Ceramium botryocarpum is a small red marine alga in the Division Rhodophyta.

[1] Ceramium botryocarpum is a small filamentous branched alga growing as tufts to a height of 12 cm.

The axes are covered by small cells which form a complete cortex over the filaments.

The axes appears banded due to the thinner covering of cortical cells at the internodes.

[3] Epiphytic on other small algae where there are larger brown are not present.