Halimeda spp.
Chlorophyta, Halimedaceae
Authority: Lamouroux
Hawaiian name: none
Characteristic feature: Round connected green plates.
Description: Plants with erect, decumbent, or prostrate axes and branches conspicuously jointed, consisting of a series of calcified internodes (segments) connected by narrow, short, uncalcified, flexible nodes; segments compressed, flattened (basal segments sometimes cylindrical), discoid, cuneate, reniform; internally segments formed from numerous parallel non-septate filaments that branch to form outer layers; outermost ends of branchlets often adherent after decalcification, aligned to form surface layer; thallus attached by thick stalk, or by multiple groups of rhizoids from segments in contact with substrate.
Habitat: Intertidal reef flats, shallow subtidal, to deep water, on rock, coral, or in sand
Hawaiian distribution: All main Hawaiian Islands, including the Northwestern Hawaiian Islands.
Other: May incorporate sand and coral into the fibrous holdfast.