page_title: Zygnemataceae
section_title: References
hierarchical_section_title: Zygnemataceae / References
context_page_description: The Zygnemataceae are a family of filamentous or unicellular, uniseriate green algae. The filaments are septated and reproduction is by conjugation; Spirogyra is commonly used in schools to demonstrate this kind of reproduction. The family is notable for its diversely shaped chloroplasts, such as stellate in Zygnema, helical in Spirogyra, and flat in Mougeotia. The Zygnemataceae are cosmopolitan, but though all generally occur in the same types of habitats, Mougeotia, Spirogyra, and Zygnema are by far the most common; in one study across North America, 95% of the Zygnemataceae collected were in these three genera. Classification and identification is primarily by the morphology of the conjugation, which is somewhat rare to find in natural populations of permanent water bodies; when in the vegetative state, the rarer genera resemble the three most common, and are often mistaken for them and catalogued as such. Conjugation can be induced in low-nitrogen culture. While they occupy many habitats, in North America all are found solely in freshwater or subaerial habitats.
context_section_description: Guiry, M.D. (2013). Taxonomy and nomenclature of the Conjugatophyceae (=Zygnematophyceae). Algae. An International Journal of Algal Research 28: 1-29.
  McCourt et al., 1986, as reported in Wehr, 2003, pg. 363
  Wehr, John D. and Sheath, Robert G. Freshwater Algae of North America, pg. 363.
  Gitzendanner, Matthew A.; Soltis, Pamela S.; Wong, Gane K.-S.; Ruhfel, Brad R.; Soltis, Douglas E. (2018). "Plastid phylogenomic analysis of green plants: A billion years of evolutionary history". American Journal of Botany. 105 (3): 291–301. doi:10.1002/ajb2.1048. ISSN 0002-9122. PMID 29603143.
caption: Spirogyra mats in a still pond.
exif: {"Image Make": "Canon", "Image Model": "Canon PowerShot A200", "Image Orientation": "Horizontal (normal)", "Image XResolution": "180", "Image YResolution": "180", "Image ResolutionUnit": "Pixels/Inch", "Image DateTime": "2005:04:09 17:06:17", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "196", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "180", "Thumbnail YResolution": "180", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "2036", "Thumbnail JPEGInterchangeFormatLength": "4647", "EXIF ExposureTime": "1/200", "EXIF FNumber": "14/5", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2005:04:09 17:06:17", "EXIF DateTimeDigitized": "2005:04:09 17:06:17", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "5", "EXIF ShutterSpeedValue": "245/32", "EXIF ApertureValue": "97349/32768", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "97349/32768", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, auto mode", "EXIF FocalLength": "5", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1024", "EXIF ExifImageLength": "768", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "1024", "Interoperability RelatedImageLength": "768", "EXIF InteroperabilityOffset": "1412", "EXIF FocalPlaneXResolution": "1024000/173", "EXIF FocalPlaneYResolution": "76800/13", "EXIF FocalPlaneResolutionUnit": "2", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard"}