Spatio-temporal Variation of Harmful Planktonic Microalgae and Cyanobacteria Along the Central Coast of Campeche, Southeastern Gulf of Mexico

To describe the phytoplankton species composition, spatio-temporal distribution and habitats during different seasons along the central coast of the state of Campeche, Mexico, southeastern Gulf of Mexico, eight shallow-water (ca 1 m) sites from the city of Campeche Southwest to Villamar were monitored monthly from September 2016 to June 2017 by taking water-bottle samples. Average water temperature varied between 22.2 and 30.9°C and average salinity between 26.6 and 35.0. The Kolmogorov-Smirnov test, the Bartlett's test and canonical correspondence analyses were applied. Sixteen potentially harmful microalgal species were found: five species are bloom-forming, nine are potentially toxic to humans, and two affect aquatic organisms. At all sampling sites, massive algal proliferations occurred in June (beginning of rainy season) caused by the dinoflagellates Heterocapsa sp. (2.6 × 10⁵ cells/L) and Blixaea quinquecornis (2.0 × 10⁴ cells/L) and from October to March (windy season) by the cyanobacterium Trichodesmium sp. (2.6 × 10⁵ cells/L).