APPEARANCE
From the name, one might expect this type of toad to look like, well, a leaf. This type of mimicry is an
example of cryptic coloration (compare aposematic
coloration), which serves to camouflage the animal. These toads likely have other defenses—most
amphibians have skin poisons—although less potent than the colorful poison frogs.
As members of the large amphibian genus Bufo, leaf toads share typical toad characteristics: short,
stocky body with short legs and a rounded body. In some leaf toads, the body may be more flattened than in
typical toads.
Most leaf toads are 2 to 3 inches in length and dull-colored, grayish green, with disruptive markings that
break up the outline of the body and blend in with the leaf litter leaves. Several species have
protuberances around the head and a light-colored thin dorsal stripe.
Note on taxonomy
The taxonomy of these toads is not well understood. Several
similar-looking species share the common name. From a scientific standpoint, herpetologist Bill
Lamar, an expert on Amazonian reptiles and amphibians, notes that most Amazonian leaf toads lack formal names
and that he has recorded at least seven unnamed ones in the forests around Iquitos. Taxonomists are debating
whether to reclassify the genus Bufo and perhaps to split it into two or more additional genera. Recent
DNA analyses have reinforced the idea that this group is polyphyletic (Pramuk 2006); that is, derived from two or more
ancestral groups. (This indicates that the genus is not a "natural" grouping.)
HABITAT AND DISTRIBUTION
Leaf toad species are widely distributed across tropical South America, into parts of Central America in most
frost-free areas. Their preferred habitat is rainforest among leaf litter on the forest floor in the ground
layer.
FEEDING AND DIET
Toads are generalist predators of insects and other invertebrates. Large species may take small mammals and
reptiles, but these food items are an exception.
BREEDING
Among most species in the genus Bufo, males are usually smaller than females. The adult males of
many species have a dark throat.
Bidder's organ is a spherical, brownish reproductive organ in male toads in the Bufonidae family. This
is an incompletely developed ovary located just in front of the kidney. In the mature male, the organ
serves no apparent purpose. However, if the toad's male glands are removed, Bidder's organ produces
egg cells and hormones that cause female organs to develop.
For more information on the genus Bufo, see cane toad natural
history.
CONSERVATION
The leaf toad is common. One name is the South American common toad. However, as mentioned above, the numbers and types of different species are uncertain in most cases, so
some species may be more at risk than others. Since this toad requires moist forested habitat
ongoing habitat destruction is likely to reduce populations.
REFERENCE
Pramuk, J.B. (2006) Phylogeny of South American Bufo (Anura: Bufonidae) inferred from combined
evidence. J. Linnean Society 146: 407-452
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