Mantidactylus cf. betsileanus undescribed species
The 2nd edition of Glaw and Vences placed these frogs in Mantidactylus betsileanus. Due to genetic differences, the 3rd edition places these frogs in a closely related undescribed species instead, referred to as Mantidactylus sp. aff. betsileanus "Toamasina".
Masoala National Park, Toamasina province, MadagascarMay 1, 2007
undescribed species (Mantidactylus cf. betsileanus) undescribed species (Mantidactylus cf. betsileanus) undescribed species (Mantidactylus cf. betsileanus)
I spent a long time chasing the first of these frogs around in a shallow brook. The other two were much more cooperative. Initially I thought that the smaller frog was a different species from the larger one, perhaps Mantidactylus biporus, which according to Glaw and Vences is often found living together with M. betsileanus. But upon further inspection of the photos, I'm reasonably confident that the smaller one is just a youngster of the same species. Also, M. biporus isn't known from anywhere near the Masoala peninsula.

The 3rd edition of Glaw and Vences say that this species has been found "only in highly degraded areas where it occurs in flooded swamp areas (near Toamasina) or a small source (Maroantsetra) flowing through forest remnants". The ones photographed here are from small streams in an area of mostly undegraded forest in Masoala National Park, so maybe this was something of a minor discovery. The white spots on the snout are diagnostic of Mantidactylus betsileanus and its close relatives, so I'm pretty certain that I've gotten the identification correct.

Here is a list of all the reptiles and frogs I saw on this trip to Madagascar.

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