Seaweed systematics

This work highlights (1) the rich seaweed biodiversity of the Philippines; (2) the need for re-evaluation of several previously reported seaweed taxa within the country; and, (3) the importance of natural history collections (i.e., herbaria) in safeguarding biodiversity information.

Proposal to relegate *Porphyra marcosii* as a later heterotypic synonym of *Phycocalidia vietnamensis* based on morphology, growth and development in culture, and ecology.

A closer look into the taxonomy, distribution, and life history in culture of the poorly-known genus *Iyengaria*, with special reference to the generitype species *I. stellata*.

*Calidia*, a newly proposed genus segregated from *Pyropia*, is renamed to *Phycocalidia*.

Transfer of *iota*-carrageenan-producing seaweeds from *Eucheuma* to *Mimica* gen. nov. The name alludes to the tendency of the type species *Mimica arnoldii* (=*Eucheuma arnoldii*) to imitate corals such as *Acropora*.

Two species of *Rosenvingea* (*R. nhatrangensis* and *R. australis*) are added to the seaweed flora of the Philippines.

*Hydroclathrus stephanosorus* is synonymized to *Talarodictyon tilesii* and a new combined name *Hydroclathrus tilesii* is proposed.

The taxonomy and classification of two new species of *Scytosiphon* (*S. canaliculatus* and *S. tenellus*) was revised based on life history …

*Tronoella ryukyuana* gen. et. sp. nov. and *Hydroclathrus minutus* sp. nov. are described based on samples from southern Japan.

*Hydroclathrus rapanuii* sp. nov. is newly described from Easter Island and the morpho-anatomy of *Chnoospora minima* is also redefined. Based on integrative approaches, new scytosiphonacean genera (i.e., *Dactylosiphon* gen. nov. and *Pseudochnoospora* gen. nov.) were also newly established.