FIRST RECORD OF THE GENUS TOGULA (GYMNODINIALES, DINOPHYCEAE) AND OF THE SPECIES T. JOLLA FOR THE SOUTH-WEST ATLANTIC COASTAL WATERS

In the framework of a phytoplankton and biotoxin monitoring program implemented since 2008 in marine coastal waters of the Buenos Aires Province (Argentina), a gymnodinioid, photosynthetic dinoflagellate was isolated from a sample collected in Santa Teresita, establishing the strain LPCc007. The strain was identified as belonging to the psammophilic genus Togula by light microscopy based on the following distinctive characters: morphology of the cell dorso-ventrally flattened, and course of the cingulum, highly asymmetric, descending, with its ends displaced by about one to two thirds of the total length of the cell and joined by an oblique intercingular groove. The comparative morphological analysis between the motile vegetative cells of the isolated strain and the three species of the genus described to date, did not reveal significant differences that would allow it to be determined at a specific level. Instead, the pattern of development of longitudinal grooves on the hypocone of cells about to undergo mitosis observed in strain LPCc007, perfectly agrees with that described for T. jolla as a differential character. The morphological identification was consistent with LSU rDNA (D1-D2) based phylogeny that showed the sequence aggregation in the T. jolla clade. This is the first report of the genus Togula and the species T. jolla from Argentina and the South-West Atlantic Ocean coastal waters. En el marco de un programa de monitoreo de fitoplancton y biotoxinas implementado desde 2008 en aguas marinas costeras de la Provincia de Buenos Aires (Argentina), un dinoflagelado gimnodinioide, fotosintético, fue aislado de una muestra colectada en Santa Teresita, estableciéndose la cepa LPCc007. La cepa fue identificada como perteneciente al género Togula con microscopía óptica con base en los siguientes caracteres distintivos: morfología de la célula dorso-ventralmente aplanada, y curso del cingulum, altamente asimétrico, descendente, con sus finales desplazados por cerca de uno a dos tercios de la longitud total de la célula y unidos por un surco intercingular oblicuo. El análisis morfológico comparativo entre las células vegetativas móviles de la cepa aislada y las tres especies del género descriptas hasta la fecha no reveló diferencias significativas que permitieran determinarla a nivel específico. En cambio, el patrón de desarrollo de surcos longitudinales en el hipocono de células a punto de sufrir mitosis observado en la cepa estudiada, concuerda perfectam