The life history and phenology of Callithamnion corymbosum (Rhodophyta: Ceramiaceae) in Newfoundland

Abstract

C. corymbosum (Sm.) Lyngb. reaches its known northern limits in the western Atlantic on the south and southwest coast of insular Newfoundland [Canada] where it occurs only as tetraspore-bearing plants which reproduce by vegetative fragmentation. It is abundant in the immediate subtidal in late summer and fall but is not an obvious component of the algal flora in the winter and spring when it occurs principally as detrital fragments. Tetrasporangia occur in the fall and their production in culture is temperature-dependent. Discharged tetraspores have only limited viability in culture and their behavior in nature is unknown.