A checklist on benthic marine algae of the Yum Balam Reserve, Quint;ma Roo,
Mexico, is presented. All species are "new records" for the area because t
his is the first study for the locality 122 taxa were identified, 55 are sp
ecies of Rhodophyta, 44 Chlorophyta and nine Phaeophyta. Barophora oerstedi
i v. occidentalis, Halodictyon mirabile, Hypoglossum involvens and Polysiph
onia ramentacea are new records for the Yucatan Peninsula.