Grateloupia lithophila Børgesen 1938

    Thalli firm, gelatinous, brownish olivaceous to violet in colour and grows up to 15 cm high. Thallus attached by a small basal disc; erect fronds caesiptose, 0.3-1.2 cm broad, simple or rarely divided and tapering from the middle to both ends, the apices obtuse. Thallus 190-280 µm thick; medullary filaments 4-8 µm broad, stellate cells 12-17 µm in diameter and with arms 40-65 µm long. Inner cortical cells loosely arranged, irregular, 8-14 µm long and 3-9 µm broad; outer cortex compact consists of smaller, rounded cells, 5-8 µm long and 3-4 µm broad

    Cystocarps embedded, scattered all over the thallus, subspherical, 100-160 µm in diameter with prominent ostiole; carpospores rounded polyhedral, 8-17 µm diameter