During the last thirty years, intra and interspecific variation in gut morphometrics has been extensively investigated (Starck, 1999). However, most of this research was conducted in birds, mammals and reptiles (see Piersma and Lindstrom, 1997; and Starck, 1999 for reviews); and to date, practically nothing is known about this topic in postmetamorphic amphibians (see Larsen 1992). The aim of this note is to report and compare intestinal length of four South American anuran species: Leptodactylus ocellatus (Leptodactylidae), Hyla p. pulchella (Hylidae), Bufo gr. granulosus (Bufonidae), and Pseudis minutus (Pseudidae).