The diet of Scinax angrensis (Lutz) tadpoles in an area of the Atlantic Forest (Mangaratiba, Rio de Janeiro) (Amphibia, Anura, Hylidae)

Abstract

Scinax angrensis (Lutz, 1973) is an endemic species, which occurs in low altitude hillside forests, distributed from the municipalities of Mangaratiba to Parati in the south of the state of Rio de Janeiro, Brazil. The aim of this study was to compare the morphology of S. angrensis tadpoles in two different stages of development, and verify their feeding spectrum. The mouth morphology of the two stages studied (27 and 37) appeared similar, with a difference in the size of the oral opening as well as an increase in the dimensions of the body. The examined species presented a trophic spectrum comprised of algae, protozoan, rotifers, microcrustaceans, nematodes, vegetation and invertebrate remains, fungus hyphae, and sand grains. Significant differences were found between dimensions of the two stages, but not between diets, although a differentiated preference with regards to planktonic items has been verified. The results suggest that the partitioning of feeding resources is not only related to morphology and occupation of different microhabitats but also to the feeding behaviour of tadpoles. The relevance of important food items to the natural diet of S. angrensis tadpoles, especially the diatoms and filamentous algae, reveal the importance of the periphytic community to the conservation of this species in the Atlantic Forest.

Diet and food resource partition among benthic tadpoles of three anuran species in Atlantic Forest tropical streams

“…The presence of fungi in the diet of tadpoles is also rarely reported in literature even though it is an important component in oligotrophic habitats (Altig et al 2007). Studies that address the importance of fungi in the diet of tadpoles were not found, however, Rossa-Feres et al Pfennig et al 2006;Sousa Filho et al 2007;Wickramasinghe et al 2007), and were usually associated with the diet of tadpoles in the later stages of development, unlike the three species of this study, which were in the early stages of development. The high nutritional value of invertebrates in terms of protein and energy is worthy of note (Bowen et al 1995).…”

“…A high diversity and abundance of algae is usual in tadpoles of different anuran species (Dutra & Callisto 2005;Sousa Filho et al 2007). However, the ingestion of a large amount of algae by anuran larvae will not necessarily result in nutritional gain (Pryor 2003;Akers et al 2008).…”

“…With some exceptions (e.g., Kupferberg 1997;Dutra & Callisto 2005;Sousa Filho et al 2007), there are relatively few studies of the diet of anuran larvae in lotic environments. Studies of the composition of the diet of tadpoles are especially important in the tropics, where despite taxonomic diversity being severely threatened by factors that can cause irreparable declines; little is known of the trophic importance of tadpoles in many aquatic environments (Altig et al 2007).…”

T Ropical Tadpole Assemblages: Which Factors Affect Their Structure and Distribution?

“…Heyer 1973). On the other hand, feeding behavior of tadpoles may be partially coupled with morphology and microhabitat distribution resulting in differences in diet composition, which contribute with food partitioning (Inger 1986, Rossa-Feres et al 2004, Escheverría et al 2007, Souza Filho et al 2007.…”

Ecología alimentaria de spea multiplicata (Anura: Scaphiopodidae) durante su desarrollo larvario

“…Conocer de qué se alimentan los renacuajos permite comprender las interacciones bióticas y abióticas que ocurren en el ecotono entre las zonas terrestres y acuáticas; así como entender la estructura trófica a escala local lo que revela los enlaces entre comunidades. Estos estudios también permiten entender el grado de susceptibilidad de las diferentes especies de anuros debido a los cambios ambientales (De Sousa et al, 2007). Desde luego permiten determinar si existe o no selección de elementos alimenticios exclusivos que satisfagan las necesidades nutricionales de los renacuajos para poder llevar a cabo la metamorfosis.…”