{{Taxobox
| color = lightgreen
| name = ''Calamus''
| regnum = Plantae
| divisio = Flowering plantMagnoliophyta
| classis = Liliopsida
| ordo = Arecales
| familia = Arecaceae
| genus = '''''Calamus'''''
| genus_authority = Auct. ex Carolus LinnaeusL.
| subdivision_ranks = Species
| subdivision =
''many, see text''
}}
'''''Calamus''''' is a genus of the palm family Arecaceae. These are among several genera known as rattan palms.
''Calamus australis'' is known as the hairy mary.