Cliona Viridis(Schmidt, 1862) andCliona Nigricans(Schmidt, 1862) (Porifera, Hadromerida): evidence which shows they are the same species

Abstract

Abstract The three typical growth stages of the genus Cliona (alpha, beta and gamma) have been studied in the boring species “complex” Cliona viridis. These different growth habitus have been sometimes described as different species (C. viridis and C. nigricans). In recent studies carried out off the Balearic Islands, we found that the growth stages exhibit different colour tinges, bathymetric distribution, and abundance along a vertical light gradient. These growth habitus cannot be considered as belonging to different species but to ecological adaptations because the relationship between the tylostyle length values (spicule size) and the papilla diameter (growth form) follow the allometric growth curve. The different colour tinges of the specimens were due to variations in the amount of zooxanthellae, stage of development and the depth at which the specimens were found.