Proliferation of Levanderina fissa and Polykrikos hartmannii (dinophyceae: Gymnodiniales) in Bahía de La Paz, Gulf of California, México.

On 19–20 August 2014, a moderate proliferation of dinoflagellates was detected in the southwestern part of Bahía de La Paz. The phytoplankton community within this red tide was composed of 60 microalgae taxa and was characterized by the presence of unarmored dinoflagellates such as Levanderina fissa and Polykrikos hartmannii. The proliferation occurred during low tide after a period of windy and rainy days. Densities of L. fissa varied from 163 to 265 × 103 cells L–1 and for P. hartmannii varied from 16 to 33 × 103 cells L–1. Low densities were estimated on September and October   samplings. Both species showed a great variation both in size and form. As part of the phytoplankton species composition during this proliferation, two taxa of dinoflagellates are new records for the Pacific coast of Mexico (Ankistrodinium   semilunatum and Sclerodinium calyptroglyphe), one in the Gulf of California (Pronoctiluca acuta), and one in the Bahía de La Paz (Prorocentrumrobustum). Cyanobacteria were an important group observed during this proliferation. The symbiotic association between a cyanobacterium Synechococcus sp., the stramenopile protist Solenicola setigera, and the diatom Leptocylindrus mediterraneus was observed for the first time in this bay.