An analysis of the nematocysts of the beadlet anemone Actinia eguina and the green sea anemone Actinia prasina

Numerous studies of their population genetics have reported incipient repro ductive isolation among sympatric populations of the common intertidal bead let anemone Actinia equina. This has lead to certain morphs being raised to specific status. A study of the nematocysts of the green sea anemone Actin ia prasina and three genetically isolated morphs of A. equina was undertake n to establish that mean nematocyst length could act as diagnostic phenotyp ic characters within a morphologically variable group. The results support genetic and ecological evidence for the specific status of the three red/br own coloured morphs of A. equina. The data are discussed with respect to th e ecology of Actinia and concepts of species, but more work is required bef ore the specific status of A. prasina can be confirmed.