Lanfrancia subglobosa was an early Eocene mastixioid plant that produced a small, rounded, multi-chambered fruit stone. The endocarp enclosed several seeds in curved cavities, with tough fibrous tissue forming the walls and partitions that protected them.

The surviving fruits preserve reproductive anatomy rather than the whole plant. Their internal structure is particularly useful because the partitions between the seed cavities are fibrous rather than broad and parenchymatous, helping separate Lanfrancia from the similar Exbeckettia. Apparent splitting into individual pyrenes in fossils may partly reflect pyrite decay rather than the behaviour of the living fruit.