Kingdom: Eubacteria
Phylum: Cyanobacteria
Order: Oscillatoriales

British distribution: Evidently widespread.
World distribution: Widespread.

Species of Oscillatoria occur in a diverse range of conditions, in damp soil or on dripping rocks, in freshwater, in the sea and in hot springs. Some are tolerant of high levels of organic pollution and some are shade-tolerant and able to survive in water below blooms of green algae. In water they may be benthic or planktonic. O. rubescens is a red species that can form conspicuous red blooms in eutrophicated lakes.
Oscillatoria is implicated in irritation of skin and mucous membranes suffered by people swimming off tropical coastlines.

Original photograph at × 500 magnification, from material ex culture.

Reference:
Van den Hoek, C., Mann, D.G., & Jahns, M.M. (1995). Algae: an introduction to phycology, Cambridge University Press.