Domain: EukaryotaAlexandrium. ©Yasuwo Fukuyo

Kingdom: Protozoa

Phylum: Dinophyta

Class: Dinophyceae

: Gonyaulacales

Family: Gonyaulacaceae

Genus: Gonyaulax

Gonyaulax catenella

                                                                                                                                                                                                                                                                                       ©Yasuwo Fukuyo

Eukarya: Gonyaulax is a protist, and thus classified as a eukaryote. It possesses membrane bound organelles and a true nucleus. Check out another eukaryotic organisms such as Lilly of the Valley and Solenodon paradoxus!

Protozoa: This eukaryotic kingdom contains many unicellular organisms. Its singular form protozoon follows the Greek meaning of proto= first and  zoon=animal. Ultimately meaning first animal. Under this kingdom various other supergroups can be found, categorizing a vast variety of organisms. These can range from multicellular red alga stalks to unicellular phytoplankton. Gonyaulax catenella is classified as such because of it's eukaryotic trait, ability to move, and some organelles such as cholorplasts. with many unusual characteristics not found in other groups.

Dinophyta: G. catenella is grouped within the dinophyta because it is a single celled eukaryote. It has also adopted diverse modes of nutrition, such as predation, photoautotrophy, and intracellular parasitism.  The phylum Dinophyta is a result of a single secondary endosymbiosis between a bikont and a red alga. Gonyaulax catenella are classified under dinophyta because of the cells photosynthetic ability, the presence of cellulose plates,  flagella.

Dinophyceae: General Thecal Cell. © 2004 Mona Hoppenrath.
Dinophyceae are dinoflagellate organisms that live in all types of aquatic ecosystems. Many of the species in the group are photosynthetic. Gonyaulax catenella is one of those species. The others are exclusively heterotrophic. There are members of the phytoplankton and zooplankton of marine and freshwater ecosystems in this group. The nucleus of a large majority of dinoflagellates is different from other eukaryotic nuclei—dinokaryon.
Dinokarya lack a nucleosomse,
and DNA content is
 larger than that of
other eukaryotic cells.
                                         © 2004 Mona Hoppenrath.     

Gonyaulacales They are armored, while almost all of them contain chloroplasts, only some of the under the order of Gonyaulaces can produce toxins and red tides. They are distinguished by the arrangement and number of thecal plates and how the tabulation is derived. Thus far, 344 species have been categorized as a part of Gonyaulacales. The family Gonyaucaceae follows these same characteristics.
                                 Ceratium arcticum. ©Yasuwo Fukuyo
©Yasuwo Fukuyo

Gonyaulax: Gonyaulax catenella are single celled aquatic organisms that are characterized by closely fitting cellulose plates and have two flagella. One extends backward, and the other in an encircling groove. They don't have an stigma and contain chromatophore pigments that range from yellow to brown. Some have an apical horn or posterior spines. Take a look at the Blue Ringed Octopus to learn about its chromatophore pigments!

Gonyaulax catenella:  These organisms are aElectromagnic photo of Gonyaulax catenella © 1999  Allison Arnold and Monica Draghici
toxic planktonic form of Gonyaulax. Sometimes they are abundant enough to color water and cause red tide. Humans my also be poisoned by marine life that have ingested G. catenlla. They have a rounded apex and the thecal plates are thin and lightly porulated. The nucleus is U- shaped. Gonyaulax catenella is synonymous to Alexandrium catenella. Throughout the rest of this website, Alexandrium and Gonyaualx catenlla will be used interchangeably.

                                                                                                                 © 1999 Allison Arnold and Monica Draghici
     In this polyphyletic tree, it shows the lineage of the evolution of plastida. It is generally stated that all organisms with chloroplasts and or plastids share a single ancestor that engulfed a cyanobacterium 600-1600 million years ago. In protists such as Euglenozoa, chloroplasts have evolved through a secondary endosymbiosis.  In this situation the chloroplast may form with three or four membrane layers. Dinoflagellates also have three membrane layers around their chloroplast. This tree shows that dinoflagellates have ancestors of cyanobacteria on a cellular level. They are also related to other protists through a red alga, and thus a dinoflagellates descended from the kingdom Alveolates. Ultimately this tree shows dinoflagellates, meaning Gonyaulax catenella having an algal and cyanobacterium ancestors.

Clastic Tree of Plastid evolution © 2008 Pearson Benjamin Cummings
© 2008 Pearson Benjamin Cummings

Click here to check out a cyanobacterium ancestor!

Interested in knowing where Gonyaulax catenella resides? Click to follow the Habitat page.