Diadumene sp.

There are three introduced species of Diadumene in San Francisco Bay, as well as one species (now in the genus Haliplanella) that was once considered to be in the genus Diadumene. Anemones have historically been introduced to San Francisco Bay mixed in with oyster shipments, by ship fouling, and in the ballast water of ships traveling from foreign ports. The identification of anemones is quite challenging to the scientists that work with them. The anemone pictured below resembles Diadumene?cincta, on which extensive (although unpublished) studies have been done which resulted in ideas about it possibly being the same species as the British anemone, Diadumene cincta. The species in question was first reported from San Francisco Bay in the early 1970's, though it may have been present here long before. It commonly occurs as dock fouling, on wharf pilings, on shells partially buried in the sediment, and sometimes intertidally. Like many anemones, this species can reproduce asexually to form clones of itself. Aggregations of clones of Diadumene are often made of up to 200 individuals (from Cohen and Carlton 1995).