Colpomenia is a genus of brown macroalgae (or seaweed) in the family Scytosiphonaceae.

First, was the transfer of all previous members of Colpomenia with erect, finger-like thalli into the new genus Dactylosiphon based on morphoanatomical, molecular, and life history observations[4].

Second, was the formal separation of Colpomenia tuberculata (now Encephalophycus tuberculatus) from the rest of the genus due to the stark differences in its morphology molecular phylogeny.

[9] There are three observed life history strategies for this genus: (1) heteromorphic diplohaplontic, the gametophyte (N) and sporophyte (2N) are both free-living and equally distinct bodies, however, the gametophyte (N) has a diminutive form and releases anisogamous (i.e., unequal in form and size) gametes to form the zygote (2N) which will later on develop into the sporophyte (2N) that will release unispores that will develop into the gametophytes (N); (2) heteromorphic, monophasic, wherein the female gamete (N) alone gives rise to the sporophyte (2N), and the female unispore develops into the gametophyte; and lastly, (3) monomorphic monophasic, the sporophyte independently regenerates through the production of plurispores while the gametophytes also independently grow via the production and settlement of its zooids.

Natural product chemistry research on this genus has revealed that it harbors important bioactive compounds (i.e., sulfated polysaccharides) that have the potential to limit tumor growth.