Abstract

We studied the composition of the benthic marine macroflora in Laganas Bay (National Marine Park of Zakynthos, Ionian Sea, Greece). Seasonal samples were collected by SCUBA-diving from April 2001 to February 2003. A total of 182 taxa at specific and infraspecific rank of macroalgae was found, 146 of which are new records to Zakynthos Island and 12 to the Greek coasts. The vegetation of most of the rocky substrata is characterized by species of the canopy-forming genus Cystoseira, while that of soft bottoms is characterized by large meadows of Posidonia oceanica. Two other phanerogams (Cymodocea nodosa and the lessepsian immigrant Halophila stipulacea) also occur on soft bottoms, the former developing dense meadows, while the latter occurs in only a restricted area. The invasive green alga Caulerpa racemosa var. cylindracea was of frequent occurrence on hard and soft substrata.