Reproductive Phenology of Pterocladiella capillacea (Rhodophyta: Gelidiales) from Southern Baja California, Mexico

Abstract

The abundance of vegetative and reproductive fronds of Pterocladiella capillacea (Gelidiaceae) from an intertidal population at Lobos Point, on the Pacific coast of southern Baja California, Mexico, was measured bimonthly between March 1998 and January 1999. Fronds with tetrasporic sori occurred throughout the year, although in low percentages with respect to the total amount of fronds: monthly means ranged between 0.5% (May) and 6.0% (July). Fronds with cystocarps and fronds with spermatangia were found only in January, with even lower percentages: 0.15% and 0.10%, respectively. The overall predominance of reproductive tetrasporophytic fronds over reproductive gametophytic fronds is common in natural populations of the Gelidiaceae. Reproductive phenology, however, varies widely within this family, even within the same species, as is the case for P. capillacea. Little is known about factors affecting the reproductive phenology of this cosmopolitan alga; field and laboratory studies are needed to provide a reliable predictive framework.