First report of Gelidiella ligulata (Gelidiales, Rhodophyta) in Japan

SUMMARY A gelidialean red alga that was newly found in Japanese waters is referred to as Gelidiella ligulata Dawson. It is characterized by erect lanceolate blades developing from a creeping axis that are relatively large in the genus Gelidiella. Among the 22 species currently recognized in the genus, Gelidiella indica Sreenivasa Rao is most similar to G. ligulata and a further comparative study is needed to elucidate the status of G. indica. Gelidiella ligulata and the type species of the genus, Gelidiella acerosa (Forsskal) Feldmann et Hamel, have the unicellular independent attachments that are common to the members of Gelidiella investigated to date. This type of attachment is unique in the Gehdiales and this feature may be a useful taxonomic criterion in distinguishing Gelidiella from other genera.