Eastern Newt (Adult) - Notophthalmus viridescens
I saw several of these salamanders swimming in a small pond in a deciduous forest.
This is the adult form of this salamander. Dorsally, they are olive green with small red spots that are outlined in black, while their bellies are yellow with small black speckles. The juveniles (red efts) are easily recognized for their bright orange-red color. Adults are aquatic, but they can survive on land if their aquatic habitat becomes unsuitable or if there's a drought.
In this video, you can see it trying to decide whether or not to eat a dead beetle. Ultimately, it decided not to:
The eastern newt or red-spotted newt is a common salamander of eastern North America. Eastern newts dwell in wet forests with small lakes or ponds. They can coexist in an aquatic environment with small, non-carnivorous fish, however, their skin secretes a poisonous substance when the newt is threatened or injured. They have a lifespan of 12 to 15 years in the wild, and may grow to 5 inches in length.