Ankyra is a genus of green algae in the family Characiaceae. This genus of algae is closely related to Atractomorpha and Sphaeroplea. They are found in stagnant waters.
Bryopsidella is a genus of green algae in the family Bryopsidaceae.
Pseudochlorella signiensis is a species of green algae in the family Koliellaceae. Pabia signiensis, the only species in the genus Pabia, is regarded as a synonym. Pabia was sunk into Pseudochlorella in 2016.
Chaetomnion is a genus of green algae in the family Chaetophoraceae. The only known species in the genus is Chaetomnion pyriferum.
Emergococcus is a genus of green algae, in the family Chlorococcaceae. It contains a single species, Emergococcus lucens. It is neustonic in fresh water.
Sykidion is a genus of green algae. Pseudoneochloris is a synonym of this genus. As of March 2022, Sykidion was the only genus in the family Sykidiacaeae, which was the only family in the order Sykidiales.
The Mesostigmatophyceae are a class of basal green algae found in freshwater. In a narrow circumscription, the class contains a single genus, Mesostigma. AlgaeBase then places the order within its circumscription of Charophyta. A clade containing Chlorokybus and Spirotaenia may either be added, or treated as a sister, with Chlorokybus placed in a separate class, Chlorokybophyceae. When broadly circumscribed, Mesostigmatophyceae may be placed as sister to all other green algae, or as sister to all Streptophyta.
Chlorokybus is a multicellular (sarcinoid) genus of basal green algae or charophyte. It has been classified as the sole member of the family Chlorokybaceae, which is the sole member of the order Chlorokybales, in turn the sole member of the class Chlorokybophyceae. It grows on soil and rock surfaces, and is rare.
Mesostigma is a genus of unicellular biflagellate freshwater green algae, with a single species Mesostigma viride, covered by an outer layer of basket‐like scales instead of a cell wall. AlgaeBase classifies it as the only genus in the family Mesostigmataceae, the only family in the order Mesostigmatales, the only order in the class Mesostigmatophyceae. It is now considered to be one of the earliest diverging members of green plants/algae (Viridiplantae).
The Rivulariaceae are a family of cyanobacteria within the Nostocales in which the filaments (trichomes) are tapered from wider at the base to narrower at the tip.
