2022/06/24 by Richard V. Dumilag, Giuseppe C. Zuccarello
Earth and Planetary Sciences · Environmental Science · #Coral and Marine Ecosystems Studies #Marine Biology and Ecology Research #Marine and coastal plant biology
paper · doi:10.1080/00318884.2022.2079283
crossref issued 2022/06/24 · crossref published 2022/06/24 · crossref published-online 2022/06/24 · openalex publication_date 2022/06/24 · crossref created 2022/06/24 · crossref published-print 2022/09/03 · openalex created_date 2025/10/10 · crossref deposited 2026/06/17 · crossref indexed 2026/08/01 · openalex updated_date 2026/08/01
The term ‘eucheumatoids’ designates a group of genera in the family Solieriaceae that are the source of some of the most valuable algal products in cultivation. While economically important in the tropics, much of its taxonomy is yet to be fully resolved. The eucheumatoid species Mimica arnoldii is a Batesian mimic of corals that was recently transferred to its own genus from Eucheuma based primarily on peculiarities of habit and a lack of medullary rhizoids, in contrast to the generitype Eucheuma denticulatum that has the latter. We studied the diversity of Mimica arnoldii from samples collected in the Philippines to determine their genetic variation, relationships to other eucheumatoids, and whether its two distinct morphological expressions, which have been named as varieties, are genetically different. We produced a phylogeny using a three-gene concatenated dataset, and used the variable mitochondrial cox2-3 spacer to determine intraspecific variation and the degree of correlation between sequence-variation and varietal status. Our results showed that Mimica is a distinct genus, and that intra-specific molecular data did not correspond to the morphology-based varieties, although it did correlate with geographical distribution. Our results also indicate that Kappaphycus, as presently circumscribed, contains species with (Kappahycus alvarezii, K. striatus and K. malesianus) and without (Kapppahycus cottonii) internal medullary hyphal core, and that K. cottonii is sister to the remaining Kappaphycus species. We thus propose Kappaphycopsis gen. nov. for K. cottonii for the species of Kappaphycus without internal medullary rhizoids (anaxiferous).