From the Super Mario Wiki
Spindels are a sub-species of Thwomp that first appear in Super Mario 64. They are cylindrical creatures made of stone that attack by rolling over their targets. The name "Spindel" comes from the word spindle, which is the part of a spinning wheel that holds the yarn that is being spun. Spindels also resemble a giant cylinder with a thread of yarn spun around it, but with a face. They may be a precusor to the Rhomps that appear in Super Mario Galaxy 2, as the Rhomps are alive and the Spindels are mummified, like Grindels.
Spindels appear exclusively in the pyramid of Shifting Sand Land, where they can be found rolling back and forth in some sections of the pyramid. There is a safe spot where Mario can hide to avoid being squished.
The Spindels have a partial resemblance to Grindels, as both appear mummified, and share their cylindrical shape with Rhomps, which appear in Super Mario Galaxy 2.
The Spindel in the pyramid in Super Mario-Kun
A Spindel appears in volume 16 of the Super Mario-Kun manga. It tries squashing Mario and the Bob-omb Buddy accompanying him, but fails and crashes.
Names in other languages
|Portmanteau of don (colliding sound) and guruguru (turning around something, now for round shape).
||From Walze (barrel) and the name Walter