Dracaena guianensis Northern Caiman Lizard
Some other names for this species:
Guyana Caiman LIzard
Madre Selva Biological Station, Loreto, PeruJanuary 14, 2013
Northern Caiman Lizard (Dracaena guianensis) Northern Caiman Lizard (Dracaena guianensis) Northern Caiman Lizard (Dracaena guianensis) Northern Caiman Lizard (Dracaena guianensis)
Caiman lizards are highly aquatic, and usually seen basking on logs or branches in a river or along a river's edge. We had hoped to see one on our boat trip from Iquitos to Madre Selva, and I was disappointed that we did not (well, probably did not — we caught a glimpse of some largish lizard on a floating log that might have been a caiman lizard, but that doesn't count).

Imagine our surprise when, on our first full day at the Madre Selva field station, Matt Cage and I glanced up while walking back up the hill from the dining area and saw this monster lizard lumbering across the grounds. Matt made a leap for it, but the lizard put on a burst of speed and disappeared into a small patch of jungle vegetation. Matt called for reinforcements, and in a few minutes five or six of us had the beast more or less surrounded. A few minutes after that it tried to bolt for freedom but was nabbed by one of the crew. We kept it around for a few hours and took many pictures before releasing it into the river.

Caiman lizards feed primarily on thick-shelled aquatic snails, and have massive, powerful jaws for crushing said snails. So it's a darn good thing that this one didn't bite anyone.

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

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