RACES OF PERKINSUS-MARINUS

The existence of parasite races is an integral component of host-paras ite interactions with significant implications for host-parasite coevo lution, ecology, and management. Despite nearly 50 years of research, few studies have considered the existence or implications of races of Perkinsus marinus. Nonetheless, several field and laboratory observati ons indicate races exist that vary in virulence or environmental toler ance. One of the keys to understanding and managing P. marinus lies in the identification and characterization of races. A related and equal ly important key is elucidation of its genetic population structure. T his paper discusses our current knowledge concerning P. marinus races and population structures.