Acrosiphonia arcta

Arctic sea moss

Authority: (Dillwyn) Gain

The dark green thallus forms distinctive mats or tufts up to 6 cm (2.25 in) tall. Uniseriate filaments branch from sides of cells, and branches are held together by colorless rhizoids (curved branches are rare). The tips of the branches are usually rounded and at least as broad as lower portions. Cells are longer than broad. Seaweeds in this genus wring out like a sponge when squeezed, drying out the thallus.

Habitat

This species occurs on boulders and bedrock in the mid to low intertidal of protected to semi-exposed habitats in spring and summer.

North Pacific Distribution

Arctic Ocean, Bering Sea, and Aleutian Islands, Alaska to Oregon; Russia

Former scientific names

Conferva arcta, Cladophora arcta, Spongomorpha arcta

Similar taxa

Acrosiphonia spp. Cladophora sericea

References

AlgaeBase (opens in a new tab)

Last updated December 26, 2010