From the Super Mario Wiki
The title of this article is official, but it comes from a non-English source. If an official name from an English source is found, the article should be moved to its appropriate title.
Neijī is a rare enemy that can be found in the Mario Zone of Super Mario Land 2: 6 Golden Coins. It is a living screw that appears only near the end of the first level of this zone. They wind themselves out of the ground and bounce toward Mario to attack, attempting to drill into him from above. They can be defeated by jumping on them or using a Fireball.
Names in other languages
|From 「ねじ」, which can translate to screw.