A large mantellid frog species: males 26-28 mm, females 34 mm. Dorsum very granular, brown with black markings. Ventrally brown with grey marbling. Males with tibial gland.
Similar species: Gephyromantis ventrimaculatus differs by its larger tympanum (1/2 of eye diameter). Gephyromantis malagasius is smaller and has longer hindlimbs.
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Madagascar
Tsaratanana (Manarikoba forest, Antsahamanintsy), Montagne d’ Ambre, Nosy Be, northern Madagascar.
Observed at elevations between 300-1400 m (Andreone and Glaw 2008).
Life History, Abundance, Activity, and Special Behaviors
Males call at night in the rainforest from the vegetation 50-150 cm above the ground. The calls are unharmonious notes, each consisting of 16-33 very widely spaced pulses.
Trends and Threats
This species has been listed as Endangered because its Extent of Occurrence is less than 5,000 km2, its distribution is severely fragmented, and there is continuing decline in the extent and quality of its habitat in northern Madagascar. It has been found in at least two protected areas in Madagascar: the Réserve Naturelle Intégrale du Tsaratanana and Parc National de Montagne d'Ambre (Andreone and Glaw 2008). It is now listed as Vulnerable (IUCN 2021).
Possible reasons for amphibian decline
General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Intensified agriculture or grazing
Account taken with permission from Glaw and Vences (2007).
Andreone, F. and Glaw, F. (2008). Gephyromantis horridus. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. www.iucnredlist.org. Downloaded on 18 March 2009.
Glaw, F., and Vences, M. (2007). Field Guide to the Amphibians and Reptiles of Madagascar. Third Edition. Vences and Glaw Verlag, Köln.
Originally submitted by: Miguel Vences and Frank Glaw (first posted 2000-11-27)
Edited by: Catherine Aguilar, Michelle S. Koo (2021-12-21)
Species Account Citation: AmphibiaWeb 2021 Gephyromantis horridus: Boettger's Grainy Frog <https://amphibiaweb.org/species/4604> University of California, Berkeley, CA, USA. Accessed Sep 29, 2022.
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Citation: AmphibiaWeb. 2022. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 29 Sep 2022.
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