''Lepocinclis'' is a genus of
algae
Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...
belonging to the family
Phacaceae.
The genus has a
cosmopolitan distribution
In biogeography, a cosmopolitan distribution is the range of a taxon that extends across most or all of the surface of the Earth, in appropriate habitats; most cosmopolitan species are known to be highly adaptable to a range of climatic and en ...
,
and is primarily part of the
plankton
Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...
in
freshwater
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...
habitats (rarely brackish ones).
[
]
Description
''Lepocinclis'' consists of single, free-swimming cells, with the flagella
A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many pr ...
, eyespot (stigma), and flagellar swelling similar to that of ''Euglena
''Euglena'' is a genus of Unicellular organism, single-celled, flagellate eukaryotes. It is the best-known and most widely studied member of the class Euglenoidea, a diverse group containing some 54 genera and at least 200 species. Species of '' ...
''.[ The cells are rigid or semi-rigid (they may bend somewhat, but are not ]metabolic
Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the ...
).[ Cells often with a tapering posterior spine; the cell is surrounded by a pellicle with spiral striations. Cells are typically filled with numerous small, discoid ]chloroplast
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 ...
s without pyrenoids, which give the cell a green color.[ A few species have secondarily lost their chloroplasts, and are therefore colorless. Cells are also filled with paramylon grains, of two different sizes (dimorphic); the large paramylon grains are ring-shaped or rod-shaped.][
]
Taxonomy
The circumscription and species-level taxonomy of ''Lepocinclis'' has changed significantly with molecular phylogenetic
Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...
analyses.[ Another change involved the genus ''Cyclidiopsis'', which differed from ''Lepocinclis'' '']sensu stricto
''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular c ...
'' in having colorless cells (no chloroplasts). ''Cyclidiopsis'' was found to be included within the clade of ''Lepocinclis'', and thus made a synonym.
Species delimitation involves morphological characters such as the shape and size of cells, and the number and shape of paramylon grains.
References
{{Taxonbar, from=Q2685261
Euglenozoa
Euglenozoa genera