''Navicula'' is a
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of boat-shaped
diatom
A diatom (Neo-Latin ''diatoma'') is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's B ...
(single-celled photosynthetic organisms), comprising over 1,200 species, though many ''Navicula'' species likely do not belong in the genus strictly speaking.
''Navicula'' is Latin for "small ship", and also a term in English for a boat-shaped
incense
Incense is an aromatic biotic material that releases fragrant smoke when burnt. The term is used for either the material or the aroma. Incense is used for aesthetic reasons, religious worship, aromatherapy, meditation, and ceremonial reasons. It ...
-holder.
Oxford English Dictionary
The ''Oxford English Dictionary'' (''OED'') is the principal historical dictionary of the English language, published by Oxford University Press (OUP), a University of Oxford publishing house. The dictionary, which published its first editio ...
, "Navicula. 3" ''Navicula'' is a
cosmopolitan
Cosmopolitan may refer to:
Internationalism
* World citizen, one who eschews traditional geopolitical divisions derived from national citizenship
* Cosmopolitanism, the idea that all of humanity belongs to a single moral community
* Cosmopolitan ...
genus and species are present in both freshwater and marine environments, typically attached to surfaces (i.e.
benthic
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...
).
Description
''Navicula'' species are
pennate diatoms. Their valves are typically elliptical, though some species have more pinched ends than others. ''Navicula'' cells have two
chloroplasts
A chloroplast () is a type of membrane-bound organelle, organelle known as a plastid that conducts photosynthesis mostly in plant cell, plant and algae, algal cells. Chloroplasts have a high concentration of chlorophyll pigments which captur ...
, one along each side of the valve along the girdle bands.
Mobility
''Navicula'' diatoms are highly motile and move through a gliding movement This is done through excretion of
extracellular polymeric substances (EPS). One form of EPS surrounds the outside of the cell and another is excreted through a slit in the
frustule called a raphe, allowing the cell to glide along a track.
References
External links
''Navicula'' Image (Missouri State University)*
ttps://web.archive.org/web/20060818063256/http://vis-pc.plantbio.ohiou.edu/algaeimage/pages/Navicula.html Bacillariophyceae - ''Navicula'' Ohio University*
*
File:Navicula tripunctata 2.jpg, ''Navicula tripunctata''
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 ...
, scale= 50 μm
File:Lyrella hennedy 1600x contrast invertion.jpg, ''Lyrella hennedy''
File:Navicula oblonga - 160x - Seitensicht (13465052133).jpg, ''Navicula oblonga''
File:Navicula oblonga - 160x - Schrägsicht (13464954365).jpg, ''Navicula oblonga''
Diatom genera
{{Diatom-stub