Plocamium cartilagineum is a medium-sized red marine alga.
Description
Plocamium cartilagineum is an erectred alga growing to 10 cm in length. The main axes is flattened with regular flattened branches on both sides. The branches are long and short alternately, the short ones on one side are opposite the longer on the other side. These longer branches bear two or three short curved branches in series, comb-like. The plants are fully corticated. This branching pattern is similar to Plocamium lyngyanum and Plocamium maggsiae the other European species which have only recently been distinguished.