Deuterocharacium consists of solitary cells that are attached to a substrate via a short mucilaginous pad or a pedicel. Cells are 30-50 μm long and 6-12 μm wide, cylindrical to ovoid, with a rounded or pointed tip. Cells have many small, discoid chloroplasts lining the inside of the cell membrane, which lack pyrenoids. Deuterocharacium has been described as uninucleate (i.e. containing a single nucleus);[1] other sources state the adult cells are multinucleate,[2] but this may be before the zoospores are formed. No eyespot is present.[1]
Deuterocharacium reproduces asexually; sexual reproduction has not been observed in this genus. It obligately produces zoospores which have two flagella and a single chloroplast containing a pyrenoid. Zoospores are produced in groups of 32 to 128, and are released through a tear in the mother cell wall.[1]
Similar genera include Characium and Pseudochlorothecium. Characium differs in having chloroplasts with pyrenoids. It differs from Pseudochlorothecium in that it does not reproduce via autospores, only via zoospores.[1]
Within Deuterocharacium, two species are known, D. polyplastidicum and D. fallax, which differ based on the shape of the cells.[2]
