Cylindrospermopsis raciborskii mild skin reactions upon exposure. The last two toxins, anatoxin-a and saxitoxin, are thought to be shellfish neurotoxins. Research has shown that "C. raciborskii" can naturally produce butylated hydroxytoluene, an antioxidant, food additive, and industrial chemical. Domain – Bacteria The Tree of Life contains three Domains: Bacteria, Archaea, and Eukarya. Kingdom – Bacteria Bacteria consists of prokaryotic microorganisms. They were among the first life forms to appear on Earth and appear in a wide variety of habitats. Phylum – Cyanobacteria This phylum is characterized by their ability to obtain energy through photosynthesis. They are often called the blue-green algae stemming
Brown algae preserve only a flattened outline, without the microscopic features that permit the major groups of multicellular algae to be reliably distinguished. Among the brown algae, only species of the genus "Padina" deposit significant quantities of minerals in or around their cell walls. Other algal groups, such as the red algae and green algae, have a number of calcareous members. Because of this, they are more likely to leave evidence in the fossil record than the soft bodies of most brown algae and more often can be precisely classified. Fossils comparable in morphology to brown algae are known from strata as