Erythrolamprus typhlus Velvety Swamp Snake
Subspecies I've seen:
E. t. typhlus
Velvety Swamp Snake
Erythrolamprus typhlus typhlus Velvety Swamp Snake
Madre Selva Biological Station, Loreto, PeruJanuary 15, 2013
Velvety Swamp Snake (Erythrolamprus typhlus typhlus) Velvety Swamp Snake (Erythrolamprus typhlus typhlus)
I came across this snake on a solo forest hike on my first morning in the Peruvian rainforest. It was stretched out across part of the trail, and I recognized a snaky shape, though the color did not stand out given the number of other shades of green festooning the forest floor. When I first saw it, it had a standard basically-cylindrical snake shape, but when I detained it for photos it flattened out, exposing the lighter colors between its scales. It took a few minutes to calm down and let me take a few photos, and then it decided enough was enough and started heading back into the vegetation. I intended to capture it to bring back for others to photograph, but it made a quick move into the leaf litter and managed to disappear on me. Fortunately, two other green individuals were caught later by others.

Here is a complete list of the herps I saw in the wild on my 2013 MT Amazon Expeditions trip.

Madre Selva Biological Station, Loreto, PeruJanuary 16, 2013
Velvety Swamp Snake (Erythrolamprus typhlus typhlus)
These snakes are found in a variety of colors including green, red, and slaty gray. This one was coiled up in a palm frond at night, trying but failing to look inconspicuous.
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