Peahat Larvae are enemies from Ocarina of Time and Majora's Mask. They are the offspring of a Peahat.
Ocarina of Time
When Link encounters a Peahat in Hyrule Field during the evening, the enemy will be sleeping and only spit out the larvae. During the day, the Peahat will spit out larvae if it is chasing Link. Peahat Larvae will continue to follow Link until they're defeated. They will die if they hit Link's shield.
Pea Hat Larva...You don't know
There is only one Peahat that can be found in a hole in Termina Field. Like in Ocarina of Time, it will spit out larvae during the night and they will die against his shield.