Six new genera and six new species of soft coral, and some proposed familial and subfamilial changes within the Alcyonacea (Coelenterata: Octocorallia)

Five new genera of tropical, shallow water soft corals are described and assigned to the family Xeniidae, and a sixth new genus is placed in the Clavulariidae. Five of the genera have sclerites with previously undocumented microstructure. It is proposed that the four genera with sclerites constructed from anhedral rods and nodules, with various amounts of fusion and "cementing", be placed in the Xeniidae, along with another genus where the sclerites are formed from aggregates of subspherical microscleres. A sixth genus with sclerites in the form of platelets showing only subhedral crystals is placed in the Clavulariidae. Based on the rod and nodule sclerite structure, it is proposed that the family Asterospiculariidae be abandoned, and the genus Asterospicularia be transferred to the Xeniidae, whose definition should be emended to include some genera with all eight mesenterial filaments equally developed. Two new subfamilies, Xeniinae and Ixioninae are proposed: the former for those genera with only the asulcul pair of mesenterial filaments well developed, and the latter for those with all eight filaments developed equally.