AGLAOTHAMNION FLEXIBILE SP-NOV AND SEIROSPORA-VIRIDIS SP-NOV (CERAMIACEAE, RHODOPHYTA) FROM PUERTO-RICO

Two new species of Callithamnieae (Ceramiaceae, Rhodophyta) are descri bed from the Caribbean. Aglaothamnion flexibile sp, nov. is a delicate sublittoral plant growing almost exclusively on coarser algae. Branch ing is irregularly radial below to subdichotomous above, with ultimate laterals forming corymbs. The main axes are straight below but marked ly flexuous to zig-zag above. Plants are ecorticate but may produce lo ose non-corticating rhizoidal filaments. Seirospora viridis sp. nov. i s a heavily corticated sublittoral plant characterized by its bright g reen iridescence. It grows epiphytically on coarser algae or attached to coral and other hard substrata. Branching is radial throughout with a 1/4 rotation; ultimate branchlets are flabellate and slightly incur ved. Seirospora viridis does not produce seirosporangia. Both species have uninucleate vegetative cells. Generic assignments are based on po st-fertilization development, carposporophyte structure and overall mo rphology.