Charales is an order of freshwater

green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ...

in the division

Charophyta Charophyta () is a paraphyletic group of freshwater green algae, called charophytes (), sometimes treated as a division, yet also as a superdivision. The terrestrial plants, the Embryophyta emerged deep within Charophyta, possibly from terres ...

, class

Charophyceae Charophyceae is a class of charophyte green algae. AlgaeBase places it in division Charophyta. Extant (living) species are placed in a single order Charales, commonly known as "stoneworts" and "brittleworts". Fossil members of the class may be p ...

, commonly known as stoneworts. Depending on the treatment of the genus '' Nitellopsis'', living (extant) species are placed into either one family (

Characeae Characeae is a family of freshwater green algae in the order Charales, commonly known as stoneworts. They are also known as brittleworts or skunkweed, from the fragility of their lime-encrusted stems, and from the foul odor these produce when ste ...

) or two (Characeae and Feistiellaceae). Further families are used for fossil members of the order.

Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

established the genus '' Chara'' in 1753. Chara1

Taxonomy

The higher level classification of

was unsettled .

AlgaeBase AlgaeBase is a global species database of information on all groups of algae, both seaweed, marine and freshwater algae, freshwater, as well as sea-grass. History AlgaeBase began in March 1996, founded by Michael D. Guiry, Michael Guiry. Text ...

places Charales within the class

and its

circumscription Circumscription may refer to: * Circumscribed circle * Circumscription (logic) *Circumscription (taxonomy) * Circumscription theory, a theory about the origins of the political state in the history of human evolution proposed by the American anthr ...

of the division

Families

The number of families and their division into genera varies. , AlgaeBase accepts two families containing some extant species and four families containing only fossil species: *

S.F.Gray * Feistiellaceae Schudack *† Aclistocharaceae X.G.Zhou (may be included in Characeae) *† Atopocharaceae R.E.Peck (may be included in Clavatoraceae) *† Clavatoraceae Pia *† Porocharaceae Grambast AlgaeBase places the genus '' Nitellopsis'', which has both extant and extinct species, in the family Feistiellaceae. Other sources place ''Nitellopsis'' in the family Characeae, with Feistiellaceae containing only fossil species, so that all extant species are in the family Characeae. The

Interim Register of Marine and Nonmarine Genera The Interim Register of Marine and Nonmarine Genera (IRMNG) is a taxonomic database which attempts to cover published genus names for all domains of life (also including subgenera in zoology), from 1758 in zoology (1753 in botany) up to the pre ...

accepts a further three extinct families: *† Eocharaceae Grambast *† Palaeocharaceae Pia *† Raskyellaceae Grambast

Fossil record

Body fossils of representatives of the order Charales do exist, but are rare. The fossil record of the Charales consists mostly of gyrogonites, that is, calcified fructifications or, more exactly, calcified spiral cells surrounding the oospores. It may be noted that the gyrogonites are studied by

palaeontologists Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

, but not often destroyed (using acids) during neontological research to liberate the oospores. The oldest known representative of the Charales is ''Eochara wickendenii'' Choquette from the Middle Devonian. The family Characeae starts dominating the fossil assemblages in the

Paleogene The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...

or perhaps already in the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

References

External links

Images of Charales''Chara curta'' in Ireland
{{Taxonbar, from=Q14920463 Charophyta Charophyta orders

Taxonomy

Families

Fossil record

References

Further reading

External links