Porpita porpita 

Blue Button

Florida native

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These pelagic marine organisms occasionally wash up on Florida beaches, sometimes in great numbers. Blue buttons passively float on the surface of tropical and sub-tropical waters of the Atlantic, Pacific and Indian oceans.
Each blue button is actually a colony of hydroids that live in the round chambered float made of a chitin-like material. The disks range from 2-4cm (~3/4 - 1-1/2in.) in diameter and when alive are mostly brown on top. The individual zooids range from a bright blue turquoise to yellow, and each have specialized functions such as prey capture, digestion or reproduction. In the center of the underside is the 'mouth' which takes in food and expels waste. The tentacles have stinging cells to stun prey. These are not powerful enough to harm humans, but some people have reported an irritation from contact.

Porpita porpita is a member of the Porpitidae - Chondrophore family.

iNaturalist profile for this species

Date record last modified: Feb 08, 2026