Feeding ecology in the small neotropical amphisbaenid Amphisbaena munoai (Amphisbaenidae) in southern Brazil

Abstract

ABSTRACT. We analyzed the alimentary tract of 66 specimens of Amphisbaena munoai Klappenbach, 1969 from the Serra do Sudeste, state of Rio Grande do Sul, southern Brazil. Forty specimens (60.6%) had prey items in their gut. The diet consisted mainly of small invertebrate prey, such as termites, insect larvae and ants. The most abundant prey item was termites, found in 62.5% of the non empty stomachs. The high number of individual prey items in the majority of stomachs, the small size of the regular prey items, and the absence of gut content in specimens of A. munoai kept alive for about two days, indicate that this species forages very frequently. The predominance of fossorial prey items and the occasional records of nomadic ants lead us to suggest that A. munoai usually feeds underground, and occasionally forages on the surface.KEYWORDS. Amphisbaena munoai, diet, feeding behavior, natural history, southern Brazil. RESUMO. Ecologia alimentar da pequena anfisbaena neotropical Amphisbaena munoai (Amphisbaenidae) no sul do Brasil.Analisamos o trato digestório de 66 exemplares de Amphisbaena munoai Klappenbach, 1969 procedentes da Serra do Sudeste do Rio Grande do Sul, Brasil. Quarenta espécimes (60,6%) possuíam presas. A dieta é composta basicamente de pequenos invertebrados, como térmitas, larvas de insetos e formigas. As presas mais abundantes foram térmitas, encontradas em 62,5% dos estômagos não vazios. O elevado número de presas em cada indivíduo na maioria dos estômagos, o tamanho pequeno de presas regulares e a ausência de itens alimentares em espécimes de A. munoai mantidas vivas por aproximadamente dois dias, indicam que está espécie é forrageadora freqüente. A predominância de itens alimentares fossórios e o encontro ocasional de formigas nômades nos permitem sugerir que A. munoai usualmente se alimenta abaixo da terra e ocasionalmente na superfície.

Subterranean ants (Hymenoptera, Formicidae) as prey of fossorial reptiles (Reptilia, Squamata: Amphisbaenidae) in Central Brazil

“…Interestingly we recorded workers of the epigaeic Eciton and Labidus praedator (Ecitoninae) in the stomach contents of amphisbaenian reptiles, which indicate that amphisbaenians forage also on the soil surface, as suggested by Bernardo- Silva et al (2006) and observed by Gorzula et al (1975). Also, one of the ant individuals found in the stomach contents of an Amphisbaena alba is a large soldier of Eciton mexicanum, suggesting also that these reptiles are not reluctant to invest against potentially aggressive ants.…”

“…Several behavioral associations have been reported between ants and different reptiles, such as predation (Riley et al, 1986;Cruz-Neto & Abe, 1993;Barros Filho & Valverde, 1996;Colli & Zamboni, 1999;Kearney, 2003;Wetterer & Moore, 2005;Staller et al, 2005;Bernardo-Silva et al, 2006;Whitfield & Donnelly, 2006;Goldsbrough et al, 2006), and inquilinism (Brandão & Vanzolini, 1985;Riley et al, 1986;Oliveira & Della Lucia, 1993).…”

“…However, the prey choice mechanism remains uncertain for most species in this group (López et al, 1991). According to some studies (Riley et al, 1986;Cruz-Neto & Abe, 1993;Barros Filho & Valverde, 1996;Colli & Zamboni, 1999;Kearney, 2003;Bernardo-Silva et al, 2006), the diet of these reptiles consists mainly of small arthropods, mostly isopterans, hymenopterans (especially ants), coleopterans and arachnids. Ants have relatively great importance (volumetric and numeric) in the amphisbaenian diet (Colli & Zamboni, 1999); there are records of both colonial and nomadic species in the stomach contents of these reptiles (Riley et al, 1986;Bernardo-Silva et al, 2006).…”

Reproduction and feeding ecology of Amphisbaena munoai and Anops kingi (Amphisbaenia, Amphisbaenidae) in the Escudo Sul-Rio-Grandense, southern Brazil

“…Information about the natural history of A. munoai was presented by BERNARDO-SILVA et al (2006), who studied the diet of the species in an area close to where the present study was developed (Escudo Sul-RioGrandense). Nothing was known until now about the reproduction of this species.…”

“…This is one of the highest amphisbaenian diversity in the world (80% of South American species and 35% of world species) (GANS, 2005) but the natural history of this group has been little explored (e.g. BARROS FILHO & VALVERDE, 1996;COLLI & ZAMBONI, 1999;ANDRADE et al, 2006;BERNARDO-SILVA et al, 2006). On the other hand, regions of temperate climate, mainly in North America, Europe and Australia, although less diverse, revealed Squamata reptile species that were good models for studies emphasizing natural history, related to the easy observation/capture and to the relative frequency (SEIGEL & COLLINS, 1993).…”