Chlorellaceae

Micractinium pusillum (Fresenius,1858). Usually found in four-celled colonies (only three of the four cells of this colony are seen here). Each cell has two to seven long, delicate setae. Each cell has one cup-shaped plastid with a pyrenoid. 18S ribosomal RNA gene studies place this genus in the Trebouxiophyceae. One of the distinguishing features of trebouxiophytes is metacentric mitosis in which centrioles are located near the metaphase plate of the chromosomes rather than at the spindle poles. Other characteristics include formation of microtubules parallel to the dividing cell wall during cytokinesis (phycoplast). The similar genus, Errerella, has only one spine per cell.Collected from a freshwater pond near Boise, Idaho. July 2005. Phase contrast.

Argusino, Castilla y Len, Espaa

Galende, Castille and Leon, Spain

Encinedo, Castilla y Len, Espaa

San Martin De Castaneda, Castille and Leon, Spain

Dictyosphaerium spec. in mucilaginous envelope. Scale bar indicates 10 m.The specimen was gathered in the wetlands of Nationalpark Unteres Odertal ( 100 km north east of Berlin). The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Universal with Olympus C7070 CCD camera.For permission to use of (high-resolution) images please contact postmaster@protisten.de.

Muelas del Pan, Castille and Leon, Spain

Ribadelago de Franco, Castilla y Len, Espaa

Argusino, Castilla y Len, Espaa

Ribadelago, Castille and Leon, Spain

Galende, Castile and Len, Spain

Dictyosphaerium spec. in mucilaginous envelope. Scale bar indicates 25 m.The specimen was gathered in the wetlands of Nationalpark Unteres Odertal ( 100 km north east of Berlin). The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Universal with Olympus C7070 CCD camera.For permission to use of (high-resolution) images please contact postmaster@protisten.de.

San Martin De Castaneda, Castille and Leon, Spain

Ribadelago de Franco, Castille and Leon, Spain

Ribadelago, Castilla y Len, Espaa

Ribadelago de Franco, Castille and Leon, Spain

Galende, Castile and Len, Spain

This 1971 image depicted a frontal view of a Petri dish culture in which a small colony of Prototheca wickerhamii algal organisms had been cultivated.Created: 1971

At a magnification of 1125X, this photomicrograph revealed the presence of a number of Prototheca wickerhamii algal organisms.Created: 1971

Under a magnification of 1125X, this photomicrograph revealed the presence of numbers of algal organisms, Prototheca wickerhamii, which were found within a tissue specimen. Though categorized taxonomically as an alga, it derives its sustenance as a saprophyte, consuming dead and decaying organic matter. This algal culture was prepared using a lactophenol cotton blue mount fixation technique.Under microscopic analysis, Prototheca spp. resemble a fungal organism, and can therefore, be mistaken when attempting to identify these algae.Similar to the members of the genus Chlorella, Prototheca spp. are heterotrophic, , which means these organisms require carbon in order to thrive, and obtains this nutrient through its consumption of organic substrates. This algal culture was prepared using a lactophenol cotton blue mount fixation technique.Created: 1972

Under a magnification of 500X, this Gridley-stained photomicrograph revealed the presence of numbers of algal organisms, Prototheca wickerhamii, which were found within a specimen of deer tissue. Though categorized taxonomically as an alga, it derives its sustenance as a saprophyte, consuming dead and decaying organic matter.Under microscopic analysis, Prototheca spp. resemble a fungal organism, and can therefore, be mistaken when attempting to identify these algae.Similar to the members of the genus Chlorella, Prototheca spp. are heterotrophic, , which means these organisms require carbon in order to thrive, and obtains this nutrient through its consumption of organic substrates. This algal culture was prepared using a lactophenol cotton blue mount fixation technique.Created: 1972

This photomicrograph depicts the presence of Prototheca wickerhamii in a case of protothecosis.Created: 1971

Note the histopathologic changes in protothecosis of the skin and mucous membrane of the nose due to P. wickerhamii.Created: 1973

This photomicrograph confirms the presence of Prototheca wickerhamii, an achlorophyllic algae.Created: 1972