- publication
- 01-10-2002
Allogromiid foraminiferans are distributed over a wide range of marine habitats, but some are also reported from freshwater environments. Most of these descriptions date back to the 19th century. Among them, five species of freshwater foraminiferans have been described and redescribed from Lake Geneva by the Swiss protozoologist Eugène Penard. The different foraminiferal species were classified by Penard in the genus Gromia, which at that time included both, filosean and granuloreticulosan species and were later grouped by De Saedeleer in two allogromiid genera, Allelogromia and Diplogromia. We collected several sediment samples from Lake Geneva and from two other bodies of freshwater in Switzerland and investigated them subsequently under a stereomicroscope. None of the forms described by Penard were observed. On the other hand, we have obtained foraminiferal DNA sequences from DNA extracts of the same sediment samples. Phylogenetic analysis of these sequences shows that they branch with a clade of saccamminid foraminiferans, represented by the genera Ovammina and Cribrothalammina. This is in agreement with the observed morphological similarity between Penard’s species and the marine saccamminids used in our study. The possibility that our sequences belong to some undetermined naked foraminiferans, however, cannot be excluded and the molecular identification of the species described by Penard must await the confirmation by sequencing DNA of isolated specimens.
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