The Pleurocapsales are an order of coccooid cyanobacteria. Pleurocapsales are characterized by having boocytes, specialized cells where multiple fission takes place.[2]
Their ecology is mainly endolytic and calcareous, they are found inside rocks and in low light conditions.[3] Pleurocapsales were thought to be related to Chroococcidiopsis but recent work with phylogenetics of the 16S rDNA gene has shown that Chroococcidiopsis belongs to its own order Chroococcidiopsidales.[4]
Some genera within Pleurocapsales form pseudo-ramifications such as Pleurocapsa sp., Odorella sp, and all the genera within the Hyellaceae family.[5]
Historically, the order Pleurocapsales has been one of the least studied orders of cyanobacteria, due to its endolithic ecology making them difficult to observe.[6]