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Your search keyword '"Aulacoseira islandica"' showing total 2 results
Start Over Descriptor "Aulacoseira islandica" Journal diatom research
2 results on '"Aulacoseira islandica"'

1. Diatom assemblages from an Eemian palaeolake in Northern Europe with morphological observations of rare Aulacoseira sp. resting spores.

Author

Plikk, Anna, Risberg, Jan, and Helmens, Karin F.

Subjects
*SPORES, *DIATOMS, *NAVICULA, *BOTANY, *MORPHOLOGY, *PLEISTOCENE Epoch
Abstract

An overview of the diatom flora of the last interglacial (Eemian) lacustrine gyttja deposit at Sokli, northeastern Finland is presented together with descriptions including photomicrographs of resting spores similar to the Aulacoseira islandica-skvortzowii group, not found in recent material from Europe. Comparisons are made with literature data on similar taxa. The morphology of the resting spores (e.g., the number of striae and areolae in 10 µm) links them to the A. islandica-skvortzowii group, but the lack of vegetative cells in the Sokli record makes the determination of true synonymy difficult. The presence of spores similar/related to the A. islandica-skvortzowii group in the Sokli Eemian palaeolake may reflect a more widespread distribution of this group in the past. [ABSTRACT FROM AUTHOR]

Published
2021
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2. AN ANALYSIS OF TYPE MATERIAL OFAULACOSEIRA ISLANDICA(O. MÜLLER) SIMONSEN

Author

Yelena V. Likhoshway and Marina Usoltseva

Subjects
Type (biology), medicine.anatomical_structure, medicine, Mineralogy, Aulacoseira islandica, Anatomy, Aquatic Science, Mantle (geology), Areola, Geology
Abstract

The type material of A. islandica from Botanical Museum of Copenhagen collection was studied with the light microscopy. The seasonal variability of some characteristics (height, diameter of the valves and areolar density in 100 μm2) was analyzed. The type diagnosis of the species (diameter up to 25.5 μm, height of the valve mantle up to 28 μm, the number of areola rows between 9 to 16 in 10 urn, the number of areolae in a row, 9 to 20 in 10 μm) was enlarged and supplemented with data on the number and location of rimoportulae. The latter are located close to the ringleist, in the middle of the mantle and on the spherical valves of auxospores. The total number of them on the valves ranges from 1 to 4. The outer opening of the rimoportulae substitute for areolae in the row.

Published
2007
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