Showing papers on "Mantella published in 2012"

Phylogeography of the poison frog Mantella viridis (Amphibia: Mantellidae) reveals chromatic and genetic differentiation across ecotones in northern Madagascar

Abstract: Mantella viridis is a threatened poison frog species endemic to the ecologically very heterogeneous northern region of Madagascar. The existence of several colour morphs within M. viridis and its very low genetic differentiation to the allopatrically distributed Mantella ebenaui raise questions about the processes driving the differentiation between these poison frog populations and about their taxonomic status. Using a DNA fragment of 476 nucleotides of the mitochondrial cytochrome b gene from 240 individuals of this species complex, we investigated the genetic variability of all known colour morphs of M. viridis, sampling this species throughout its known range, as well as several populations of M. ebenaui. Our genetic results confirm that M. viridis and M. ebenaui are closely related but reveal that no haplotype sharing occurs between these two taxa. Further, our molecular analyses provided evidence for barriers to gene flow among some of the colour morphs. Estimates of overlap of bioclimatic envelopes as assessed by ecological niche modelling also suggest a distinct bioclimatic niche of some of the lineages studied.

An endogenous bile acid and dietary sucrose from skin secretions of alkaloid-sequestering poison frogs.

Abstract: The skins of Madagascar poison frogs (Mantella) and certain Neotropical poison frogs (Epipedobates, Dendrobates) secrete the new bile acid tauromantellic acid (1), which was found in both wild-caught and captive-born frogs. This is the first molecule of endogenous origin detected in skin secretions from these taxa. Sucrose was also detected in secretions from wild-caught Mantella but not in captive-born frogs, suggesting a dietary origin.