roman_romanov's Identifications

A visible colony about 20cm in diameter of Nostoc commune was observed outside growing on bare soil in a field at NKU by the Science Building. It is a gelatinous mass with many filaments enclosed. Nostoc commune is a cyanobacteria with the common name of star jelly, witches butter, or mares eggs. It is in the family Nostocaceae. It has a slimey, gelatinous blue-green look. The filamentous photosynthetic cyanobacteria that can survive extensive periods of dry weather, and return when moisture reappears . When viewed under the microscope, the cyanobacteria is filamentous, and will have heterocysts which are nitrogen fixing spheres scattered in its chain. It seemed to not be an abundant organism, because only a couple patches in a large field were seen. It is possible that there could’ve been more just camouflaged in with the grass. Nostoc reproduces asexually through spore formation or heterocysts. Although a large colony is visible, it can be a colony so small that it’s not visible to the naked eye. The individual cyanobacteria can be viewed under a microscope.

Part of a mixed community of cyanobacteria and lichens that have colonized a sock, embedded in the mud of a flooded abandoned quarry. The filaments of Scytonema are embedded in thick yellow sheaths, 12 to 20 microns wide. The epifluorescence photos reveal the form of the filaments within the sheaths.