Guibemantis cf. albolineatus undescribed species
The 2nd edition of Glaw and Vences placed these frogs in Mantidactylus albolineatus. Due to genetic differences, the 3rd edition places these frogs in a closely related undescribed species instead, referred to as Guibemantis sp. aff. albolineatus "Andasibe". (Note that the genus Mantidactylus was split into several genera between those two publications.)
Analamazaotra Special Reserve (Perinét), Toamasina province, MadagascarApril 23, 2007
undescribed species (Guibemantis cf. albolineatus)
Guibemantis "albolineatus" is a not-yet-described species that's one of a group of closely related frog species that all live almost entirely among the spiky fronds of plants in the genus Pandanus. Often you can find two or three or four species living in the same plant. A number of these Pandanus plants are scattered around the entrance grounds of Analamazaotra Reserve, and as dusk arrived I started moving from plant to plant trying to photograph these little frogs before they got spooked and hopped back into the plants' water-filled axils.

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

Analamazaotra Special Reserve (Perinét), Toamasina province, MadagascarApril 23, 2007
undescribed species (Guibemantis cf. albolineatus) undescribed species (Guibemantis cf. albolineatus)
The different Pandanus-dwelling species are hard to tell apart. I had originally identified this as G. flavobrunneus, but Madagascar frog expert Devin Edmonds helpfully corrected me.
Analamazaotra Special Reserve (Perinét), Toamasina province, MadagascarApril 24, 2007
undescribed species (Guibemantis cf. albolineatus)
The next night, I got a few more photos of Pandanus-dwelling frogs around the entrance to Analamazaotra while we were waiting for darkness to fall. I also thought this one was G. flavobrunneus, but once again Madagascar frog expert Devin Edmonds helpfully corrected me.
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