|
M. Elbraechter, L. Medlin, M. Lange, G. Donner and M. Schweikert
More than 100 species have been described among the genera Prorocentrum Ehrenberg, Exuviaella Cienkovsky , Dinopyxis Stein, Postprorocentrum Gourret and Mesoporos Lillick belonging to the order Prorocentrales. At least 5 species are producing ocadaic acid and/or other DSP-toxins. Identification of the genus Mesoporos is easy and will be excluded from our analyses. In the last review of the genus Prorocentrum, Dodge (1975) regarded Exuviaella, Dinopyxis and Postprorocentrum as later taxonomic synonym of Prorocentrum. Dodge recognized only 21 species. In the last few years several new species, in particular benthic, potentially toxic ones, have been described. New features for separating species have been introduced, including molecular biological characters and the genus Exuviaella has been reinstated. Therefore a revision of the Prorocentrales is urgently needed. We correlated morphological and cytological characteres now used for delimitation of the species with molecular genetic analyses. The species investigated, including some so far undescribed ones fall into 2 major clades which do not correspond to morphological and/or ultrastructural distinct groups. Each of these clades can be further subdivided into 3 smaller clades that correspond to species clusters. We do not accept the reinstatement of the genus Exuviaella and regard a splitting of the genus Prorocentrum into different genera as premature given the present state of knowledge.
|
