The anurans (Anura, from the Greek ἀν- an- 'without' and οὐρά ourá 'tail') are an order of amphibians commonly known as frogs and toads. Adults are characterized by lacking a tail, having a short and very widened body, and highly developed hind legs adapted for jumping. Anurans are the largest group of amphibians; It is estimated that there are about 6,608 species, divided into 54 families. Most spend their lives in or near water. Its size can vary from a mere 8.5 mm, as is the case of species of the genus Eleutherodactylus, to sizes that exceed 30 cm, highlighting the goliath frog, the largest anuran in the world.