A Kryptoperidiniaceae species (Dinophyceae: Peridiniales) blooming in coastal Yucatan waters, Gulf of Mexico

Abstract

A small, photosynthetic Peridiniales species caused an intense bloom (up to 3.75×107 cells·l-1) in the marina of Sisal on the northern Yucatan Peninsula coast, SE Gulf of Mexico, in August 2010. The salinity was 32.4, and the water temperature was 29.5 oC. The cells were 12.5-23.7 μm long (19.02±2.03 μm), 8.7-18.7 μm wide (15.45± 2.19 μm) and 7.5-12.5 μm deep (dorsoventral length; 9.63±1.21 μm), the length/ width ratio was 1.17±0.13 and the width/depth ratio 1.83±0.22 (n=200). The species had a thecal plate formula of Po, X, cp, 4', 2a, 6", 5c, PC, 4s, 5"', 2"". The taxon was assigned to the family Kryptoperidiniaceae, although a second (eukaryotic) nucleus was not observed, sharing its thecal features with both Kryptoperidinium and Durinskia. In subsequent years, it was occasionally found at other sites along the Yucatan coast and possibly represents a recent invasion of the southern Gulf of Mexico, preferring semi-enclosed water bodies.