Observations sur (Cystoseiraceae, Phaeophyta): une espèce méditerranéenne rare et peu connue

A study of the morphology of the brown alga Cystoseira susanensis , a species known only from the type locality (Susa, Lybia) and from southeastern Sicily, was carried out on numerous thalli occurring in littoral rockpools at Marzamemi (Syracuse, Italy). The species has a short primary axis bearing numerous secondary axes close to the base. Such a branching pattern probably led Nizamuddin to consider his species as caespitose, while, on the contrary, it is not caespitose. Observations in culture of the first phases of segmentation of zygotes as well as of the first growth stages of germlings are also provided.