Biometric relationships in the red sea pen Pennatula rubra (Cnidaria: Pennatulacea)

Colonies of the red sea pen Pennatula rubra sampled by trawling in the northwestern Mediterranean Sea were analyzed. Biometric parameters such as total length, rachis length, number of polyp leaves, wet weight and dry weight were measured and related to each other by means of regression analysis. The most reliable measures for future inferencing of colonies size and biomass through visual techniques were individuated in order to allow a...