''Monas'' is a genus of
Chrysophyceae, described by
Otto Friedrich Müller
Otto Friedrich Müller, also known as Otto Friedrich Mueller (2 November 1730 – 26 December 1784) was a Denmark, Danish natural history, naturalist and scientific illustrator.
Biography
Müller was born in Copenhagen. He was educated for the ch ...
in
1773 as a group of
Infusoria. Throughout time, it represented an aggregate genus.
Taxonomic history
Many organisms were transferred to this genus, and most ''Monas'' spp. have later been synonymised with or integrated in other genera. The organisms once affiliated with ''Monas'' spp. truly belong to all major eukaryotic lineages (
Opisthokonta,
Amoebozoa
Amoebozoa is a major Taxonomy (biology), taxonomic group containing about 2,400 described species of Amoeba, amoeboid protists, often possessing blunt, fingerlike, Pseudopod#Morphology, lobose pseudopods and tubular mitochondrial cristae. In trad ...
,
Rhizaria,
Archaeplastida,
Stramenopiles
The stramenopiles, also called heterokonts, are Protist, protists distinguished by the presence of stiff tripartite external hairs. In most species, the hairs are attached to flagella, in some they are attached to other areas of the cellular sur ...
,
Alveolata,
Cryptophyta
The cryptomonads (or cryptophytes) are a Class (biology), superclass of algae, most of which have chloroplast, plastids. They are traditionally considered a Division (taxonomy), division of algae among phycologists, under the name of Cryptophyta ...
,
Excavata), and even to prokaryotic lineages.
The genus was also included in other groups, as in
Mastigophora or
Flagellata. The current practice is the (questionable) synonymous use, based on morphological similarity, of the generic names ''Monas'' (mostly used in the east-Asian literature) and ''Spumella'' (synonymously used in the European and American literature) as unpigmented biflagellates in
Chrysophyceae. However, there is a conflict between the morphological and molecular investigations. The present-day taxon ''Monas''/''Spumella'' is still
polyphyletic
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...
, comprising at least three to five lineages, and evidence about the identity of the
type species
In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...
of ''Monas'' is missing.
[
This problem in the circumscription of groups, using the practical morphological (or taxonomic) species concept or the biological species concept (based on the degree of molecular similarity), is also faced in the taxonomy of other microorganisms,][ and microalgae (e.g., ]Chlorococcales
Chlorococcales is a formerly recognized Order (biology), order of green algae in the Class (biology), class Chlorophyceae. , the type family Chlorococcaceae was placed in the order Chlamydomonadales.
Conventionally, many groups of coccoid green ...
).
References
{{Taxonbar, from=Q18180890
Golden algae genera
Chrysophyceae
Taxa named by Otto Friedrich Müller