Protoperidinium Bergh (Dinoflagellata) in the southeastern Mexican Pacific Ocean: part I

Thecal morphology was studied, with an emphasis on sulcal plates, in 17 mainly tropical-boreal and tropical Protoperidinium species from the southeastern Mexican Pacific Ocean: P. brochii , P. claudicans , P. conicum , P. crassipes , P. depressum , P. divergens , P. elegans , P. excentricum , P. grande , P. latispinum , P. minutum , P. obtusum , P. oviforme , P. pentagonum , P. punctulatum , P. venustum and P. vulgare . These data were compared with those in published literature on the morphology of sulcal plates. Records of the species in the study region were compiled, and maps of global distribution for 11 are presented. The range of intraspecific variability in the morphology of sulcal plates still remains largely unknown, and accumulated relevant data need to be evaluated properly.