Chaetocerotales

Chaetocerotales is an order of marine diatoms, which are single-celled algae belonging to the division Bacillariophyta. These diatoms are characterized by their distinctive, often elaborate, siliceous cell walls called frustules. A key feature of the Chaetocerotales is the presence of prominent setae, which are long, bristle-like spines that extend from the frustule. These setae can aid in flotation and may also play a role in defense against grazing. The frustules are typically ornamented with complex patterns of pores and ribs.

Members of the Chaetocerotales are found in a wide range of marine environments, from polar regions to the tropics, and are particularly abundant in coastal waters and upwelling zones. They are important primary producers, forming a significant part of phytoplankton communities and contributing to global carbon cycles. Many species are known for their rapid growth rates, especially under nutrient-rich conditions. The order includes several ecologically significant genera, such as Chaetoceros and Bacteriastrum. Some species can form large colonies, linked together by their setae. Reproduction occurs both asexually through cell division and sexually. Chaetocerotales are often studied in the context of oceanography, ecology, and climate change research due to their sensitivity to environmental conditions.