Sometimes I wish I really did have a sorting scat - one that could tell me if a rock is fossilized poop or not. It is relatively easy when they are the type that stick to your tongue. With others, especially those without inclusions, it is sometimes hard to determine whether they truly had anal origins.
This coprolite was found in a coastal river by a diver. Sediments from different ages can be washed into rivers. So, it's hard to determine the exact age of fossils found in them. Since megalodon teeth were also found and they lived around 4 to 26 million years ago, this fossilized feces was probably deposited during that same period.
Crocodiles also lived in the area during that time. The shape of this coprolite and lack of inclusions indicate that reptile may have been the sculptor.
Besides having a nice pinch mark, this fossilized poop also has interesting tooth scrapes and impressions on its surface. These are called dentalites.