Ultraviolet light gives desmid alga cell a bright red glow

Illuminated with ultraviolet light, this living desmid cell has a bright red chloroplast. USGS biologist Barry H. Rosen, an expert on aquatic microorganisms, takes exquisite microscopic photos as part of his study of these single-celled green algae, which he has collected in a nearly pristine area of the northern Everglades. This cell got smooshed (the technical term for it) “as I fussed to get the perfect image of this living holiday ornament,” Rosen says. 

Microsterias radiosa species collected in Loxahatchee National Wildlife Refuge, February 2017 Photo: Barry Rosen, USGS