Solisphaera gen. nov. (Prymnesiophyceae), a new coccolithophore genus from the lower photic zone

Abstract

J. Bollmann, M.Y. Corté S, A. Kleijne, J.B. Østergaard and J.R. Young. 2006. Solisphaera gen. nov. (Prymnesiophyceae), a new coccolithophore genus from the lower photic zone.Phycologia 45: 465–477. DOI: 10.2216/05-14.1

Solisphaera gen. nov. (Prymnesiophyceae) is described from the lower photic zone of the Pacific Ocean, the North Atlantic Ocean and the Gulf of Mexico. Differences in coccolith morphology between Solisphaera and members of Rhabdosphaer-aceae are certainly substantial enough to warrant the erection of a separate genus that should probably be categorised asincertae sedis aff. Rhabdosphaeraceae. The new genus accommodates three new species, S. emidasia sp. nov., S. blagnacensis sp. nov. and S. helianthiformis sp. nov. and the presence of a corona of process-bearing coccoliths around the cell is a key feature that unites the three species in the new genus Solisphaera, while the shape of these coronal coccoliths provides the main character for separating them at species level. A remarkable feature of this genus is the tight interlocking of the coronal coccoliths, in almost all collapsed coccospheres the circle of coronal coccoliths remains intact. This is evidently due to the presence of notches at the base of the process into which the rims of adjacent coccoliths lock. All three species are restricted to the lower photic zone in the areas studied and apparent preferences for different depth levels of S. emidasia and S. blagnacensis, as well as their nutrient and light requirements, have to be confirmed by further analysis.

Key Words::

• Solisphaera gen. et sp. nov
• Atlantic Ocean
• coccolithophores
• Gulf of Mexico
• lower photic zone
• Pacific Ocean
• morphology
• taxonomy

ACKNOWLEDGMENTS

We thank the captains and the crews of R.V.MALCOLM BALDRIGE, R.V.METEOR and R.V.POSEIDON for their efforts in facilitating the collection of data in the Pacific Ocean and in the Atlantic Ocean. We are very grateful to Dr Vita Pariente and many of her colleagues at Texas A&M University for providing samples from the Gulf of Mexico and for much correspondence. Francisco P. Chavez and Kurt R. Buck, from Monterey Bay Aquarium Research Institute, California, organised JBØ's participation in the JGOFS cruise in the Pacific Ocean. Andrea Spiedt sampled coccolithophores during R.V.POSEIDON cruise 212. Philippe Gasser (EMPA) and Martin Müller (IAP ETH Zürich) assisted in the examination of the samples from the type locality in the Atlantic Ocean. Silvia Clavadetscher provided the Latin translation and Peter Zeeberg is thanked for suggestions for the Latin names.

This study was supported by a PhD-grant, funded by the Faculty of Science, University of Copenhagen, and a travel grant from the Fiedler Foundation to JBØ. This work is a contribution to the EC-MAST project CANIGO (Subproject 3, ‘Particle Flux and Oceanography in the Eastern Boundary Current system’), EC contract No. MAS-CT9-0060 and the EC-TMR program CODENET, EC contract N^o ERB-FRMX-CT97-0113. The Swiss Federal Office for Education financially supported JB (BBW No. 95.0355).