Copeoglossum nigropunctatum South American Spotted Skink
Some other names for this species:
Black-spotted Skink, Amazonian Skink
These skinks were formerly placed in the genus Mabuya. Work is being done on this genus, and it's likely that C. nigropunctatum will be split into multiple species eventually.
Mamirauá Sustainable Development Reserve, Amazonas, BrazilNovember 15, 2006
South American Spotted Skink (Copeoglossum nigropunctatum)
Fallen trees in the rainforest cause light gaps that are popular with the lizard crowd, as this skink is cheerfully demonstrating.

I believe the skinks in this area are currently all considered C. nigropunctatum. If you are an Amazonian skink expert, please send me mail to confirm or deny this identification.

Here is an account of the four days we spent at Uakari Floating Lodge in the Mamirauá Sustainable Development Reserve.

Madre Selva Biological Station, Loreto, PeruJanuary 15, 2013
South American Spotted Skink (Copeoglossum nigropunctatum) South American Spotted Skink (Copeoglossum nigropunctatum)
This is the only type of skink (at least as currently defined) found in this area of Peru, so there's no trouble identifying it. Whenever the sun is out, nearly every sunny patch in the forest has at least one of these skinks scuttling in the leaf litter or basking on a log.

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 18, 2013
South American Spotted Skink (Copeoglossum nigropunctatum)
Though these skinks are common, they are also quite skittish; you have to sneak up on a lot of them in order to get a few decent photos.
Santa Cruz Forest Reserve, Loreto, PeruJanuary 21, 2013
South American Spotted Skink (Copeoglossum nigropunctatum)
This wary-looking youngster allowed me to approach more closely than your average C. nigropunctatum.
Madre Selva Biological Station, Loreto, PeruJanuary 16, 2014
South American Spotted Skink (Copeoglossum nigropunctatum)
I'm not sure if this is a male/female pair, or just an arbitrary couple of skinks choosing the same basking spot.

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

Madre Selva Biological Station, Loreto, PeruFebruary 3, 2016
South American Spotted Skink (Copeoglossum nigropunctatum)
This robust adult was less wary than most of these skinks that I've seen.
Santa Cruz Forest Reserve, Loreto, PeruFebruary 8, 2016
South American Spotted Skink (Copeoglossum nigropunctatum)
The messy trailside vegetation provides many fine basking spots for the local skink population.
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