distinct at the base of each finger; two metacarpal tubercles, prominent, oval-shaped, the inner one bigger than the outer one.

Hindlimbs slender, 1.54 times of SVL; heels overlapping when thighs are positioned at right angles to the body, tibiotarsal articulation reaching tympanum to eye when leg stretched forward; tibia length longer than thigh length; relative toe lengths I <II <V <III <IV; tips of toes round, slightly dilated; subarticular tubercles present on the base of each toes; toes with one-third webbing and relative wide lateral fringe; inner metatarsal tubercle oval-shaped; outer metatarsal tubercle absent.

Dorsal skin rough, with numerous granules with black spins; several large warts scattered on flanks; tubercles on the dorsum forming a weak V-shaped ridge; two discontinuous dorsolateral parallel ridges on either side of the V-shaped ridges; an inverted triangular brown speckle between two upper eyelids; several tubercles on the flanks and dorsal surface of thighs and tibias; supratympanic fold distinct.

Ventral surface smooth with numerous white granules; glands on chest indistinct; femoral glands on rear of thighs, numerous white granules on outer thighs; posterior end of the body distinctly protruding and forming an arc-shaped swelling above the anal region.

Coloration of holotype in life

(Fig. 5 ). An inverted triangular brown speckle between the eyes; V-shaped ridges on the dorsum with brown speckle, on transverse bands on the dorsal surface of the thigh and shank; several dark brown and white vertical bars on the lower and upper lip; belly whitish grey with dark brown marbling; ventral surface of posterior limb orange with numerous granules; palms, soles and tip of digits uniform purple grey; femoral glands white.

Coloration of holotype in preservation

(Fig. 6 ). Color of dorsal surface fades to brownness; the inverted triangular brown speckle between the eyes and V-shaped ridges on dorsum indistinct; ventral surface greyish white; creamy-white substitutes the purple grey on tip of digits; the posterior of ventral surface of body, inner of thigh and upper of tibia fades to creamy-white.

Variation.

In CIBTZ20160715003 the dorsolateral parallel ridges are short, just a little bit above the shoulder (Fig. 7A ); in CIBTZ20190608015 the X-shaped marking on back of trunk consists of a ridge with brown spots (Fig. 7B ) and the posterior belly are orange with black spots on the flank belly (Fig. 7C ); in CIBKKS20180722001 the belly is grey brown with some white spots (Fig. 7D ).

Advertisement call.

The call description is based on recordings of the holotype CIBTZ20190608017 (Fig. 4 ) from the shrub leaf near the streamlet, and the ambient air temperature was 20.5 °C. Each call consists of 14-26 (mean 22.5 ± 4.4, N = 6) notes. Call duration was 2832-5621 ms (mean 4413 ± 972, N = 6). Call interval was 6812-14387 ms (mean 10878 ± 2701, N = 5). Each note had a duration of 129-211 ms (mean 167 ± 0.02, N = 135) and the intervals between notes 34-94 ms (mean 57 ± 0.01, N = 128). Amplitude modulation within note was apparent, beginning with moderately high energy pulses, increasing slightly to a maximum by approximately mid note, and then decreasing towards the end of each note. The average dominant frequency was 2469 ± 197.47 (2250-3000 Hz, N = 6).

Secondary sexual characters.

Adult males have a single subgular vocal sac. In breeding males, brownish red nuptial pads are present on the dorsal bases of the first two fingers with big and sparse black nuptial spines (Fig. 5A ).

Comparisons.

By having moderate body size (minimum SVL> 49.8 mm in males), Megophrys qianbeiensis sp. nov. differs from M. aceras , M. acuta , M. angka , M. ancrae , M. baluensis , M. baolongensis , M. binchuanensis , M. binlingensis , M. boettgeri , M. brachykolos , M. caobangensis , M. cheni , M. daweimontis , M. dongguanensis , M. dringi , M. edwardinae , M. elfina , M. fansipanensis , M. feii , M. gerti , M. hansi , M. hoanglienensis , M. huangshanensis , M. insularis , M. jiangi , M. jinggangensis , M. jiulianensis , M. kuatunensis , M. lancip , M. leishanensis , M. lini , M. lishuiensis , M. longipes , M. major , M. microstoma , M. minor , M. monticola , M. mufumontana , M. nankunensis , M. nanlingensis , M. obesa , M. ombrophila , M. oropedion , M. pachyproctus , M. palpebralespinosa , M. parallela , M. parva , M. rubrimera , M. serchhipii , M. shimentaina , M. shunhuangensis , M. tuberogranulata , M. vegrandis , M. wawuensis , M. wugongensis , M. wuliangshanensis , M. wushanensis , M. xianjuensis , M. zhangi , M. zunhebotoensis , M. xiangnanensis , and M. yangmingensis (vs. minimum SVL <48.0 mm).

By having moderate body size (minimum SVL <59.0 mm in males), Megophrys qianbeiensis sp. nov. differs from M. auralensis , M. carinense , M. caudoprocta , M. caudoprocta , M. chuannanensis , M. feae , M. gigantica , M. glandulosa , M. himalayana , M. kalimantanensis , M. kobayashii , M. ligayae , M. mangshanensis , M. orientalis , M. periosa , M. platyparietus , M. popei , M. shapingensis , and M. shuichengensis (vs. minimum SVL> 60.0 mm).

By having vomerine teeth, Megophrys qianbeiensis sp. nov. differs from M. aceras , M. acuta , M. angka , M. auralensis , M. baolongensis , M. binchuanensis , M. binlingensis , M. boettgeri , M. brachykolos , M. caobangensis , M. cheni , M. chishuiensis , M. dringi , M. jiangi , M. leishanensis , M. lini , M. lishuiensis , M. major , M. microstoma , M. minor ,. M. mirabilis , M. mufumontana , M. nankiangensis , M. obesa , M. ombrophila , M. shapingensis , M. shuichengensis , M. shunhuangensis , M. tuberogranulata , M. vegrandis , M. wawuensis , M. wugongensis , M. wuliangshanensis , M. wushanensis , M. xianjuensis , M. xiangnanensis , and M. yangmingensis (vs. absent).

By the absence of horn-like tubercle at the edge of each upper eyelid, Megophrys qianbeiensis sp. nov. differs from M. aceras , M. acuta , M. angka , M. ancrae , M. auralensis , M. baluensis , M. baolongensis , M. boettgeri , M. brachykolos , M. caobangensis , M. carinense , M. caudoprocta , M. cheni , M. chishuiensis , M. chuannanensis , M. daweimontis , M. dongguanensis , M. dringi , M. edwardinae , M. elfina , M. fansipanensis , M. feae , M. feii , M. flavipunctata , M. gerti , M. glandulosa , M. hansi , M. himalayana , M. hoanglienensis , M. huangshanensis , M. insularis , M. intermedia , M. jiangi , M. jingdongensis , M. jinggangensis , M. jiulianensis , M. kalimantanensis , M. koui , M. kuatunensis , M. lancip , M. leishanensis , M. lekaguli , M. liboensis , M. ligayae , M. lini , M. lishuiensis , M. longipes , M. mangshanensis , M. medogensis , M. microstoma , M. mirabilis , M. montana , M. mufumontana , M. nankunensis , M. nanlingensis , M. nasuta , M. obesa , M. ombrophila , M. omeimontis , M. oreocrypta , M. orientalis , M. palpebralespinosa , M. parallela , M. parva , M. periosa , M. platyparietus , M. popei , M. rubrimera , M. shimentaina , M. shuichengensis , M. shunhuangensis , M. stejnegeri , M. synoria , M. vegrandis , M. wugongensis , M. xianjuensis , M. xiangnanensis , and M. yangmingensis (vs. present).

With the tongue feebly notched behind, Megophrys qianbeiensis sp. nov. differs from M. aceras , M. acuta , M. angka , M. auralensis , M. brachykolos , M. caobangensis , M. caudoprocta , M. dongguanensis , M. elfina , M. hansi , M. jiangi , M. jinggangensis , M. lancip , M. leishanensis , M. lekaguli , M. lini , M. lishuiensis , M. megacephala , M. mufumontana , M. nankunensis , M. obesa , M. ombrophila , M. orientalis , M. palpebralespinosa , M. parallela , M. parva , M. shunhuangensis , M. takensis , M. wushanensis , and M. xianjuensis (vs. tongue not notched behind in the latter), and differs from M. cheni , M. damrei , M. dringi , M. flavipunctata , M. gigantica , and M. popei (vs. tongue notched behind).

By having lateral wide fringes on toes, Megophrys qianbeiensis sp. nov. differs from M. angka , M. baolongensis , M. brachykolos , M. caobangensis , M. damrei , M. daweimontis , M. dongguanensis , M. fansipanensis , M. feae , M. himalayana , M. hoanglienensis , M. huangshanensis , M. insularis , M. jiangi , M. jiulianensis , M. kalimantanensis , M. koui , M. leishanensis , M. lekaguli , M. lishuiensis , M. major , M. mangshanensis , M. medogensis , M. megacephala , M. microstoma , M. minor , M. nankunensis , M. obesa , M. ombrophila , M. oreocrypta , M. oropedion , M. pachyproctus , M. parva , M. periosa , M. shunhuangensis , M. takensis , M. tuberogranulata , M. wawuensis , M. wugongensis , M. wuliangshanensis , and M. xianjuensis (vs. lacking lateral fringes on toes).

By toes with one-third webs, Megophrys qianbeiensis sp. nov. differs from M. aceras , M. acuta , M. angka , M. auralensis , M. baluensis , M. baolongensis , M. binchuanensis , M. binlingensis , M. boettgeri , M. brachykolos , M. caobangensis , M. caudoprocta , M. cheni , M. chuannanensis , M. damrei , M. daweimontis , M. dongguanensis , M. dringi , M. elfina , M. fansipanensis , M. feae , M. feii , M. flavipunctata , M. gerti , M. gigantica , M. glandulosa , M. hansi , M. hoanglienensis , M. huangshanensis , M. insularis , M. jiangi , M. jinggangensis , M. jiulianensis , M. kalimantanensis , M. koui , M. kuatunensis , M. lancip , M. leishanensis , M. lekaguli , M. liboensis , M. lini , M. lishuiensis , M. longipes , M. major , M. mangshanensis , M. medogensis , M. medogensis , M. megacephala , M. microstoma , M. minor , M. mufumontana , M. nankiangensis , M. nankunensis , M. nanlingensis , M. obesa , M. ombrophila , M. omeimontis , M. oropedion , M. pachyproctus , M. parva , M. periosa , M. robusta , M. rubrimera , M. serchhipii , M. shunhuangensis , M. takensis , M. tuberogranulata , M. vegrandis , M. wawuensis , M. wugongensis , M. wuliangshanensis , M. wushanensis , M. xianjuensis , and M. zhangi (vs. with rudimentary or without webs).

By heels overlapping when thighs are positioned at right angles to the body, Megophrys qianbeiensis sp. nov. differs from M. acuta , M. brachykolos , M. dongguanensis , M. huangshanensis , M. kuatunensis , M. nankunensis , M. obesa , M. ombrophila , and M. wugongensis (vs. not meeting).

By the tibiotarsal articulation reaching to the level between tympanum and eye when leg stretched forward, Megophrys qianbeiensis sp. nov. differs from M. daweimontis , M. glandulosa , M. lini , M. major , M. medogensis , and M. obesa (vs. reaching the anterior corner of the eye or beyond eye or nostril and tip of snout).

By having an internal single subgular vocal sac in male, Megophrys qianbeiensis sp. nov. differs from M. caudoprocta , M. shapingensis , and M. shuichengensis (vs. vocal sac absent).

The congeners M. carinense and M. jiangi have sympatric distribution with Megophrys qianbeiensis sp. nov. ( Fei et al. 2012). The new species can be distinguished from these species by a series of morphological characters as follows. The new species differs from M. carinense in the smaller body size in the new species (adult males with 49.3-58.2 mm vs. adult males with 92-123 mm in the latter), a horn-like tubercle at the edge of each upper eyelid absent (vs. prominent in the latter), the tongue feebly notched behind (vs. notched behind in the latter). The new species differs from M. jiangi by a larger body size (49.3-58.2 mm in males in the new species vs. 34.4-39.2 mm in the latter), a horn-like tubercle at the edge of each upper eyelid absent (vs. present in the latter), the tongue feebly notched behind (vs. notched behind in the latter), presence of wide lateral fringes on the toes (vs. lacking in the latter), and toes with one-third webbing (vs. rudimentary webbing in the latter).

Megophrys qianbeiensis sp. nov. is phylogenetically closest to M. sangzhiensis and M. spinata . The new species differs from M. sangzhiensis by the following characters: horn-like tubercle absent at the edge of each upper eyelid (vs. present in the latter), toes with one-third webs (vs. with rudimentary webbing in the latter), vomerine ridges present distinctly as V-shape and vomerine teeth present (vs. vomerine ridges separated and weak, vomerine teeth absent in the latter), tibiotarsal articulation reaching to the level between tympanum and eye when leg stretched forward (vs. reaching the anterior corner of eye in the latter), spines on nuptial pads on the first two fingers larger and sparser (vs. finer and thicker in the latter), and having significantly higher ratios of HDL, LAL, HLL, TL, and IAE to SVL. On bioacoustics, the new species differs from M. sangzhiensis in the following characters: lower dominant frequency (2250-3000 Hz in the new species vs. 10380 - 13200 Hz in the latter), the amplitude beginning with moderately high energy pulses, increasing slightly to a maximum by approximately mid note, and then decreasing towards the end of each note (vs. beginning with maximum energy pulses and then decreasing towards the end of note in the latter).

The new species differs from M. spinata by the following characters: tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward (vs. reaching the anterior corner of eye in the latter), present distinctly as V-shape and vomerine teeth present (vs. vomerine ridges separated and weak, vomerine teeth absent in the latter), spines on nuptial pads on the first two fingers little weaker (vs. spines larger in the latter), and having significantly higher ratios of HDW, ED, LAL, TYD and IAE to SVL. On bioacoustics, the new species differs from M. spinata in the following characters: lower dominant frequency (2250-3000 Hz in the new species vs. 4260-4589 Hz in the latter), the amplitude beginning with moderately high energy pulses, increasing slightly to a maximum by approximately mid note, and then decreasing towards the end of each note (vs. beginning with lower energy pulses, then increasing to the maximum by approximately one-four note and then decreasing to the mid note then increasing to the second highest energy pulses and then decreasing towards the end of note in the latter).

Distribution and habitats.

Megophrys qianbeiensis sp. nov. is known from Huanglian Nature Reserve, Tongzi County and Kuankuoshui National Nature Reserve, Suiyang County, Guizhou Province, China at elevations between 1400-1600 m. The individuals of the new species were frequently found on stone in the streams surrounded by evergreen broadleaved forests (Fig. 8 ), and three sympatric amphibian species were found, i.e., Megophrys jiangi , Odorrana margaratae (Liu, 1950), and Zhangixalus omeimontis (Stejneger, 1924).

Etymology.

The specific epithet qianbeiensis refers to northern part of Guizhou, also called “黔”, the province where the type locality of the species belongs to. We propose the common English name "Qianbei horned toad" and Chinese name "Qian Bei Jiao Chan ( 黔北角蟾)”.

Figures

Figure 4. Visualization of advertisement calls of Megophrys qianbeiensis sp. nov., M. sangzhiensis, and M. spinata A 1 waveform showing one note of Megophrys qianbeiensis sp. nov. A 2 sonogram showing one note of Megophrys qianbeiensis sp. nov. A 3 waveform showing 25 notes of one call of Megophrys qianbeiensis sp. nov. A 4 sonogram showing 25 notes of one call of Megophrys qianbeiensis sp. nov. B 1 waveform showing one note of M. sangzhiensis B 2 sonogram showing one note of M. sangzhiensis B 3 waveform showing 38 notes of one call of M. sangzhiensis. B 4 sonogram showing 38 notes of one call of M. sangzhiensis C 1 waveform showing one note of M. spinata C 2 sonogram showing one note of M. spinata C 3 waveform showing 20 notes of one call of M. spinata C 4 sonogram showing 20 notes of one call of M. spinata.

Figure 5. Photos of the holotype CIBTZ 20190608017 of Megophrys qianbeiensis sp. nov. in life A dorsal view B ventral view C dorsal view of hand D ventral view of hand E ventral view of foot.

Figure 6. Photos of specimens of Megophrys qianbeiensis sp. nov., M. sangzhiensis and M. spinata A 1 - A 6 dorsal view, ventral view, dorsal view of hand, ventral view of hand, ventral view of foot and view of oral cavity of the holotype specimen CIBTZ 20190608017 of Megophrys qianbeiensis sp. nov. B 1 - B 6 dorsal view, ventral view, dorsal view of hand, ventral view of hand, ventral view of foot and view of oral cavity of CIBSZ 2012062005 of M. sangzhiensis C 1 - C 6 dorsal view, ventral view, dorsal view of hand, ventral view of hand, ventral view of foot and view of oral cavity of CIBLS 20190801001 of M. spinata. Arrow point to vomerine ridge.

Figure 7. Color variation in Megophrys qianbeiensis sp. nov. A dorsolateral view of the specimen CIBTZ 20160715003 B dorsolateral view of the specimen CIBTZ 20190608015 C ventral view of the male specimen CIBTZ 20190608015 D ventral view of the specimen CIBKKS 20180722001.

Figure 8. Habitats of Megophrys qianbeiensis sp. nov. in the type locality, Huanglian Nature Reserve, Tongzi County, Guizhou Province, China A landscape of montane forests in the type locality B a mountain stream where toads of the new species live (insert the holotype CIBTZ 20190608017 standing on the stone).