Morphology, molecular genetics, and acoustics reveal two new species of the genus Leptobrachella from northwestern Guizhou Province, China (Anura, Megophryidae)

Acoustic difference in advertisement calls among two sympatric Boulenophrys species: A confirmatory case to acoustic niche hypothesis and morphological constraint hypothesis

In anurans, acoustic communication is the most important form of communication at the interspecific and intraspecific levels. Acoustic diagnostic features may be a potential alternative to morphometric and molecular diagnostics. Here, we assessed the variations in advertisement calls between two sympatric species, Boulenophrys leishanensis and Boulenophrys spinata, that share their breeding season and breeding sites. In addition, we investigated any potential relationships between call parameters and body size. We found that the advertisement calls of both species are simple calls. The two species exhibited significant differences in all call parameters. Both B. leishanensis and B. spinata showed a significant negative correlation with their body size on dominant frequency. These differences in call parameters may play an important role in interspecific recognition. Additionally, because intraspecific acoustic variation reflects body size, calls may be relevant for sexual selection. Our study supports the acoustic niche hypothesis and the morphological constraint hypothesis and calls are a valid tool for distinguishing between the two species of Boulenophrys in the field.

Description of a new Asian Leaf Litter Toad of the genus Leptobrachella Smith, 1925 (Anura, Megophryidae) from southern Guizhou Province, China

Background

The Asian leaf litter toads of the genus Leptobrachella Smith, 1925 (Anura, Megophryidae) inhabit the forest floor and rocky streams in hilly evergreen forests and are widely distributed from southern China, west to north-eastern India and Myanmar, through mainland Indochina to Peninsular Malaysia and the Island of Borneo.

New information

A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described. Molecular phylogenetic analyses, based on mitochondrial 16S rRNA and COI genes and nuclear RAG1 gene sequences indicated that the new species is genetically divergent from its congeners. The new species could be distinguished from its congeners by a combination of the following characters: (1) body of medium size in males (SVL 31.9 - 32.9 mm); (2) distinct black spots present on flanks; (3) toes rudimentarily webbed, with wide lateral fringes; (4) skin on dorsum shagreened with fine tiny granules and short ridges; (5) heels overlapped when thighs are positioned at right angles to the body; (6) tibia-tarsal articulation reaching interior corner of the eye.A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described. Molecular phylogenetic analyses, based on mitochondrial 16S rRNA and COI genes and nuclear RAG1 gene sequences indicated that the new species is genetically divergent from its congeners. The new species could be distinguished from its congeners by a combination of the following characters: (1) body of medium size in males (SVL 31.9 - 32.9 mm); (2) distinct black spots present on flanks; (3) toes rudimentarily webbed, with wide lateral fringes; (4) skin on dorsum shagreened with fine tiny granules and short ridges; (5) heels overlapped when thighs are positioned at right angles to the body; (6) tibia-tarsal articulation reaching interior corner of the eye.

Two new species of Leptobrachella Smith 1925 (Amphibia: Megophryidae) from Cao Bang Province, Vietnam

Two new species, Leptobrachella phiaoacensis sp. nov. and Leptobrachella phiadenensis sp. nov., are described from Phia Oac-Phia Den National Park, Cao Bang Province, Vietnam based on genetic divergence and morphological differences. Leptobrachella phiaoacensis sp. nov. is characterized by a combination of the following characters: size medium (27.833.3 mm in five adult males and 31.541.8 mm in five adult females); head longer than wide; tympanum distinct; dorsal skin shagreened with fine tubercles; toes webbing rudimentary, with narrow lateral fringes; supratympanic fold edged by a distinct black line; the presence of a dark brown triangle in interorbital region and a W-shaped marking in scapular region; belly from pinkish white to white with dark brown specking on belly periphery; iris bicolored copper in upper part, fading to silvery grey in lower part. Leptobrachella phiadenensis sp. nov. is distinguished from its congeners by a combination of the following morphological characters: size medium (27.628.6 mm in two adult females); head wider than long; tympanum distinct; skin on dorsal head and body rough with warts, tubercles and dermal ridges; toes webbing rudimentary, with narrow dermal fringes; supratympanic fold orange; dorsal surface of head and body with some large dark brown markings, a dark brown triangle in interorbital region, edged in white; flank light brown with some dark flecks; belly white with dark specking on outer margins; iris bicolored, copper in upper part, fading to silvery grey in lower part. In terms of genetic distance, the two new species differ from each other and other congeners for which comparable sequences are available by at least 3.7% (16S rRNA gene). Recognition of these new species brings the total number of known species in the genus Leptobrachella from Vietnam to 34.

A new Asian leaf litter toad of the genus Leptobrachella (Amphibia, Anura, Megophryidae) from central south China

A new species of the Asian leaf litter toad genus Leptobrachella from central south China is described. Molecular phylogenetic analyses, based on mitochondrial 16S rRNA and nuclear RAG1 gene sequences indicated the new species as an independent clade in the genus. The new species could be distinguished from its congeners by a combination of the following characters: body of medium size (SVL 29.2–34.2 mm in 15 adult males and 34.4–43.1 mm in seven adult females); distinct black spots present on flanks; toes rudimentary webbed, with wide lateral fringes; ventral belly white with distinct nebulous brown speckling on ventrolateral flanks; skin on dorsum shagreened with fine tiny granules or short ridges; iris copper above, silver below; heels overlapped when thighs are positioned at right angles to the body; tibia-tarsal articulation reaches the middle eye; dorsal surface of tadpole semi-transparent light brown, spots on tail absent, keratodont row formula I: 3+3/2+2: I; call series basically consist of repeated long calls, at dominant frequency (5093 ± 412 Hz).

A new species of the genus Leptobrachella (Anura, Megophryidae) from northwestern Guangdong Province, China

The genus Leptobrachella is a species-rich genus of megophrid frog. Rapid discovery of many new species within this genus emphasizes the importance of regional research. In this study, we describe a new species of Leptobrachella, Leptobrachella verrucosasp. nov., from northwestern Guangdong Province, China, based on a combination of molecular and morphological data. A key including congeners from the same province, namely L. laui, L. liui, L. mangshanensis, L. shimentaina, and L. yunkaiensis, is provided.

A new Leptobrachella species (Anura, Megophryidae) from South China, with comments on the taxonomic status of L. chishuiensis and L. purpurus

A new species of Leaf Litter Toad, Leptobrachella shimentainasp. nov., is described from the Shimentai and Luokeng nature reserves of northern Guangdong Province, southern China. The new taxon can be distinguished from all recognized congeners by a combination of discrete morphological character state differences relating to its small body size (SVL 26.4–28.9 mm in six adult males, 30.1 and 30.7 mm in two adult females); a number of apparently fixed color pattern character differences (including eye coloration and color pattern features from dorsal, ventral, and dorsolateral surfaces of its head, body, limbs, and ventrum); the morphological and discrete characteristics of the external phenotype (the skin texture of dorsum and ventrum, the presence of supra-axillary and ventrolateral glands, the wide dermal fringes and rudimentary webbing on toes, and the uninterrupted longitudinal ridges under toes). Two samples of this new species previously were proposed as representing a new, unnamed species. We now substantiate this claim by providing diagnostic comparisons of discrete character differences. In addition, we also discuss taxonomic uncertainty surrounding the identity of two congeners, L. chishuiensis and L. purpurus, which we interpret as indicative of taxonomic inflation in the species-rich subfamily Megophryidae.

A new species of Leptobrachella (Anura, Megophryidae) from Mount Pu Ta Leng, northwest Vietnam

The Hoang Lien Range in northwest Vietnam is known to harbour five species of Leptobrachella, a specious genus of terrestrial frogs. We collected specimens of Leptobrachella from Mount Pu Ta Leng on the second highest peak in the Hoang Lien Range and use morphological and molecular data to show that this population represents a previously undescribed species which we name Leptobrachella graminicola sp. nov. after the abundance of calling males on sedge-like plants. This new species is closely related to L. bourreti but the new species is distinguished from L. bourreti and other congeneric species by a combination of the following characters: (1) a body size range of 23.124.6 mm in six adult males and 28.632.9 mm in five adult females; (2) skin on dorsum smooth, with many tubercles and lacking dermal ridges; (3) toes with rudimentary webbing and broad lateral fringes; (4) belly white with brown spots; (5) throat dark brown with light grey-brown flecks and spots; (6) a row of large white spots on the outer edge of the tarsus extending from the heel to the inner metatarsal tubercle, sometimes forming a long white stripe; and (7) a bicoloured iris. The new, high-elevation species is likely to be range-restricted and threatened by habitat loss and the activities of tourists.

A species of the genus Panophrys (Anura, Megophryidae) from southeastern Guizhou Province, China

Herein, we describe Panophryscongjiangensissp. nov. obtained from the Yueliangshan Nature Reserve, Congjiang County, Guizhou Province, China. Phylogenetic analyses based on the mitochondrial genes 16S rRNA and COI indicated that this new species represented an independent lineage, closely related to P.leishanensis. The uncorrected genetic distances between the new species and its closest congener, P.leishanensis, were 3.0% for 16S rRNA and 8.4% for COI. The new species is distinguished from its congeners by a combination of the following morphological characteristics (1) medium body size (SVL 28.6–33.4 mm in males and 38.4–40.2 mm in females); (2) a small horn-like tubercle at the edge of each upper eyelid; (3) the tympanum distinctly visible (TD/ED ratio 0.47–0.66); (4) vomerine teeth absent; (5) the tongue not notched behind; (6) a narrow and unobvious lateral fringe on toes; (7) relative finger lengths II < I < V < III; (8) rudimentary webs on toes; (9) hindlimbs slender, heels overlapping when thighs are positioned at right angles to the body; (10) two metacarpal tubercles on the palm, with the inner metatarsal tubercle long and oval-shaped; (11) the tibiotarsal articulation reaching the nostril when the leg is adpressed and stretched forward; (12) dorsal skin rough with numerous orange–red granules, ventral surface smooth; (13) a single internal subgular vocal sac present in males; and (14) in breeding males, weak gray-black nuptial pads with black nuptial spines present on the dorsal surface of the bases of the first and second fingers. To date, the new species is only known from the type locality.

A new species of the Asian leaf litter toad genus Leptobrachella Smith, 1925 (Anura, Megophryidae) from northwest Guizhou Province, China

A new species of the Asian leaf litter toad genus Leptobrachella is described from Guizhou Province, China. Molecular phylogenetic analyses support the new species as an independent lineage deeply nested in the Leptobrachella clade. The new species is distinguished from its congeners by a combination of the following morphological characters: body size medium (SVL 29.7–31.2 mm in five adult males); dorsal skin shagreened, some of the granules forming longitudinal short skin ridges; tympanum distinctly discernible, slightly concave; supra-axillary, femoral, pectoral and ventrolateral glands distinctly visible; absence of webbing and lateral fringes on fingers; toes with narrow lateral fringes but without webbing; heels overlapping when thighs are positioned at right angles to the body; tibia-tarsal articulation reaching the middle of eye when leg stretched forward. The discovery highlighted the underestimated species diversity in the Leptobrachella toads in southwestern China.

A new species of the genus Leptobrachella Smith, 1925 (Anura, Megophryidae) from Guizhou, China

Asian leaf-litter toads of the genus Leptobrachella represent charismatic anuran diversification with 80 species, of which 25 are from China. Recent new discoveries suggest that the diversity of this genus is underestimated. Here, we describe a new species of Leptobrachella, Leptobrachella bashaensis sp. nov. from the Basha Nature Reserve, Congjiang County, Guizhou Province, China. The new species is distinguished from its congeners by the following suite of morphological traits: small body size (SVL 22.9-25.6 mm in six adult males and 27.1 mm in one adult female); head longer than wide; dorsal skin slightly shagreened with small tubercles; creamy-white chest and belly with irregular black spots; distinct ventrolateral glands forming a white line; finger webbing and fringes absent; toe webbing rudimentary and lateral fringes narrow; iris bicolored with bright orange in upper half and silver in lower half; dorsal surface of tadpole head dark brown with small, brown, irregular spot, air sac-shaped bulges on both sides of body. The new species differs from all known congeners by an uncorrected p-distance of >5.3% of the 16S rRNA gene fragment examined, and the phylogenetic analysis clusters the new species with L. maoershanensis and L. laui. At present, the new species is only known from a small range of montane evergreen secondary forests in Basha Nature Reserve approximately 900 m elevation. Its natural history and conservation status are discussed.

Description of a new horned toad of Megophrys Kuhl & Van Hasselt, 1822 (Amphibia, Megophryidae) from Zhejiang Province, China

A new species of the Asian horned toad genus Megophrys is described from Zhejiang Province, China, based on multiple data. Molecular phylogenetic analyses based on mitochondrial DNA indicated the new species as an independent clade deeply clustered into the Megophrys clade. The new species is identified from its congeners by a combination of the following characters: body size small (SVL 28.4-32.4 mm in males); vomerine teeth absent; tongue not notched behind; tympanum distinctly visible, oval; a small horn-like tubercle present at the edge of each upper eyelid; two metacarpal tubercles distinctly visible in hand; toes without webbing; heels overlapped when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level to middle of eye when leg stretched forward; an internal single subgular vocal sac in male; in breeding male, the nuptial pads present on the dorsal base of the first two fingers.

Two new Leptobrachella species (Anura, Megophryidae) from the Yunnan-Guizhou Plateau, southwestern China

Two new toad species of the genus Leptobrachella are described from the Yunnan-Guizhou Plateau of China, based on the combination of molecular and morphological data. The description of Leptobrachellaaspera Wang, Lyu, Qi & Wang, sp. nov. from Huanglianshan Nature Reserve represents the thirteenth Leptobrachella species known from Yunnan Province, and the description of Leptobrachelladorsospina Wang, Lyu, Qi & Wang, sp. nov. from Yushe Forest Park represents the sixth Leptobrachella species known from Guizhou Province. These new discoveries further emphasize the extremely high diversity of the Leptobrachella toads in these regions.

Description of a new Megophrys Kuhl & Van Hasselt, 1822 (Anura, Megophryidae) from Guizhou Province, China

A new species of the genus Megophrys is described from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA indicated the new species as a clade clustered into the Megophrys clade. The new species can be distinguished from its congeners by a combination of the following characters: body size moderate (SVL 40.0-45.5 mm in males and 48.9-51.2 mm in females); vomerine teeth absent; tongue not notched behind; tympanum distinctly visible, oval; a small horn-like tubercle at the edge of each upper eyelid; two metacarpal tubercles in hand; toes with rudimentary webbing; heels overlapping when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level of mid-eye when leg stretched forward; in breeding males, an internal single subgular vocal sac present and brownish nuptial pads, made up of black nuptial spines, present on the dorsal base of the first two fingers.

How little is known about "the little brown frogs": description of three new species of the genus Leptobrachella (Anura: Megophryidae) from Yunnan Province, China

Asian leaf-litter toads of the genus Leptobrachella represent a great anuran diversification in Asia. Previous studies have suggested that the diversity of this genus is still underestimated. During herpetological surveys from 2013 to 2018, a series of Leptobrachella specimens were collected from the international border areas in the southern and western parts of Yunnan Province, China. Subsequent analyses based on morphological and molecular data revealed three distinct and previously unknown lineages, which we formally describe as three new species herein. Among them, we describe a new species that occurs at the highest known elevation for Leptobrachella in China. Four species of Leptobrachella, including two new species, are found in the same reserve. Furthermore, our results suggest that the population from Longchuan County, Yunnan, may represent an additional new species of Leptobrachella, although we tentatively assigned it to Leptobrachella cf. yingjiangensis due to the small sample size examined. Lastly, we provide the first description of females of L. yingjiangensis. Our results further highlight that both micro-endemism and sympatric distributions of species are common patterns in Leptobrachella, that contribute to taxonomic and conservation challenges in these frogs. We provide an identification key for Leptobrachella known to occur in Yunnan. Given the lack of knowledge on species diversity of Leptobrachella along international border areas, we recommend that future studies include trans-boundary collaborative surveys.

Description of a new horned toad of Megophrys Kuhl & Van Hasselt, 1822 (Anura, Megophryidae) from southwest China

A new species of the genus Megophrys is described from Guizhou Province, China. Molecular phylogenetic analyses supported the new species as an independent clade nested into the Megophrys. The new species could be distinguished from its congeners by a combination of the following 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.

A new species of the Asian leaf litter toad genus Leptobrachella (Amphibia, Anura, Megophryidae) from southwest China

A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described based on molecular phylogenetic analyses, morphological comparisons, and bioacoustics data. Phylogenetic analyses based on the mitochondrial 16S rRNA gene sequences supported the new species as an independent clade nested into the Leptobrachella clade and sister to L.bijie. The new species could be distinguished from its congeners by a combination of the following characters: small body size (SVL 30.8–33.4 mm in seven adult males, and 34.2 mm in one adult female); dorsal skin shagreened, some of the granules forming longitudinal short skin ridges; tympanum distinctly discernible, slightly concave; internasal distance longer than interorbital distance; supra-axillary, femoral, pectoral and ventrolateral glands distinctly visible; absence of webbing and lateral fringes on fingers; toes with rudimentary webbing and shallow lateral fringes, relative finger lengths II < IV < I < III; heels overlapped when thighs are positioned at right angles to the body; and tibia-tarsal articulation reaches the tympanum.

A new species of Leptobrachella (Anura, Megophryidae) from Guizhou Province, China

This study describes a new species of the genus Leptobrachella, Leptobrachellasuiyangensissp. nov. from the Huoqiuba Nature Reserve, Suiyang County, Guizhou Province, China, based on morphological data and phylogenetic analyses (16S rRNA mtDNA). The new species can be distinguished from other congeners by the molecular divergence and by a combination of morphological characters, including body size, dorsal and ventral patterns, dorsal skin texture, size of the pectoral and femoral glands, degree of webbing and fringing on the toes and fingers, dorsum coloration, and iris coloration in life. Currently, the genus Leptobrachella contains 75 species, 21 of which are found in China, including seven species reported from Guizhou Province. The uncorrected sequence divergence percentage between Leptobrachellasuiyangensissp. nov. and all homologous DNA sequences available for the 16S rRNA gene was found to be >4.7%. The new record of the species and its relationships with others in the same genus imply that species distribution, habitat variation, environmental adaptation, and diversity of the genus Leptobrachella in southwest China need to be further investigated.

A new species of the Music frog Nidirana (Anura, Ranidae) from Guizhou Province, China

The Music frog genus Nidirana is widely distributed in East and South Asia. Here, a new species of the genus is described from southwestern China. Phylogenetic analyses based on the mitochondrial 16S rRNA and COI gene sequences supported the new species as a clade closely related to N. leishanensis, N. hainanensis, N. chapaensis, N. daunchina, and N. yaoica. The new species could be distinguished from its congeners by a combination of the following characters: body of medium size (SVL 41.2-43.5 mm in males and 44.7 mm in female); lateroventral groove only present on toes; relative finger lengths: II < IV < I < III; three metatarsal tubercles on palm; heels overlapping when hindlimbs flexed at right angles to axis of body; tibiotarsal articulation reaching the level of eye when leg stretched forward; a pair of subgular internal vocal sacs at corners of throat in male; nuptial pad present on the inner side of base of fingers I in breeding male; tadpole labial tooth row formula with 1:1+1/1+1:2; in males, the advertisement call contains two kinds of notes and one call contains 2-6 repeated regular notes.