Structure and reproduction of the genus Ceramium (Ceramiales, Rhodophyta) from Oregon, USA

Genomic and phylogenetic analysis of Ceramium cimbricum (Ceramiales, Rhodophyta) from the Atlantic and Pacific Oceans supports the naming of a new invasive Pacific entity Ceramium sungminbooi sp. nov.

“…Preliminary anatomical study indicated that the Ceramium sp. from California shared close structural similarities with C. cimbricum from Korea, Oregon, and Europe (Rueness 1992, Maggs and Hommersand 1993, Cho et al 2002, Kim 2012. Despite the anatomical and molecular studies of C. cimbricum, its taxonomic status in the north Pacific remains debatable.…”

“…Ceramium is characterized by erect and terete filamentous thalli with complete or incomplete cortication, rounded cortical cells, and irregularly shaped periaxial cells (Kylin 1956). Species are traditionally distinguished based on cortication, apex structure, gland cells, presence or absence of adventitious branches, number of periaxial cells, and tetrasporangial location, depth, and cleavage type (Nakamura 1965, Cho et al 2002.…”

“…In the North Pacific, C. cimbricum was first reported from Japan by Tokida (1948), Korea by Kang (1966), Alaska by Wynne (1987), and listed by Maggs and Hommersand (1993) as occurring in the North Pacific, but with a question mark. Ceramium cimbricum was also reported from several bays in Oregon, USA, on the basis of morphological criteria (Cho et al 2002).…”

First report of the red alga Gayliella fimbriata in the Mediterranean Sea

“…In Gayliella, there is one tetrasporangium originating per periaxial cell, and the tetrasporangium is covered by cortical filaments, whereas in Ceramium, tetrasporangia develop from inner cortical cells as well as from each periaxial cell. In most incompletely corticated Ceramium species, two to three tetrasporangia develop only from periaxial cells (Cho et al 2001a(Cho et al , 2003. Another difference is in regard to rhizoids.…”

“…Another difference is in regard to rhizoids. Unicellular and elongate rhizoids are produced only from periaxial cells with each rhizoid terminating in a digitate tip in Gayliella (Cho et al 2002, as Ceramium recticorticum), whereas both periaxial and cortical cells form multicellular rhizoids terminating in digitate or discoid pads in Ceramium (Nakamura 1965, Womersley 1978, Cho et al 2001a.…”