Marchantia polymorpha (L.)
The thallus, showing dichotomous branching, can be up to 2cm in width and 10cm in length. The thallus is thick and rigid and does not have a black midrib. The surface can be pale yellowish green when young and brown to purplish when old. The reticulate surface is easy to see as are the pores. The ventral scales are hyaline and inconspicuous. They are semilunar in shape and there are three rows on each side of the midrib. The gemma receptacles are cup-shaped. Male plants have stalked, flat-topped, disc-like receptacles with short rounded lobes. Female plants have receptacles with lobes that are finger-like and spreading.
Local: Alameda Gardens
Found growing on the soil of potted plants in the Alameda Gardens. Last seen there on March 2006.