Sphaeropleales
Encyclopedia
In taxonomy
, the Sphaeropleales are an order
of green algae that used to be called Chlorococcales
. This order includes vegetatively non-motile unicellular or colonial taxa that have biflagellate zoospore
s with flagella that are directly opposed in direction (the DO arrangement): Sphaeroplea
, Atractomorpha, Neochloris
, Hydrodictyon, and Pediastrum
. All of these taxa have basal body core connections.
With an increase in the number of taxa for which sequence data are available, there is evidence of an expanded DO clade that includes additional zoosporic (Bracteacoccus
, Schroederia
) and some strictly autosporic genera such as Ankistrodesmus
, Scenedesmus
, Selanastrum, Monoraphidium
, and Pectodictyon
.
Monophyly of the DO clade is generally weakly supported by phylogenetic analysis of molecular data, even those that have used data from two genes.
Alpha taxonomy
Alpha taxonomy is the discipline concerned with finding, describing and naming species of living or fossil organisms. This field is supported by institutions holding collections of these organisms, with relevant data, carefully curated: such institutes include natural history museums, herbaria and...
, the Sphaeropleales are an order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
of green algae that used to be called Chlorococcales
Chlorococcales
Chlorococcales is an order of green algae in the class Chlorophyceae. Individual specimens are sometimes found in soil, but mostly in fresh and marine waters...
. This order includes vegetatively non-motile unicellular or colonial taxa that have biflagellate zoospore
Zoospore
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some algae, bacteria and fungi to propagate themselves.-Flagella:...
s with flagella that are directly opposed in direction (the DO arrangement): Sphaeroplea
Sphaeroplea
In taxonomy, Sphaeroplea is a genus of algae, specifically of the Sphaeropleaceae.-Scientific databases:* * *...
, Atractomorpha, Neochloris
Neochloris
Neochloris is a genus of algae, in the family Chlorococcaceae.-Scientific databases:* * *...
, Hydrodictyon, and Pediastrum
Pediastrum
Pediastrum is a genus of algae, in the family Hydrodictyaceae. It is a nonmotile coenobial green alga that inhabits freshwater environments.-Reproduction:...
. All of these taxa have basal body core connections.
With an increase in the number of taxa for which sequence data are available, there is evidence of an expanded DO clade that includes additional zoosporic (Bracteacoccus
Bracteacoccus
Bracteacoccus is a genus of algae, in the family Chlorococcaceae.-Scientific databases:* * *...
, Schroederia
Schroederia
Schroederia is a genus of algae, in the family Chlorococcaceae.-Scientific databases:* * *...
) and some strictly autosporic genera such as Ankistrodesmus
Ankistrodesmus
In taxonomy, Ankistrodesmus is a genus of algae, specifically of the Selenastraceae.-Scientific databases:* * *...
, Scenedesmus
Scenedesmus
Scenedesmus is a genus of algae, specifically of the Chlorophyceae. They are colonial and non-motile....
, Selanastrum, Monoraphidium
Monoraphidium
In taxonomy, Monoraphidium is a genus of algae, specifically of the Selenastraceae.-Scientific databases:* * *...
, and Pectodictyon
Pectodictyon
In taxonomy, Pectodictyon is a genus of algae, specifically of the Scenedesmaceae.-Scientific databases:* * *...
.
Monophyly of the DO clade is generally weakly supported by phylogenetic analysis of molecular data, even those that have used data from two genes.