Proceedings of the Second Mediterranean Symposium on Marine

PROCEEDINGS OF THE SECOND MEDITERRANEAN SYMPOSIUM ON MARINE VEGETATION (ATHENS, 12-13 DECEMBER 2003)
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Mature tetrasporangia are spherical; tetrahedrically divided and measure 35-40 µm in
diameter. In culture, tetrasporangia are soon released as a unit and numerous spores
germinate. Germination follows <strong>the</strong> Gelidium-type pattern.
Thalli <strong>of</strong> <strong>the</strong> Apulian Batophora sp. colonise stones (Fig. 4a) at 0-3 m depth. Plants are
bright green, s<strong>of</strong>t and delicate. The thallus consists <strong>of</strong> a cylindrical stalk, sometimes
branched (Fig. 4b), attached to <strong>the</strong> substrate by rhizoids, and numerous whorls <strong>of</strong>
laterals. Reproductive organs were never observed on ei<strong>the</strong>r field or lab-cultured thalli.
Fig. 4.Batophora sp. Detail <strong>of</strong> (a) an unbranched thallus; (b) a branched thallus.
Careful morphological and morphometric observations highlighted that <strong>the</strong> thalli <strong>of</strong>
Dasycladus were smaller than those <strong>of</strong> Batophora and never branched; <strong>the</strong>ir main axis
was 4-6 times wider and <strong>the</strong> first order laterals were shorter and more numerous (Fig.
5a, b).
In regard to diagnosis at species level, according to Berger and Kaever (1992) in <strong>the</strong>
genus Batophora <strong>the</strong> species are distinct on <strong>the</strong> basis <strong>of</strong> a few vegetative characters but
above all on <strong>the</strong> basis <strong>of</strong> <strong>the</strong> reproductive ones. Comparison between Mexican and
Apulian specimens pointed out some slight differences, probably due to <strong>the</strong> different
geographical and climatic conditions (Table 6).
Fig. 5.Batophora sp. Scheme <strong>of</strong> a whorl in (a) Dasycladus and (b) Batophora.