Where seen? This green seaweed with small fleshy ‘umbrellas’ is commonly seen on some of our (Singapore, re: “warm”) shores, growing on coral rubble near reefs.
Features: The seaweed has structures that look like fleshy umbrellas; with a thick circular portion (about 1-1.5cm across) on a little stalk. These little umbrellas emerge along the length of a ‘stem’ that creeps over the surface. Bright yellow-green to bluish-green.
Human uses: It is eaten in some places and used as medicine for its antifungal properties and ability to lower blood pressure.
(From http://www.wildsingapore.com/wildfacts/plants/seaweed/chlorophyta/peltata.htm, May 26th, 2010)