Reproduction of Sphaerococcus coronopifolius (Gigartinales, Rhodophyta) in natural populations of the Lazio coasts (central Italy) and in culture

As Sphaerococcus coronopifolius Stackhouse (Gigartinales, Rhodophyta) is a seaweed that has considerable potential for commercial uses, and as its life history in the various seas where it lives has not yet been thoroughly explored, we carried out a pilot study on the reproduction in nature and in vitro culture of field specimens established on the coasts of the Lazio region (Tyrrhenian Sea, central Italy). Spermatangia were not observed on the gametophyte (S. coronopifolius) and the tetrasporophyte of the species (Haematocelis fissurata) was not found either in the study site or in culture. As the carpospores developed directly into the gametophyte, we may conclude that this species reproduces itself, in both the study site and in culture, through a direct-type life history. It may thus be possible to use the variety of the clonal individuals growing on the coasts of Lazio for a future cultivation of S. coronopifolius on a large scale.