Species:

Tupinambis teguixin

Common Tegu

Some other names for this species:

Gold Tegu, Golden Tegu, Black Tegu, Black and Yellow Tegu, Blue Tegu, Colombian Tegu, Colombian Black Tegu, Colombian Black and White Tegu

Anavilhanas Archipelago, Amazonas, Brazil
These large lizards are common throughout most of the northern portion of South America, where they have amassed a large number of somewhat contradictory common names. We saw two of them, but they both raced off before I had any hope of getting a photograph.
Madre Selva Biological Station, Loreto, Peru
Another country, more big tegus that were seen only as they raced out of sight.

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, Peru
Another trip to Peru, another glance at a big tegu that did not want to be captured on film or otherwise. Matt Cage had seen this one near the camp kitchen earlier, and told me where to go look for it. I did, and saw it skulking in the bushes for a moment, before it quickly headed deep into the forest.

Here is a complete list of the herps I saw in the wild on my 2014 MT Amazon Expeditions trip.