Cryptoglena | |
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Scientific classification | |
Domain: | Eukaryota |
Phylum: | Euglenozoa |
Class: | Euglenida |
Family: | Kinetoplastida |
Genus: | Cryptoglena Ehrenberg, 1831. |
Cryptoglena (/ˌkɹɪptoʊˈgliːnə/) is a genus of photosynthetic euglenids that was first described in 1831 by Christian Gottfried Ehrenberg.[1] Today, its circumscription is controversial: Bicudo and Menezes[2] consider twenty-one species as Cryptoglena, of which, nine are uncertain. Cryptoglena species are water-based, living in both freshwater and marine environments. They are biflagellated, with one internal flagellum and one external flagellum, which allows movement through environments as demonstrated by Kim and Shin[3] in the species C. pigra. The cells of Cryptoglena resemble a coffee bean, as they have a groove that runs the length of the cell on one side and makes them U-shaped in cross section. They are ovoid in shape and are small, with the larger cells being on average 25 x 15 μm.[4] After being first described in 1831, little work was done on the genus until the late 1970s and early 1980s, after the scanning electron microscope completed development and was implemented into laboratories.[5] Work then proceeded with the developments of molecular biology, which allows for classifications based on DNA sequences. For Cryptoglena the main DNA used for classification are small subunit (SSU) and large subunit (LSU) rDNA.[4]