Shrub frog (Philautus acutirostris)

Description

What’s the World’s Favourite Species?

Shrub frog fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Shrub frog description

Named due to its frequent presence on the branches and leaves of bushes and small trees, this shrub frog (Philautus acutirostris) is characterised by its pointed snout, partially webbed feet and rough or granular belly ⁽⁴⁾, a feature of many arboreal frogs thought to help increase water absorption ⁽⁵⁾.

The tiny body of Philautus acutirostris is brown, green and grey, and can display a wide variety of patterns ⁽⁶⁾. Typically though, it is a brownish colour ⁽²⁾, marked with small pale dots on the sides and limbs ^{(3) (6)}. In contrast, the underside is a creamy ivory colour with variable brown blotches ⁽⁶⁾.

Synonyms

Philautus basilanensis, Philautus woodi.

Size

Male snout-vent length: 16 - 23 mm ⁽²⁾

Female snout-vent length: 22 - 28 mm ⁽²⁾

Forelimb length: 15 mm ⁽³⁾

Hindlimb length: 40 mm ⁽³⁾

Shrub frog biology

Although the genus Philautus was discovered in 1822, knowledge of these frogs is still fairly limited due to their small size and great variety of colours ⁽⁴⁾. Male Philautus frogs typically have internal vocal sacs ⁽⁶⁾ and the euphonious tinkling sound, which is characteristic of these tiny green and brown frogs, is most often heard during the rainy season ⁽⁷⁾.

Philautus acutirostris has a very unique method of reproduction, as it exhibits direct development. That is, the eggs develop straight into froglets, typically having no aquatic tadpole stage ⁽⁴⁾. Following copulation, the female shrub frog produces a clutch of 10 to 20 eggs ⁽²⁾. The eggs are usually laid on the ground, under stones or dead leaves, or on the leaves of a fern, small shrub, or tree ⁽⁴⁾. Such plants are thought to typically include the wild banana plant and epiphytic ferns ⁽²⁾.

Shrub frog range

Philautus acutirostris is endemic to the Philippines and is found on the islands of Basilan, Jolo and the easternmost island Mindanao ⁽¹⁾.

On Mindanao, its natural distribution encompasses Dapitan peak on the Zamboanga Peninsula and Mount Hilonghilong ⁽²⁾.

Shrub frog habitat

Philautus acutirostris is a rainforest inhabitant and, although occasionally terrestrial, it usually adopts an arboreal lifestyle ⁽¹⁾. It is found from elevations of approximately 400 metres in dipterocarp forest to more than 2,000 metres in montane forest ⁽²⁾. At times it can be found quite far from any body of free water ⁽⁷⁾.

Shrub frog status

Philautus acutirostris is classified as Vulnerable (VU) on the IUCN Red List ⁽¹⁾.

Shrub frog threats

The major threat to Philautus acutirostris is the continued loss of lower montane forest and lowland rainforest habitat due to expanding agricultural plantations, mining activities, quarrying, logging, and human settlements ⁽¹⁾.

Shrub frog conservation

Some populations of Philautus acutirostris occur within protected National Parks. However, there is currently a need to improve the protection of additional habitats, particularly on the island of Mindanao, to prevent further population declines ⁽¹⁾.

Find out more

Find out more about the shrub frog and its conservation:

• Amphibia Web:
  http://www.amphibiaweb.org/
• IUCN/SSC Amphibian Specialist Group:
  http://www.amphibians.org/ASG/Home.html
• HERPWATCH Philippines:
  http://www.herpwatch.org/

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

This species information was authored as part of the ARKive and Universities Scheme.

Glossary

Arboreal

An animal which lives or spends a large amount of time in trees.

Dipterocarp

Trees of the family Dipterocarpaceae: resinous trees that are found in the old world tropics.

Endemic

A species or taxonomic group that is only found in one particular country or geographic area.

Epiphytic

A plant that grows on another plant, typically a tree, using it for physical support but not drawing nourishment from it.

Genus

A category used in taxonomy, which is below ‘family’ and above ‘species’. A genus tends to contain species that have characteristics in common. The genus forms the first part of a ‘binomial’ Latin species name; the second part is the specific name.

Montane forest

Forest occurring in the montane zone, a zone of cool upland slopes below the tree line.

References

1. IUCN Red List (July, 2011)
   http://www.iucnredlist.org/
2. Brown, W.C. and Alcala, A.C. (1994) Philippine frogs of the family Rhacophoridae. Proceedings of the California Academy of Sciences, 48: 185-220.
3. Taylor, E.H. (1920) Philippine Amphibia.Philippine Journal of Science, 16: 213-359.
4. Bossuyt, F. and Dubois, A. (2001). A review of the frog genus Philautus Gistel, 1848 (Amphibia, Anura, Ranidae, Rhacophorinae). Zeylanica, 6: 1-112.
5. Duellman, W.E. and Trueb, L. (1994) Biology of Amphibians. The Johns Hopkins University Press, Maryland.
6. Inger, R.F. (1954) Systematics and zoogeography of Philippine Amphibia. Fieldiana: Zoology, 33: 183-531.
7. Liem, S. (1970). The morphology, systematics, and evolution of the Old Worldtree frogs (Rhacophoridae and Hyperoliidae).Fieldiana: Zoology, 57: 1-145.