AmphibiaWeb - Bombinatoridae


(Translations may not be accurate.)


10 species in 2 genera

Commonly Called Yellow-Bellied Toads, Fire-Bellied Toads, Flat-Headed Toads

Bombina variegata variegata
Photo by Boris I. Timofeev
(Click for family gallery)

This family is composed of the two genera Barbourula and Bombina. Barbourula is found in the Philippines and Borneo while Bombina occurs in Europe, Soviet Republics, China, Vietnam, and Korea. Species of Bombina are active during the day and have aposematic coloration ventrally. Bombina arch their bodies backward in an "unken reflex" when threatened, exposing their bright ventral colors and thus advertising their toxic skin secretions. (This defensive reflex is also found in some salamanders.) Barboroula species are not as colorful and are very secretive and active at night. These are small aquatic toads that lay eggs and vocalize during inhalation (unique among extant anurans).

The only known lungless frog is a bombinatorid, Barbourula kalimantanensis, the Bornean Flat-headed Frog. Respiration is via the skin since it lacks lungs entirely, and thus this aquatic species lives in cold, clear mountain streams of Borneo with high oxygen content.

Written by AmphibiaWeb

Notable Family Characteristics

  • Inhabits ponds, slow-moving waters, and associated submersive vegetation or rocky shores
  • Aquatic
  • Bombina has brightly colored venters, likely as a warning coloration
  • Most likely diurnal
  • Displays "unken reflex" when threatened (Bombina)
  • Vocalizes on inhalation
  • Morphological characters for this group are: 1) halves of sphenethmoid fused; 2) absence of palatines and paired frontoparietals in skull; 3) epipubic muscle absent; 4) pupil triangular or vertically elliptical; 5) expanded flange of quadratojugal; 6) presence of endochondral ossifications in the hyoid plate
  • Distribution limited to Europe, and also Asia, specifically southern China through the Korean Peninsula, Borneo and Philippines
Bombinatoridae Richness map

Cartography Credit: Zoe Yoo, UC Berkeley
Range maps sources: AmphibiaWeb, UC Berkeley, and IUCN RedList

Relevant Reference

Bickford, D., Iskandar, D., and Barlian, A. 2008. ''A lungless frog discovered on Borneo.'' Current Biology, 18, R374-R375.

Vitt, L. J., and J. P. Caldwell. 2013. Herpetology. An Introductory Biology of Amphibians and Reptiles. Fourth Edition. Amsterdam: Elsevier.

Genus Barbourula (2 species)
Barbourula busuangensis account photos no sound/video
Barbourula kalimantanensis account photos no sound/video

Genus Bombina (8 species)
Bombina bombina account photos no sound/video
Bombina fortinuptialis no account no photos no sound/video
Bombina lichuanensis no account no photos no sound/video
Bombina maxima no account photos no sound/video
Bombina microdeladigitora account photos no sound/video
Bombina orientalis account photos no sound/video
Bombina pachypus account photos no sound/video
Bombina variegata account photos no sound/video

Citation: AmphibiaWeb: Information on amphibian biology and conservation. [web application]. Berkeley, California: AmphibiaWeb. Available: (Accessed:

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