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Thalassiosira nordenskioeldii Cleve 1873
Cells often united in chains. Diameter = 10-50 µm. Resting spore: + Distinctive features: Shape of cell and long external tubes of processes. Distribution: Cold water species of the northern hemisphere

	Chaetoceros socialis Lauder 1864 Chains in colony Diameter = 3-15 µm Resting spore: + Common spring bloom species worldwide.
	*Skeletonema costatum* (Greville) Cleve 1873 Cells united in long chains Diameter = 2 - 21 µm, pervalvaraxis 2-61 µm Resting spore: + Note: Distinctive features: Small cells linked firmly with long external tubes of the marginal strutted processes. Worldwide. In reality many species?
	*Chaetoceros debilis* Cleve 1894 Cells united in chains. Diameter = 10-40 µm. Resting spore: + Distinctive features: Chains spirally twisted, basal part of setae distinct, setae extending outward from the spiral, resting spore. Worldwide mainly in cold waters
	*Chaetoceros socialis* Lauder 1864, again - This species grows in large "nests" and densities during a bloom can reach several million cells/l. This organization of the cells probably helps them keep afloat (sinks slower). C. socialis = several species?+
	*Chaetoceros decipiens* Cleve 1873 Cells united in chains. Diameter = 9-84 µm. Resting spore: + Distinctive features: With several chloroplasts, sibling setae partly fused, terminal setae thicker than the others. Worldwide
	*Fragilariopsis oceanica* Cleve Hasle The length of the cell ranges from 20-60um, width 12-40 um. The frustule in valve view is broadly elliptical. Widespread, mainly cold waters.
	*Odontella aurita* (Lyngbye) C. A. Agardh 1832 Cells united in chains and often on substrate Diameter = 10-95 µm Resting spore: ? Widespread.
	Most (all?) diatoms can form spores. They are silicified cells that are close to or totally? metabolic inactive. To teh left are spores of Chaetoceros debilis. When we start cultures we germinate spores collected fro the seabed simply by adding nutrients and light. Especially interesting for us is the first phase of growth for these algae in that they apparently can set up a tremendous growth speed during the first divisions.
	*Thalassiosira anguste-lineata* (A. Schmidt) G. Fryxell et Hasle 1977 Cells united in chains. Diameter 14-78 µm Resting spore: + Distinctive features: Arrangement of central processes. Worldwide
	*Thalassiosira gravida* Cleve Medium-sized (13-62 µm diameter), with dense, radially arranged areolae. Strudded processes are evenly spread out on the valve surface, except for a central cluster. A labiate processes is fairly obvious in the margin.
	Thalassiosira nordenskioeldii Cleve 1873 Cells often united in chains. Diameter = 10-50 µm. Resting spore: + Distinctive features: Shape of cell and long external tubes of processes. Distribution: Cold water species of the northern hemisphere
	*Phaeocystis pouchetii* Hariot Lagerheim Solitary flagellate and colony. Haptophycean. Motile cell c. 5 µm long, colony up to 1.5-2 mm. Resting spore: ?? Probably.Also Phaeocystis globosa and Phaeocystis antarctica. The P. pouchetii we have in the north may possible be several species. Worlds most common algae?