Diet of larval Ambystoma rivulare (Caudata: Ambystomatidae), a threatened salamander from the Volcán Nevado de Toluca, Mexico

Abstract

Diet of larval Ambystoma rivulare (Caudata: Ambystomatidae), a threatened salamander from the Volcán Nevado de Toluca, Mexico. Several species of salamander in the genus Ambystoma occur in the mountains surrounding Mexico City and are considered at risk of extinction. However, little is known about their ecology and natural history. The Toluca Stream Siredon (Ambystoma rivulare September 2014, we examined the diet of larval A. rivulare from a stream on the Volcán Nevado de Toluca in Mexico to provide insight into the suitability of the habitat to support this population of salamanders. Ostracods accounted for approximately 90% of all prey items consumed by larval A. rivulare. The number of ostracods found in stomachs increased with individual body size, but the proportion of ostracods in stomachs did not vary with body size. Nematodes were observed in approximately one third of the stomachs we examined. The diversity of prey in the diet of A. rivulare in the stream we studied is low and dominated by a single prey taxon, ostracods. Our results suggest that if environmental conditions in the stream change such that ostracods are negatively affected then the longterm persistence of this population of A. rivulare might be in jeopardy.

Natural history of the critically endangered salamander Ambystoma leorae (Caudata: Ambystomatidae) from the Río Tonatzin, Mexico

“…On a broader level our results are consistent with observations of A. leorae and other Mexican Ambystoma in that they occupy narrow, slowmoving streams with oxygenated water with muddy or sandy bottoms (e.g., A. leorae, VegaLópez and Alvarez-S. 1992, Sunny et al 2014a, Monroy-Vilchis et al 2015A. rivulare, Brandon and Altig 1973, Bille 2009, Lemos-Espinal et al 2015A. rosaceum, Anderson 1961, Anderson andWebb 1978).…”