DIFFERENT CHEMICAL TYPES OF PLOCAMIUM VIOLACEUM (RHODOPHYTA) FROM THE MONTEREY BAY REGION,CALIFORNIA1

Differences in the halogenated natural products of Plocamium violaceum Farlow can be noted from different sites in the Monterey Bay region, California. Specimens from the northern region produce a set of alicyclic halogenated monoterpenes which are not synthesized by those from the southern region. Instead, the latter elaborates a set of acyclic halogenated monoterpenes not observed from the former. This situation is invariant regardless of life history forms or different seasons. Similarly, the composition of halogenated monoterpene structures from P. cartilagineum (L.) Dixon varies at different locations. From the data presented herein we conclude that at least two chemical types can be identified for P. violaceum based upon differences in their halogenated products. Thus we suggest that the north Monterey form can be designated as chemotype α and the southern one as chemotype β.