Download Key common green algae and Euglenoids

Key to some common green algae and Euglenoids
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7(6').
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8(2').
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9(8).
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10(8').
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11(10').
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12(11').
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13(12').
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14(1').
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15(14).
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16(15).
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17(15').
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21(14').
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23'.
Plants unicellular or colonial
Plants filamentous
Motile by flagella
Nonmotile
Unicellular
Colonial
Cells long and tapering when swimming, round when resting;
one flagellum and a red eyespot
Cells oval; 2 flagella; chloroplast cup shaped
Colony a flat plate, 4-8-16 cells
Colony spherical
Cells close together, usually 16
Cells remote from each other
32 (usually) to 128 cells
Hundreds of cells
Unicellular
Colonial
Cells in two symmetrical halves connected by a narrow isthmus
Cells spherical to oval, sometimes in irregular masses;
on wood or moist soil
Colonies with four cells (sometimes eight) in a row; spines often on
end cells
Colonies with more than four cells
Colonies mucilaginous; cells in groups of four within mucilage
Colonies not mucilaginous
Cells forming a net often visible to the unaided eye
Cells forming a flat plate
Plate irregular; some cells with long, sheathed bristles
Plate regular; marginal cells with lobes. horns, or short spines
Filaments unbranched
Filaments branched
All cells short
Some cells long
Cells with thick walls; chloroplast diffuse
Cells with thin walls; chloroplast in a ring around interior of cell
Chloroplasts star-shaped, usually two per cell
Chloroplasts not star shaped
Chloroplasts spiral
Chloroplasts not spiral
Cell wall thin; chloroplast a flat plate which is broad in surface
view and appears as a thin line in sideview
Cell wall thick
Chloroplast more or less uniform; some cells with apical caps;
swollen oogonia
Chloroplast dense and granular; cells large, with a very few
short rhizoidal branches
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Branches short, with a bulb-like base tapering into a long spine
Branches relatively long
Cells with thick walls
Cells with thin walls
Plant body showing marked differentiation between a single row of large cells forming the main axis
and numerous tufts of short lateral branches with small cells
Plant body not so differentiated
Some terms used in key
Apical caps – Distinctive rings in the tip (apical region) of certain cells. These caps
often are broader than the rest of the cell.
Colonial – Cells present in groups (rather than as single cells which are considered
unicellular).
Diffuse (chloroplast) – Thin, spread out, not dense. Usually appears light in colour.
Filamentous – Cells are threadlike.
Motile – Able to move, often by flagella.
Mucilaginous – Covered in a slimy (mucus-like) layer.
Rhizoidal (branches) – Branched structures that look like roots.
2
14
3
8
4
5
Euglena
Chlamydomonas
Gonium
6
Pandorina
7
Eudorina
Volvox
9
10
Desmids
Protococcus
Scenedesmus
11
Tetraspora
12
Hydrodictyon
13
Coleochaete
Pediastrum
15
21
16
17
Micospora
Ulothrix
Zygnema
18
Spirogyra
19
Mougeotia
20
Oedogonium
Rhizoclonium
Bulbochaete
22
Cladophora
23
Draparnaldia
Stigeoclonium