Peyssonnelia stratosa sp. nov. (Peyssonneliaceae, Rhodophyta), a new shallow-water species from Puerto Rico, Caribbean Sea

A new Peyssonnelia species from shallow water habitats in southwest Puerto Rico is described. Peyssonnelia stratosa is yellowish beige or reddish in color and is composed of small overlapping blades 2-3 cm in diameter and forms extensive colonies. Peyssonnelia stratosa exhibits small cells at mid level in the perithallus, both immediate distal and proximal cells being much longer, giving the appearance of stratification within the perithallus. Tetrasporangia, cut off laterally from an enlarged proximal nemathecial cell, reach 190 m in length.