Sentoku, A. & Ezaki, Y. 2012: Regularity and polarity in budding of the colonial scleractinian Dendrophyllia ehrenbergiana: consequences of radio-bilateral symmetry of the scleractinian body plan. Lethaia, Vol. 45, pp. 586–593.
Regularities and polarity in budding of the azooxanthellate scleractinian Dendrophyllia ehrenbergiana were examined with the aim of understanding the developmental constraints on the formation of colonies. Its mode of budding, in light of the orientations of directive septa of offsets and the inclination angle of budding, is consistent with that of other dendrophyllids; however, the offsets of D. ehrenbergiana only occur near the two primary septa on the convex side of individual corallites, showing a plane of bilateral symmetry with a distinct polarity. These regularities and polarity are seen in the axial and its derived corallites throughout growth. Of note, the polarity at individual corallites is clearly reflected in subsequent colony growth by the branching pattern and corallite number. These characteristics imply the presence of radio-bilateral symmetrical constraints on the asexual reproduction of the Scleractinia and give us invaluable clues to the understanding of shape-making mechanisms of marine modular organisms. □Asexual reproduction, azooxanthellate coral, budding, colony, Dendrophyllia ehrenbergiana, polarity.