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- 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.
- The Renouxia files: the richness is out there!Publication . Gabriel, Daniela; Norris, James N.; Schmidt, William E.; Harris, D. J.; Fredericq, SuzanneABSTRACT: In 1989, a gelatinous red alga was reported for the Caribbean, to which no species name, genus, order or even family could be assigned. Renouxia antillana was finally described in 1995 and accomodated in a new order and family (Rhodogorgonales, Rhodogorgonaceae) along with Rhodogorgon ramosissima described six years earlier based on material from reefs in Belize. For more than 20 years, the genus has remained monotypic, with rare reports in the Caribbean and in the Indo-Pacific (from Malaysia to French Polynesia). Recent collections in Egypt resulted in the first record of Renouxia in the Red Sea. DNA sequence analyses indicate that the specimens belong to a new species. The cox1 pairwise distance among the Red Sea specimens is 0.0-0.2%, while the distance between these and the generitype is 7.5 -7.7%. This interspecific nucleotide diversity is as high as the diversity between R. antillana and Rhodenigma contortum (7.2-7.5%), the third species in the family. RbcL pairwise distances are also high (6.7% within Renouxia, and 9.1-9.6% between Renouxia and Rhodenigma), indicating the possibility that the new species belongs to a new genus. Morphological and anatomical studies are underway to formally describe the new taxon.