Chlorellaceae are a family of green algae in the order Chlorellales.[1] About 250 species are currently accepted in the family. Members of the family are distributed worldwide and are common in a variety of freshwater, terrestrial and marine environments.[2]
Members of the family Chlorellaceae are important ecologically, mainly as primary producers.[2] Algae such as Chlorella are important model organisms for plant physiology and biochemistry, because of they are easy to cultivate and grow rapidly.[3] Additionally, many members are rich in lipids, carbohydrates and vitamins, making them of interest in the field of biotechnology.[2] Meanwhile, genera such as Prototheca are of clinical significance as pathogens of humans and other animals.[4]
Description
Members of Chlorellaceae are morphologically diverse and include solitary and colonial forms. Traditionally, the family was circumscribed based on the mode of reproduction (productin of autospores), and the family was defined around the type genusChlorella, which is generally solitary and consists of spherical cells. However, based on molecular evidence, a number of genera have been moved into Chlorellaceae that differ significantly in morphology; these include Actinastrum (elongate cells in colonies), Micractinium (spherical cells with bristles), and Didymogenes (colonial cells with a thick mucilaginous envelope).[5] Cells generally contain a single chloroplast with a pyrenoid.
In addition to autotrophic members that contain a chloroplast, the family includes genera which have lost the ability to photosynthesize are therefore heterotrophic. These genera, namely Prototheca and Helicosporidium, are colorless, single-celled organisms that resemble yeast, and are opportunistic pathogens of animals.[4]
Genera
As of 2025, AlgaeBase includes the following genera:[6]
Not all genera are included, as some (e.g. Cylindrocelis, Palmellochaete, etc.) have not been studied using molecular methods. In addition, some genera such as Geminella appear to cluster outside of Chlorellales.[17]
^Krivina, E. S.; Temraleeva, A. D. (2020). "Identification Problems and Cryptic Diversity of Chlorella-Clade Microalgae (Chlorophyta)". Microbiology. 89 (6): 720–732. doi:10.1134/S0026261720060107.
^ abMalavasi, Veronica; Škvorová, Zuzana; Němcová, Yvonne; Škaloud, Pavel (2022). "Laetitia sardoa gen. & sp. nov., a new member of the Chlorellales (Trebouxiophyceae, Chlorophyta) isolated from Sardinia Island". Phycologia. 61 (4): 375–383. Bibcode:2022Phyco..61..375M. doi:10.1080/00318884.2022.2054252.
^Krivina, Elena; Portnov, Aleksey; Temraleeva, Anna (2024). "A description of Aliichlorella ignota gen. et sp. nov. and a comparison of the efficiency of species delimitation methods in the Chlorella -clade (Trebouxiophyceae, Chlorophyta)". Phycological Research. 72 (3): 180–190. doi:10.1111/pre.12551.
^Song, Huiyin; Liu, Xudong; Hu, Yuxin; Wang, Qinghua; Long, Jijian; Liu, Guoxiang; Hu, Zhengyu (2018). "Coronacoccus hengyangensis gen. et sp. nov., a new member of Chlorellaceae (Trebouxiophyceae, Chlorophyta) with radiococcacean morphology". Phycologia. 57 (4): 363–373. Bibcode:2018Phyco..57..363S. doi:10.2216/17-65.1.
^Krienitz, Lothar; Bock, Christina; Kotut, Kiplagat; Pröschold, Thomas (2012). "Genotypic diversity of Dictyosphaerium-morphospecies (Chlorellaceae, Trebouxiophyceae) in African inland waters, including the description of four new genera". Fottea. 12 (2): 231–253. doi:10.5507/fot.2012.017.
^Temraleeva, Anna; Krivina, Elena; Boldina, Olga (2022). "Edaphochloris, gen. nov.: A new genus of soil green algae (Trebouxiophyceae, Chlorophyta) with simple morphology". Plant Systematics and Evolution. 308 (1): 4. Bibcode:2022PSyEv.308....4T. doi:10.1007/s00606-021-01795-8.
