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- Got Talent: Peyssonnelia globally showcases its skillsPublication . Gabriel, Daniela; Krayesky, David; Norris, James N.; Schmidt, William E.; Schils, Tom; Fredericq, SuzanneABSTRACT: The crust forming genus Peyssonnelia Decaisne is a taxon of great ecological importance, with some species involved in the establishment of rhodoliths. Comparative morphological and molecular analyses demonstrate a greater diversity of peyssonnelioid species than was previously reported. In chloroplast-encoded rbcL-based trees, species referred to as Peyssonnelia in the literature do not group together, but are scattered among other genera that were not currently placed in the Peyssonneliaceae. Two recently reported genera for the Gulf of Mexico, “ Polystrata” and Metapeyssonnelia, were excluded from the family, and together with a third clade are nested inside the Rhizophyllidaceae of the Dumontiaceae-complex. The Rhizophyllidaceae is newly reported for the Gulf of Mexico, with six species. The number of distinct species of Peyssonneliaceae now present in the Gulf of Mexico has increased from 6 to 21. On the other hand, the number of Peyssonnelia reported for the Azores was reduced from five to one species. Some species placed in Cruoriella and Cruoriopsis actually belong in the Peyssonneliaceae. New combinations are being proposed to accommodate known and new species in Cruoriella, and in two formerly monotypic genera, Sonderophycus and Riquetophycus. The Peyssonneliaceae forms a monophyletic assemblage that could not be maintained in the Gigartinales and thus a new order was constituted, Peyssonneliales, unrelated to the cluster of families centred around the Halymeniaceae of the Halymeniales, or the Gigartinaceae of the Gigartinales.
- Genetic diversity of Gibsmithia hawaiiensis complex (Dumontiaceae, Rhodophyta)Publication . Gabriel, Daniela; Draisma, Stefano; Schmidt, William E.; Schils, Tom; Sauvage, Thomas; Maridakis, Clio; Gurgel, Carlos Frederico Deluqui; Lim, Phaik Eem; Harris, D. J.; Fredericq, SuzanneABSTRACT: The genus Gibsmithia was erected to accommodate a species with the peculiar combination of gelatinous lobes rising from cartilaginous stalks. Based on G. hawaiiensis from Hawaii, it remained monotypic for over 20 years, when three additional species were described from Australia. G. hawaiensis is unique for its furry appearance due to cortical filaments beyond the surface. Gibsmithia have been reported from the Indian Ocean and central and western Pacific, with G. hawaiensis having the widest distribution. Genetic studies based on COI, rbcL and UPA, reveal that G. hawaiiensis is monophyletic with nine distinct species sharing a similar habit. G. hawaiiensis complex exhibits high genetic diversity in Indomalaysia region, with different species presenting genetically variable populations. Species restricted to isolated region as Hawaii or the Red Sea comprises genetically conserved populations. Four of those cryptic species can be distinguished based on characters previously regarded as morphological plasticity: the generitype and the new species G. eilatensis, G. indomalayensis and G. lata distributa. Because specimens of the other species are only available dried onto herbarium paper or in silica-gel, their reproductive characters can not be characterized. New reports of the complex are given to Madagascar, Europa Island, the Red Sea and Guam, and also to new regions of Malaysia, Indonesia, the Philippines and the French Polynesia.
- Phuket: Rhodogorgonales Capital of the WorldPublication . Draisma, Stefano; Muangmai, Narongrit; de Lima Gabriel, Daniela; Schils, Tom; Saunders, Gary; Kim, Hocheol; Yoon, Hwan SuABSTRACT: The Rhodogorgonales is an order within the rhodophyte subclass Corallinophycidae whose members exhibit calcification in the form of calcite. The order was erected in 1995 to include two monotypic genera described from the Caribbean. The thallus texture of Rhodogorgon ramosissima is cartilaginous, whereas Renouxia antillana is gelatinous. In the following two decades, Indo-Pacific specimens of cartilaginous and gelatinous rhodogorgonaleans, were assigned to these two species, respectively. In 2016, a third genus and species, Rhodenigma contortum, was described from microscopic filaments collected in Western Australia and included in the order based on DNA sequences. In 2018, Rhodogorgon flagellifera, was described from Western Australia based on the shape of cortical cells, but without DNA sequences. In 2019, Renouxia marerubra, was described from the Red Sea based on morphology and DNA sequences. In Thailand, Rh. ramosissima and Re. antillana have been reported from the east and west coast, respectively. However, without DNA sequences, their identification should be questioned. The present study explored the Rhodogorgonales diversity around Phuket island on the Thai west coast using multiple DNA markers. Two Renouxia species and three Rhodogorgon species were found. One of the Thai Renouxia species was conspecific with Re. marerubra. The other was conspecific with or very closely related to Rhodenigma contortum, suggesting that Rhodenigma should be synonymized with Renouxia. A Rhodogorgon with cylindrical branches could be linked to Rh. flagellifera based on comparison of a DNA sequence of its type specimen. The other two, a flabelliform and a truncated form, represent undescribed Rhodogorgon species. With five species, Phuket can currently lay claim to the unofficial title of “Rhodogorgonales Capital of the World”, a title it will likely have to pass on to an island in the Coral Triangle in the future when this region is more fully explored.