Chloropicophyceae is a class of

green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ( Embryophytes) have emerged deep in the Charophyte alg ...

in the division

Chlorophyta Chlorophyta or Prasinophyta is a taxon of green algae informally called chlorophytes. The name is used in two very different senses, so care is needed to determine the use by a particular author. In older classification systems, it refers to a ...

that, along with

Picocystophyceae ''Picocystis'' is a monotypic genus of green algae, the sole species is ''Picocystis salinarum''. It is placed within its own class, Picocystophyceae in the division Chlorophyta. Structure ''Picocystis salinarum'' cells under normal condition ...

, coincides with the traditional "

prasinophyte The prasinophytes are a group of unicellular green algae. Prasinophytes mainly include marine planktonic species, as well as some freshwater representatives.Sym, S. D. and Pienaar, R. N. 1993. The class Prasinophyceae. In Round, F. E. and Chapman ...

clade VII".

Description

Members of this class are coccoid green cells, with a diameter of 1.5–4 µm, found in marine waters, with one

nucleus Nucleus ( : nuclei) is a Latin word for the seed inside a fruit. It most often refers to: *Atomic nucleus, the very dense central region of an atom * Cell nucleus, a central organelle of a eukaryotic cell, containing most of the cell's DNA Nucl ...

, one

mitochondrion A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is use ...

, and one

chloroplast A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it ...

surrounded by two membranes, containing starch grain; their single chloroplast has

chlorophylls Chlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words , ("pale green") and , ("leaf"). Chlorophyll allow plants to a ...

'' a'' and '' b''; they lack

pyrenoid Pyrenoids are sub-cellular micro-compartments found in chloroplasts of many algae,Giordano, M., Beardall, J., & Raven, J. A. (2005). CO2 concentrating mechanisms in algae: mechanisms, environmental modulation, and evolution. Annu. Rev. Plant Bio ...

and

flagella A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have f ...

; and they have a layered

cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mec ...

. Their

sexual reproduction Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete ( haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote th ...

is unknown.

Taxonomy

In total, this class contains eight newly described species, belonging to two genera. The taxonomy goes as follows :
*Division

Reichenbach 1834 ** Class Chloropicophyceae Lopes dos Santos & Eikrem 2017 *** Order Chloropicales Lopes dos Santos & Eikrem 2017 **** Family Chloropicaceae Lopes dos Santos & Eikrem 2017 ***** Genus ''

Chloropicon ''Chloropicon'' is a genus of green algae in the class Chloropicophyceae. Description Members of this genus are coccoid cells measuring 2–4 µm, characterized by having one green, often crescent-shaped chloroplast shaped with a starch gra ...

'' Lopes dos Santos & Eikrem 2017 ****** ''Chloropicon sieburthii'' Lopes dos Santos & Eikrem 2017 (type species) ****** ''Chloropicon primus'' Lopes dos Santos & Eikrem 2017 ****** ''Chloropicon roscoffensis'' Lopes dos Santos & Eikrem 2017 ****** ''Chloropicon mariensis'' Lopes dos Santos & Eikrem 2017 ****** ''Chloropicon laureae'' Lopes dos Santos & Eikrem 2017 ****** ''Chloropicon maureeniae'' Lopes dos Santos & Eikrem 2017 ***** Genus ''

Chloroparvula ''Chloroparvula'' is a genus of green algae in the class Chloropicophyceae. Description Members of this genus are distinguished from other species of Chloropicophyceae Chloropicophyceae is a class of green algae in the division Chlorophyta ...

'' Lopes dos Santos & Eikrem 2017 ****** ''Chloroparvula pacifica'' Lopes dos Santos & Eikrem 2017 (type species) ****** ''Chloroparvula japonica'' Lopes dos Santos & Eikrem 2017

Phylogeny

In the 2017 article where the new class is described, it is shown as the sister clade of the class

. The internal relationships are shown in the tree below, which is a simplified version of the phylogenetic tree elaborated in the research:

References

{{Taxonbar, from=Q65151860 Chlorophyta Green algae classes