''Leptolalax'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...

s ( order Anura) in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Megophryidae Megophryidae, commonly known as goose frogs, is a large family of frogs native to the warm southeast of Asia, from the Himalayan foothills eastwards, south to Indonesia and the Greater Sunda Islands in Maritime Southeast Asia, and extending to th ...

. They are sometimes known as Asian toads, metacarpal-tubercled toads, or slender litter frogs, although many species-specific common names do not follow these conventions, and many species do not have common names. They are widely distributed in southeastern and eastern

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

, from southern China and northeastern India to the

Malay Peninsula The Malay Peninsula (Malay: ''Semenanjung Tanah Melayu'') is a peninsula in Mainland Southeast Asia. The landmass runs approximately north–south, and at its terminus, it is the southernmost point of the Asian continental mainland. The area ...

and

Borneo Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...

. ''Leptolalax'' are typically small and have a cryptic colour pattern and no obvious morphological characters useful in systematic studies. Consequently, both molecular genetic analyses and analysis of advertisement calls by male frogs have been important in identifying new species. Leptolalax liui

Two

subgenera In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

are recognized: ''Leptolalax'' and ''Lalos'' (the latter was first named as ''Lalax'', but the name was already occupied). ''Lalos'' has a more northern distribution and only includes species from the continental Asia, whereas ''Leptolalax'' includes all the species from

(''

Leptolalax arayai ''Leptobrachella arayai'' is a species of frog in the family Megophryidae. It is endemic to Sabah, Malaysia. In addition to its type locality, Mount Kinabalu, it is known from Mount Trusmadi, Crocker Range, and Mendolog. Its natural habitats a ...

'', ''

Leptolalax dringi ''Leptolalax dringi'' (Dring's Asian toad) is a frog species in the family Megophryidae. It is endemic to Borneo and found in Kalimantan (Indonesia) and in Sarawak and Sabah (Malaysia). Its type locality is Mount Mulu in Gunung Mulu National Pa ...

'', ''

Leptolalax fritinniens ''Leptolalax fritinniens'' is a species of frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without t ...

'', ''

Leptolalax gracilis ''Leptolalax gracilis'' is a frog species in the family Megophryidae. It is endemic to northern Borneo: Brunei, Kalimantan (Indonesia), and Sarawak (Malaysia). Earlier record from the Malay Peninsula and Thailand refer to other species (at least ...

'', ''

Leptolalax hamidi ''Leptolalax hamidi'' is a frog species in the family Megophryidae. It is endemic to Borneo, where it can be found both in western Sarawak, Malaysia, and Kalimantan, Indonesia. Its natural habitats are tropical moist lowland hilly forests and ri ...

'', ''

Leptolalax maurus ''Leptolalax maurus'' is a frog species in the family Megophryidae. It is endemic to Borneo where it is only known from its type locality, Mount Kinabalu in Sabah, Malaysia. Its natural habitats are tropical moist montane forests and rivers. I ...

'', '' Leptolalax sabahmontanus'', '' Leptolalax marmoratus'' and '' Leptolalax pictus''A Field Guide to the Frogs of Borneo, Third Edition) as well as few continental species (''

Leptolalax croceus ''Leptolalax croceus'' (orange-bellied leaf-litter toad) is a species of toad in the family Megophryidae. Discovered in the Central Vietnam in 2010, it is endemic to the region as it is only known from its type locality, Ngoc Linh Nature Reser ...

'', ''

Leptolalax melicus ''Leptolalax melicus'' (Appleby's Asian toad; km, កង្កែបស្លឹកមេលីកឺស, ) is a frog species in the family Megophryidae. It is endemic to Cambodia Cambodia (; also Kampuchea ; km, កម្ពុជា, ...

'') and ''

Leptolalax kajangensis ''Leptobrachella kajangensis'', also known as the Kajang slender litter frog, is a species of amphibian in the family Megophryidae. It is endemic to Malaysia and only known from its type locality, a small cave near the top of Gunung Kajang (=M ...

'' from

Tioman Island Tioman Island ( ms, Pulau Tioman) is a mukim and an island in Rompin District, Pahang, Malaysia. It is located off the east coast of the state, and is some long and wide. It has seven villages, the largest and most populous being Kampung Te ...

, at least provisionally. Most ''Leptolalax'' species have been reported from very small areas and only a few species have large areas of occurrence. Whether this distinction is real or the widespread species represent

cryptic species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

es remains to be confirmed.

Species

In 2016, 50 species were known in the genus. New species are still being described, including three in 2013, four in 2014, one in 2015, and six in 2016:

References

{{Taxonbar, from=Q2379278 Amphibians of Asia Amphibian genera