The Yellow-Spotted Amazon River Turtle has a slightly domed carapace, broadest in the middle with a trace of a medial keel which may reach 15" in the female (record length is 27"). The carapace is olive to dark gray or brown. The yellow plastron and bridge may develop dark blotches with age. The elongated head has a protruding snout and is gray to olive or brown with prominent yellow spots on each side. There is a barbel on the chin of most, but those found in Amazonia may have two. The jaws are dark brown or black and the chin has a transverse yellow bar with a yellow spot below each corner of the mouth. Juvenile carapace is brown to greenish gray with a narrow yellow border and an obvious medial keel. This turtle belongs to the suborder of turtles called "side necks". This means that instead of pulling the head back into the shell they lay their head sideways into a groove between the carapace and plastron and next to a front foot. Females tend to be much larger (sometimes almost twice as large) in size with a short tail, a light buff or brown head and black eyes. The males retain the yellow spotted head and have greenish eyes.