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ABSTRACT. Sim ilarity of call site in anu ran community in Northwestcrn São Paulo State, Brazil (Amphibia, Anura). The breadth and overlap Df mal e call site were determined for 15 anuran species fi·om a temporruy pond in N0I1hwestem São Paulo State, Brazil. Four measurements were made at lhe point of capture Df each calling male and the frequency of mating call was detennined. There was a high overlap along each variable Df call site, but less than 28% 01' possible species pairs presented high overlap for ali variables. Taxonomically related species pairs calling from grass presented spatial and acoustic segregation, while those calling from the ground presented only acoustic segregation. The similarity of call site seems to be not only related to the taxonomic relationships but also with the body size and spatial heterogeneity.

ABSTRACT. The diet of tadpoles of 13 anuran species was determined to verify whether food resource partitioning occurs and whether the degree of diet similarity is related to taxonomic affinity. Tadpoles of all species studied were mainly herbivorous, except for these of Leptodactylus fuscus (Schneider, 1799) which were mycophagous. Although some species had exclusive items in their diet, most tadpole species ingested the same items, but differed in the amount of each item consumed. Two guilds were found: tadpoles that feed on diatoms on the pond bottom, and tadpoles that feed on Oedogonium Link, 1820 algae in midwater. Diet similarity was related to the taxonomic relationship, microhabitat and feeding behavior of tadpoles indicating that the community organization is complex and resulting from the interaction of several parameters. KEY WORDS. Community ecology, food partitioning, microalgae.RESUMO. Dieta dos girinos de um açude temporário no sudeste do Brasil (Amphibia, Anura). Determinou-se a dieta dos girinos de 13 espécies de anuros, com o objetivo de verificar se ocorre partilha de recursos alimentares e se o grau de similaridade na dieta é relacionado ao parentesco, inferido pela proximidade taxonômica. Os girinos de todas as espécies estudadas foram preponderantemente herbívoros, exceto os de Leptodactylus fuscus (Schneider, 1799) que foram micófagos. Embora algumas espécies tenham apresentado itens exclusivos em sua dieta, os girinos da maioria das espécies ingeriram os mesmos itens, diferindo na quantidade consumida de cada item. Duas guildas foram encontradas: girinos que se alimentam de diatomáceas no fundo do corpo d'água e girinos que se alimentam de algas do gênero Oedogonium Link, 1820 à meia-água. A similaridade na dieta foi relacionada à proximidade taxonômica, ao microhabitat e ao comportamento de alimentação, indicando que a organização desta comunidade é complexa e resultante da interação entre vários fatores. PALAVRAS CHAVE. Ecologia de comunidade, partilha de alimento, microalgas, sudeste do Brasil.

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Vocal communication traits of Hyla nana and Hyla sanborni, of the nana species group, were studied from August 1997 until June 1999 in two large permanent ponds located in an open field in Botucatu, São Paulo State. One hundred thirty-one individuals, 71 of H. nana and 58 of H. sanborni, were recorded in the beginning of their vocalization activity and during chorus vocalization. The rhythms of sound emission on the two occasions were different. An advertisement call consists in a consecutive series of simple notes in rapid succession. Both species have two types of notes in their advertisement calls, here named types A and B. Type A notes are introductory and have a longer and higher pulse number and are emitted more frequently in the beginning of vocalization activity. Introductory notes are the first to be emitted in chorus activity. Type B notes are secondary, of shorter duration and lower pulse number, and are emitted during chorus vocalization. The notes of both types differ significantly in their temporal structure. Both species present acoustic segregation in both spectral and temporal structure.