First record of Palisada mari-rubri (Ceramiales, Rhodophyta) from the Mediterranean Sea along with three proposed transfers to the genus Palisada

The first occurrence of Palisada maris-rubri (K.W. Nam et Saito) K.W. Nam (Ceramiales, Rhodomelaceae) from the Mediterranean Sea, is reported. To date the species was known only from tetrasporic specimens from the type locality (Ras Muhammed, Sinai, Egypt, Red Sea). Mediterranean thalli share nearly all vegetative and reproductive features with Red Sea specimens showing more robust thalli with axes to 3 mm broad and ultimate branchlets to 1000 m broad, absence of intercellular spaces between medullary cells and epidermal cells in transverse section with a palisade arrangement. Male and cystocarpic thalli are recorded for the first time. Moreover, the analysis of characters of three species of Chondrophycus previously known from the Mediterranean Sea (C. patentirameus (Montagne) K.W. Nam, C. tenerrimus (Cremades) G. Furnari et al. and C. thuyoides (Kützing) G. Furnari) led us to conclude that they belong to the genus Palisada. The following new combinations are formally proposed: P. patentiramea (Montagne) Serio et al., P. thuyoides (Kützing) Serio et al., P. tenerrima (Cremades) Serio et al.