XVI International Botanical Congess

Fossombronia texana has been an enigma since it was named by Lindberg (1875). The type material was collected in Texas and issued with plants collected in California under the name F. longiseta by Austin (1869). The distinction between these two taxa was evident upon obtaining the Texas material (H-SOL) and comparing it with the California plants in the Austin herbarium (MANCH). Past authors have suggested that F. mexicana and F. cubana are conspecific with F. texana. Light and SEM microscopy of gametophyte and sporophyte characters show this is not the case. Study of natural populations in Texas shows further that F. texana is restricted to areas of high calcium. Due to high soil moisture levels most of the year, the plants are perennial.