Added as separate page 30 June 2006.

Frogs and Toads of Europe: Bombinatoridae, Fire-Bellied Toads

To look at them from above, the Fire-Bellied Toads appear rather small and nondescript little creatures. However, if you can view them from below, a different picture emerges: the belly is a bright red or orange. The toads use this as a defensive display in the so-called "unken reflex": if threatened, they display their bellies, whose vivid coloration will denote to most predators a distasteful or poisonous taste should they attempt to eat the owner.

The Family Bombinatoridae were formerly considered part of the Family Discoglossidae, and like them are an older group of frogs, belonging to the Archeobatrachia ("old" or "ancient" frogs). They have true ribs, unlike frogs and toads belonging to the Neobatrachia ("new" frogs).

In Europe they are represented by two species in the genus Bombina, which has several other species in Asia. Another small genus, Barbourula, is found in the Philippines and Indonesia.

NB Unlike the pages for the other Reptile and Amphibian families, where measurements were given in inches or feet, measurements for the families here are given in centimetres, owing to the generally small size of the subjects.

Either click on a frog or toad in the Quick Links section or scroll down for the whole table.

	QUICK INDEX
Bombina bombina, Fire-Bellied Toad	Bombina variegata, Yellow-Bellied Toad

Scientific Name	Common Name	Distribution	Size	Notes
European BOMBINATORIDAE
Bombina
B. bombina	Fire-Bellied Toad	Denmark east as far as R. Volga	4-5 cm	Despite the similarity between this and B. variegata, they are found at different altitudes, B. bombina being found primarily at low altitudes in still water (small pools, marsh waters, ponds and large lakes), where it frequents vegetation in or besides the water. It is a good diver and preys mainly on aquatic arthropods, including all stages of the mosquito. If the water source dries up, these toads can survive by sheltering in fissures in the mud and preying on terrestrial arthropods. Despite its large range, the Fire-Bellied Toad does not have any subspecies: nevetheless in some areas it overlaps with the Yellow-Bellied Toad, and sometimes hybrids are found. For such a small toad B. bombina is surprisingly vocal during the mating season (May-July): unlike the males of B. variegata, male Fire-Bellied Toads have a subcutaneous vocal sac, noticeable only when inflated. Colouring differs from that of the Yellow-Bellied Toad, not only in being red as opposed to yellow but also in the Fire-Bellied Toad having darker spots on its back and having a greater area of dark colouring on the abdomen. The shapes of the warts also differ between the two species: in B. variegatus they have small sharp rough spines, whereas in B. bombina they have blunt tough tips. Captive Fire-Bellied Toads have lived for up to 30 years.
B. variegata	Yellow-Bellied Toad	W & C. Europe, Italy N of Po, N Balkans and E Europe	5 cm	A small and seemingly inconspicuous toad found in pools on hills and moutains, Bombina variegata actually derives its common name from its underbelly, which it displays as a toxicity warning if threatened. Consistent with this is the secretion of venom from cutaneous gland which can cause stinging if contacting human mucous membranes. It is an aquatic toad and is found in pools and puddles as well as village ponds, where it can tolerate a high degree of natural organic contamination, eg from decaying leaves. In May-July females lay over 100 eggs: these hatch 12 days later, producing 6mm larvae. Larvae hatching later in the year do not metamorphose but enter hibernation in the larval stage. Adult toads hibernate in the ground.
B. v. variegata
B. v. kolombatovici		C & S Dalmatia as far as W Montenegro
B. v. pachypus		Italy S of the Po floodplain, NE Sicily
B. v. scabra		S. Balkans (Montenegro, Albania, Greece, Bulgaria; poss. Romania)

Bibliography

Collins Field Guide to Reptiles & Amphibians of Britain & Europe, E N Arnold, J A Burton and D W Ovenden, HarperCollins, London 1978. For years this has been an invaluable guide to the English speaker, although a few of the taxonomic details were in need of revision. This was finally accomplished with the revised edition of 2002/4.

Lurche und Kriechtiere Europas [Amphibians and Reptiles of Europe], Dr Wolf-Eberhard Engelmann, Jürgen Fritzsche, Dr sc. Rainer Günther and Dipl.Biol. Fritz Jürgen Obst, Ferdinand Enke Verlag, Stuttgart 1986. A German-language equivalent but with a rather wider definition of Europe which includes the Transcaucasus, and useful details on the distribution of subspecies. Now apparently out of print.

Die Amphibien Europas, Andreas and Christel Nöllert, Franckh-Kosmos, Stuttgart 1992. Outstanding nature guide to every species of amphibian found in Europe.