Fontina Gen. nov. (Bacillariophyta): a new diatom genus from a thermo-mineral spring of the French Massif Central (France)

Abstract

Light and scanning electron microscope observations on the genus Fontina gen. nov. from a thermo-mineral spring of the Massif Central (France) are presented. Based on morphology, the new genus shows features that have not been described previously, such as the stria pattern, interrupted at the valve face/mantle junction and composed of one long, slit-like areola on both valve face and mantle. Externally, areolae are closed by hymenes. Fontina arverna sp. nov. is described as the typus generis of Fontina. This new genus was compared with some similar freshwater genera such as Adlafia, Chamaepinnularia, Genkalia, Germainiella, Microfissurata and Nupela. So far, we are unable to establish an evolutionary link or cladistic association with currently known genera. The new genus is described from a sampling site characterized by high conductivity and high carbonate concentration, brackish conditions and whose water originates deep in the crust (high lithium concentration).

Keywords:

• Fontina arverna
• mineral springs
• new genus
• raphid diatom
• taxonomy

Acknowledgements

We thank Diba Khan-Bureau (Three Rivers Community College, Norwich, Connecticut, USA) for her precious English corrections and Eduardo A. Morales (Laboratório da Água, Universidade de Évora, Évora, Portugal) for his valuable comments. We also thank Eric Papon and Marion Lefeuvre for their time in the field and for making easier access to the spring. Two anonymous reviewers are thanked for their valuable comments.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Funding for this research was partly provided in the framework of the project DIATOMS (LIST - Luxembourg Institute of Science and Technology), and by the SIVU Couze Chambon amont, Communauté de communes du Massif du Sancy, and Fontaines Pétrifiantes of Saint-Nectaire.