Lepidobatrachus laevis

Lepidobatrachus laevis photographed at Newport Aquarium

This frog has become popular in pet stores due to its comical flat appearance and intelligent behavior. Females reach a size of 100 millimetres (3.9 in) while males sometimes only grow half as large. They have a large head that makes up to 1/3 of the body, with a notably large mouth. Their mouth contains a top row of teeth and two "fangs" on the lower jaw. They have extremely short and stubby limbs and the forelimbs are unwebbed. L. laevis is dark olive green with darker blotches outlined in orange. The males have a dark blue throat.[4]

Lepidobatrachus laevis photographed at Kyoto Aquarium

The wide-mouth frog is well adapted to its environment, notably the harsh winter. During this time it will remain inactive underground in a cocoon of shed dead skin which protects it from losing water until they emerge. This species is generally very aggressive and will puff up when threatened to appear larger. If this behavior does not deter the intruder they will make a shrill screech, bite, and corner the target.[5] They are nocturnal and hunt at night, submerged up to their nostrils waiting for prey to pass by. They then lunge and swallow the prey whole. They feed on other frogs, insects, and snails. They have a reputation for being cannibalistic.

L. laevis can produce up to 1400 eggs in a single mating. A pair will reproduce and deposit a mass of fertilized eggs in temporary pools of water. The embryo develops at a rapid rate over two weeks, in order to metamorphize into mobile adolescent form before the breeding pool dries up.[5] The tadpoles are carnivores and cannibalistic at the time of hatching and have nearly adult jaws. They sexually mature in about a year.[6]

It is commonly observed in Paraguay and Bolivia, and less frequently in Argentina. Its natural habitats are the dry and wet Chaco. Breeding may take place in shallow temporary pools and artificial ponds. It is in some areas threatened by habitat loss but there is a large total population size. The species is listed as Least Concern in view of its relatively wide distribution, presumed large population, and because it is unlikely to be declining rapidly enough to qualify for listing in a more threatened category.[1]

These frogs are often kept by keepers with mild experience with frogs or advanced owners. A ten to twenty gallon tank is generally recommended, without aquarium gravel because it causes digestive issues. River stones are a better alternative. Rocks should be sloped to allow the frog to exit the water. They do not require special heating in houses with a comfortable temperature of about 72 °F (22 °C). This species of frog needs to be kept alone or with members of the same species and of equal size, as they will consume anything smaller than themselves.[3]

Wikimedia Commons has media related to Lepidobatrachus laevis.

• Care information for keeping Lepidobatrachus laevis in the home aquarium at the Aquarium Wiki