Designed by Paul Smith 2006. This website is copyrighted by law.
Material contained herewith may not be used without the prior written permission of FAUNA Paraguay.
Photographs on this web-site were taken by Paul Smith, Hemme Batjes, Regis Nossent,
Alberto Esquivel, Arne Lesterhuis, José Luis Cartes, Rebecca Zarza and Hugo del Castillo and are used with their permission.
ORDER ANURA - FROGS AND TOADS
Seventy-nine species in nine families occur in Paraguay, the name Anura means "without tail" and is one of the most instantly recognisable characteristics of the adult forms. Anurans have four legs, the hind legs being muscular and well-developed. The skin possesses various types of glands for defence and for moistening the skin. Males sing to attract a mate (generally after dark), the vocalisations produced being species specific but influenced by external factors such as ambiental temperature. Their ability to breathe through the skin allows them to hold their breath whilst calling (the mouth and nose are closed) and vibrate their vocal chords by passing air backwards and forwards across them from the lungs. Inflatabale air sacs in the gular regions act to amplify the sound. Fertilisation is external, the male clasping the female (amplexus) and fertilising the ovules as she lays them. Larvae (commonly known as tadpoles) breathe through gills, adults breathe with lungs and through the skin. Larvae are filter feeders or scrape organic material, adults feed almost exclusively on invertebrates and (in very large species) on small vertebrates.
Skeletally a urostyle is present, formed by a fusion of the post-sacral vertebrae. There are five to nine presacral vertebrae. The astralegus and calcaneum (tarsals) are elongated and at least partly fused.
REFERENCES
Cei JM 1980 - Amphibians of Argentina - Monitore Zoologico Italiano Monografia 2
Fouquette MJ (undated) - Synopsis of Recent Amphibians to Genus - Arizona University
Straneck R, de Olmedo E & Carrizo GR 1993 - Catalogo de Voces de Anfibios Argentinos Tomo 1 - LOLA, Buenos Aires.
Whitfield P Ed.1984 - Longman Illustrated Animal Encyclopedia - Guild Publishing, London.