What are small black round rodents without a tail?

There is no known rodent that is small, black, round, and without a tail.

Rodents, by definition, are mammals with incisor teeth that continuously grow, and they all have tails.

It is possible you are thinking of a different type of animal, or perhaps you are describing a specific type of rodent with some inaccuracies. Could you please provide more details about the animal you're thinking of?

For example:

* Where did you see this animal? (e.g., in your home, outside, in a specific region)

* What was its size approximately? (e.g., smaller than a mouse, bigger than a rat)

* Did it have any other distinguishing features? (e.g., color patterns, fur texture)

This information will help me understand what animal you are describing and provide you with a more accurate answer.