Dimorphococcus

Dimorphococcus is a genus of fresh water green algae in the family Scenedesmaceae.^[2] It is found as a component of the phytoplankton of freshwater ponds, lakes, and peat bogs. It is widespread, but usually not very common.^[1]

Dimorphococcus
Dimorphococcus lunatus
Scientific classification
Kingdom:	Plantae
Division:	Chlorophyta
Class:	Chlorophyceae
Order:	Sphaeropleales
Family:	Scenedesmaceae
Genus:	Dimorphococcus Braun
Type species
Dimorphococcus lunatus Braun[1]
Species
Dimorphococcus lunatus

Dimorphococcus is usually found in small colonies of multiples of four cells, surrounded by a gelatinous mass. Groups of four cells are further attached to each other via mucilaginous strands, which are the remnants of the mother cell wall.^[3] Cells are kidney-shaped to heart-shaped, 10–25 μm long and 3–8(–15) μm wide. Each cell is uninucleate (containing one nucleus) and has one parietal chloroplast each with one or more pyrenoids.^[1]

Dimorphococcus reproduces asexually via autospores, with four spores produced per mother cell. Autospores are released through a lateral tear in the mother cell wall. After release, the empty cell wall gradually dissolves.^[1]

Taxonomy

Currently, Dimorphococcus is placed in the family Scenedesmaceae, according to molecular phylogenetic analyses.^[4]

One species, Dimorphococcus fritschii, is of uncertain status. The phycologist Chin Chih Jao considered it to have a different structure than other species of Dimorphococcus; accordingly, he placed it into a new genus, Dimorphococcopsis. The species has not been re-investigated and it is possible that the original placement was correct.^[5]