''Liuixalus calcarius'', the limestone small tree frog, is a species of frog in the family

Rhacophoridae The Rhacophoridae are a family of frogs in tropical sub-Saharan Africa, South India and Sri Lanka, Japan, northeastern India to eastern China and Taiwan, south through the Philippines and Greater Sundas, and Sulawesi. They are commonly known as ...

. It is endemic to

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

, where it was found in Hai Phong Province. It lives in tropical

primary forest An old-growth forest or primary forest is a forest that has developed over a long period of time without Disturbance (ecology), disturbance. Due to this, old-growth forests exhibit unique ecological features. The Food and Agriculture Organizati ...

habitats rich in karst rock.

Description

The skin of the dorsum is red-brown in color with an X-shaped mark on the shoulder. This frog has disks on its toes for climbing. The pupil of the eye is horizontal.

Etymology

Scientists named this frog ''calcarius'' for the

Latin language Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

word for "limestone." The frog's habitat is rich in

karst Karst () is a topography formed from the dissolution of soluble carbonate rocks such as limestone and Dolomite (rock), dolomite. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. Ther ...

rock.

Habitat

This frog has been observed between 15 and 45 meters above sea level on

Cat Ba Island The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the do ...

. The frog has been found near pools of water in the karst rock and in small, temporary lakes that dry up for part of the year. Cat Ba Island is in Cat Ba National Park, and scientists believe the frog's range to be larger than this place alone.

Reproduction

Scientists have heard the male frogs calling in April but know little else about this species' reproductive biology. They infer that it breeds through larval development, like its congeners.

Threats

The IUCN classifies this frog as endangered. Scientists believe it to be forest-dependent, which would make it threatened by

deforestation Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...

associated with agriculture and logging.

References

Frogs of Asia Amphibians described in 2013 Endemic fauna of Vietnam Rhacophoridae {{Rhacophoridae-stub