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56 | Filaments

Pacific Seaweeds

Cladophora Green tuft

Class Siphonocladophyceae Order Cladophorales Family Cladophoraceae

Number of Species

Cladophora (Greek=branch bearer) is a complex tangle of species that requires investigation; currently there are eight species listed in our area. It is an example of a complex assemblage of filamentous seaweeds including Rhizoclonium.

Description

Plants are typically densely branched but lack the hooks of Acrosiphonia (p. 55) and therefore form loose clumps or extensive mats, which may reach 30 cm (12 in) in length but are usually less than 5 cm (2 in) long. The cells are microscopic and multinucleate. Plants are usually attached to rock.

A freshwater species, Aegagropila linnaei (formerly known as Cladophora aegagropila) forms filamentous balls that may reach 30 cm (12 in) in diameter. The balls gracefully and repeatedly move from lake bottom to lake surface. At sunrise the balls are lifted off the lake bottom by oxygen bubbles produced by photosynthesis and trapped by the filamentous ball. When the ball reaches the surface, some of the oxygen is released to the atmosphere and the ball

Tufts of Cladophora sp. at low tide.

Cladophora columbiana and detail of filament arrangement (right).