Three new species of Alveolophora (Aulacoseiraceae, Bacillariophyceae) from Miocene deposits in western North America

Abstract

Usoltseva M., Kociolek J.P. and Khursevich G. 2013. Three new species of Alveolophora (Aulacoseiraceae, Bacillariophyceae) from Miocene deposits in western North America. Phycologia 52: 109–117. DOI: 10.2216/12-022.1

The genus Alveolophora was previously reported only from fossil localities in Asia and the Russian Far East. Three new species of this extinct diatom genus were described from Miocene sediments in western North America, A. bradburyi, A. nevadica and A. americana. The taxa were described using light and scanning electron microscopic observations of valve morphology. These new species from North America were compared with species previously described from Asia. Polymorphism in longitudinal or transverse ribs was detailed. The ribs sometimes formed anastomosing networks, a feature unknown in all previously described members of the genus. Comparison of frustular morphology with other members of the genus as well as the Family Aulacoseiraceae was made. Fossil taxa can provide unique insights into character evolution and phylogenetic relationships.

Key Words::

• Alveolophora
• Aulacoseiraceae
• Miocene
• Miosira
• North America
• Rimoportulae
• Ultrastructure
• Velum

ACKNOWLEDGEMENTS

We thank two anonymous reviewers for comments and improving this paper, and we thank Carrie Graeff for her assistance with SEM. This work was supported by an integration project of Siberian and Far-Eastern Branches of the Russian Academy of Sciences (No. 5) and President Grant (MK-2617.2011.5.).

SUPPLEMENTARY DATA

Supplementary data associated with this article can be found online at http://dx.doi.org/10.2216/12-022.1.s1.