Microhyla
Microhyla, commonly known as the rice frogs or narrow-mouthed frogs, is a genus of frogs in the family Microhylidae. It consists of 42 species of diminutive frogs. Members of this genus are widespread from Ryukyu Is. in Japan, and throughout South-east Asia, (China, Sumatra, Java, Bali, Borneo, India and Sri Lanka). Taxonomy. In 2021, nine species of "Microhyla" were moved to "Nanohyla" on the basis of morphological and phylogenetic differences. "Microhyla pulverata" was found to be a junior synonym of "Nanohyla marmorata" based on phylogenetic evidence. Diagnosis. According to Seshadri et al. (2016), this genus can be  diagnosed using the following set of criteria: Adult frogs are of small size; pupil circular; skin on dorsum smooth; lateral side of body with markings from back of eye to vent; supratympanic fold present in adults; paratoid glands are absent, fingers without webbing, finger tips may or may not be dilated; oval tongue, its margin is entire and free at the base; the diameter of eye is smaller than snout; a thin layer of skin hides the tympanum; tubercles on hand distinct; distinct oval shaped inner metatarsal tubercle and rounded outer metatarsal tubercle; webbing in feet, rudimentary. Evolutionary relationships. The  genus "Microhyla" is closely related to "Glyphoglossus" within the family Microhylidae. Members of the genus "Microhyla" began diversifying from the most common ancestor around 45 million years ago and this resulted in forming "Metaphrynella" and "Microhyla". However, ascertaining the phylogenetic relationship of frogs within "Microhyla" has been difficult as many species are not monophyletic. A 2021 study on the relationship between "Microhyla" and "Glyphoglossus" found that nine species within "Microhyla" actually belong to a separate lineage. They have been subsequently moved to the new genus, "Nanohyla". Species. The following species are recognised in the genus "Microhyla": In central Vietnam, several  new species of "Microhyla" have been described in the 2000s: Several new species of "Microhyla" have been described since 2018. Phylogeny. The following phylogeny of the genus "Microhyla" is from Khatiwada, et al. (2017). 27 species are listed, including various newly described species from South Asia.