Wanaan

The Wanaan (ワナーン) is an indestructible trap robot created to catch intruders. It hides out in pipes and if Mega Man stands on a Wanaan pipe for too long, it will leap out with a snap to get him with its jaws. Wanaan is found in Hard Man's stage and Wily Stage 2 in Mega Man 3.

Crunchran
Crunchran (クランチラン) is an enemy from Mega Man 8 and Mega Man & Bass similar to the Wanaan. They have mobile holes and can be destroyed with weapons that fire low to the ground. They are located in Astro Man's stage and a few of Wily's levels.

Other Media
A Wanaan appears on the Variant Cover of Mega Man Issue 40 (Archie Comics).