''Golenkinia'' is a genus 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 alga as ...

first described in 1894 by

Robert Chodat Robert Hippolyte Chodat (4 June 1865, Moutier – 28 April 1934) was a Swiss botanist and phycologist who was a professor and director of the botanical institute at the University of Geneva. He studied medicine and botany at Geneva, where he was l ...

. The genus is named for the Russian phycologist Mikhail Iljitsch Golenkin. ''Golenkinia'' species live in

fresh water Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include ...

(including bodies of black water such as Winyah Bay) and are found around the world.

Description

Members of ''Golenkinia'' are spherical unicellular organisms with numerous radiating spines. Their

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 mech ...

s are notably thick, which distinguishes them from members of the genus '' Golenkinopsis''. They contain a single walled cup-shaped

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 in ...

, which in turn contains a pyrenoid in its base. The pyrenoid is typically sheathed in starch. Species of ''Golenkinia'' are typically solitary and do not form colonies or coenobia except under laboratory conditions. Their slender spines may become entangled, creating the false impression that the algae have formed a colony.

Taxonomic status

The precise taxonomic status of ''Golenkinia'' is somewhat unclear due to the large number of revisions it has undergone. It has traditionally been classed with other round, spine-bearing green algae, many of which are now assigned to the

class Class or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used differentl ...

Trebouxiophyceae. In 1982, Hanuš Ettl and Jiří Komárek placed ''Golenkinia'' with '' Chlorotetraedron'' and '' Polyedriopsis'' in the family

Neochloridaceae Neochloridaceae is a family of green algae in the order Sphaeropleales.See the NCBI The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institute ...

, under the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

Sphaeropleales Sphaeropleales is an order of green algae that used to be called Chlorococcales. The order includes some of the most common freshwater planktonic algae such as ''Scenedesmus'' and ''Pediastrum''. The Spaeropleales includes vegetatively non-motile ...

. In 1983, Komárek and

Bohuslav Fott Bohuslav ( uk, Богуслав, yi, באָסלעוו or ''Boslov'') is a city on the Ros River in Obukhiv Raion, Kyiv Oblast (province) of Ukraine. Population: . It hosts the administration of Bohuslav urban hromada, one of the hromadas of Ukra ...

created the family

Golenkiniaceae ''Golenkinia'' is a genus of green algae first described in 1894 by Robert Chodat. The genus is named for the Russian phycologist Mikhail Iljitsch Golenkin. ''Golenkinia'' species live in fresh water (including bodies of black water such a ...

to contain unicellular algae with round cells that had spines on the

. The genera ''Golenkinia'' and ''Polyedriopsis'' were placed within it. Subsequent analysis of

18S rDNA 18S ribosomal RNA (abbreviated 18S rRNA) is a part of the ribosomal RNA. The S in 18S represents Svedberg units. 18S rRNA is an SSU rRNA, a component of the eukaryotic ribosomal small subunit ( 40S). 18S rRNA is the structural RNA for the small ...

in 2003 has found that ''Golenkinia'' and ''Polyedriopsis'' are not in fact closely related. The same research assigned ''Golenkinia'' to the order Chlamydomonadales. Further analysis in 2015 found that ''Golenkinia'' was loosely related to ''Jenufa'' and ''

Treubaria ''Treubaria'' is a genus of green algae in the family Treubariaceae. The genus was circumscribed by Charles Jean Bernard in Protococ. Desmid. Eau Douce 5-6, 12, 169 in 1908. The genus name of ''Treubaria'' is in honour of Melchior Treub (1851� ...

'', all together possibly representing a branch in Chlamydomonadales that would be a sister

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

to order Sphaeropleales. This proposed clade remains unnamed, and its taxonomy is still not completely clear, despite further rDNA analysis performed in 2017. Because of the frequent changes to its classification, some databases still show ''Golenkinia'' belonging to Golenkiniaceae.

References

External links

{{Taxonbar, from=Q5580468 Chlamydomonadales Chlamydomonadales genera