
Bufonidae (true toads) in the order Anura (frogs)
The eastern American toad is medium-sized and has a large, kidney-shaped gland called the parotoid gland behind each eye. The pupil of each eye is horizontal. This toad may be gray, greenish gray, or various shades of brown. The dark spots on the back may encircle 1–3 warts. The belly is white with dark gray mottling. The call is a sustained, high-pitched musical trill lasting 6–30 seconds.
Similar species: There are two subspecies of American toad in our state: The eastern American toad (Anaxyrus americanus americanus), described above, which generally lives in the northern half, and the dwarf American toad (A. americanus charlesmithi), which lives in the southern section. The latter is smaller (only about 2 inches, snout to vent) and more reddish brown, with fewer, smaller, or no dark spots on the back; belly is cream colored with a few dark gray spots on the breast.
Length (snout to vent): 2 to 3 inches. Females are generally larger than males.
This toad prefers rocky, wooded areas and often lives along the edge of hardwood forests. Individuals hide during the day under rocks where there is loose, moist dirt, or they burrow into a depression where dead leaves have accumulated. Like most toads, this species becomes active at dusk.
Eats earthworms and a wide variety of insects. They are well-known for consuming large numbers of insects, and in summer they often catch and eat insects that fall to the ground under outdoor lights.
Throughout the northern half of the state, but intergrades with and is replaced by the dwarf American toad subspecies in the southern half of the state.
Missouri’s most common toad. The scientific name used to be Bufo americanus, but researchers in 2006 showed convincingly that some of the species formerly grouped together in the genus Bufo were different enough to warrant being separated into different genera. That is why our toad is now named Anaxyrus americanus.
In our state, males begin calling on warm nights in late March and early April. Breeding occurs in small, temporary ponds in woodlands, in slow, shallow streams, or in water-filled ditches in late March, April, and early May. Eggs are laid in long, double strands. A female can lay 2,000–20,000 eggs, which hatch, in about a week, into tiny black tadpoles. These remain in water until early to mid-June, when they transform into tiny toadlets.
Contrary to superstition, toads do not cause warts on humans. They are harmless. Despite toads' complexion and dour countenance, many people find them endearing. During summer nights, toads help us by consuming insects and other small organisms that are pests or annoyances to us.
Toads are predators that help keep populations of insects and other small animals in balance. They, and especially their eggs, tadpoles, and young toadlets, become food for both aquatic and terrestrial predators ranging from water bugs to fish to grackles to raccoons.
Missouri’s herptiles comprise 43 amphibians and 75 reptiles. Amphibians, including salamanders, toads, and frogs, are vertebrate animals that spend at least part of their life cycle in water. They usually have moist skin, lack scales or claws, and are ectothermal (cold-blooded), so they do not produce their own body heat the way birds and mammals do. Reptiles, including turtles, lizards, and snakes, are also vertebrates, and most are ectothermal, but unlike amphibians, reptiles have dry skin with scales, the ones with legs have claws, and they do not have to live part of their lives in water.