Molecular taxonomy of Dunaliella (Chlorophyceae), with a special focus on D. salina: ITS2 sequences revisited with an extensive geographical sampling
1 Departamento de Biotecnología. División de Investigación y Desarrollo Tecnológico. Instituto Tecnológico de Canarias (ITC). Pozo Izquierdo, 35119 Sta. Lucía, Canary Islands, Spain
2 Departamento de Biodiversidad Molecular y Banco de ADN, Jardín Botánico Canario "Viera y Clavijo"-Unidad Asociada CSIC, Apartado de correos 14 de Tafira Alta, 35017 Las Palmas de Gran Canaria, Canary Islands, Spain
Aquatic Biosystems 2012, 8:2 doi:10.1186/2046-9063-8-2Published: 30 January 2012
We used an ITS2 primary and secondary structure and Compensatory Base Changes (CBCs) analyses on new French and Spanish Dunallela salina strains to investigate their phylogenetic position and taxonomic status within the genus Dunaliella. Our analyses show a great diversity within D. salina (with only some clades not statistically supported) and reveal considerable genetic diversity and structure within Dunaliella, although the CBC analysis did not bolster the existence of different biological groups within this taxon. The ITS2 sequences of the new Spanish and French D. salina strains were very similar except for two of them: ITC5105 "Janubio" from Spain and ITC5119 from France. Although the Spanish one had a unique ITS2 sequence profile and the phylogenetic tree indicates that this strain can represent a new species, this hypothesis was not confirmed by CBCs, and clarification of its taxonomic status requires further investigation with new data. Overall, the use of CBCs to define species boundaries within Dunaliella was not conclusive in some cases, and the ITS2 region does not contain a geographical signal overall.