From the Super Mario Wiki
Priscilla is an insect creature found on Yoshi's Island. She is the boss of World 3 in Yoshi's Island DS.
If the Yoshi jumps into or over the sand which she inhabits at the wrong time, Priscilla may eat him, causing him to lose all of his eggs. Yoshi can jump from platform to platform in Priscilla's path to lure her out of her sand pit and throw an egg at her. Alternatively, a Glide Guy may come out and lure her; this second method, however, happens periodically and can therefore take quite some time. She also spits Needlenoses.
Names in other languages
||Derived from the French expression "avoir un petit creux", meaning "feeling a bit peckish"
- Priscilla's behavior is likely based on the larva of an antlion, a type of real world insect (these larvae are also known as doodlebugs). Antlion larvae are well-known for digging pits in sand and devouring any insects that fall into them.