Lathraea (toothwort) is a small genus of five to seven species of flowering plants, native to temperate Europe and Asia. They are parasitic plants on the roots of other plants, and are completely lacking chlorophyll. They are classified in the family Orobanchaceae.

Etymology

The genus name Lathraea derives from the ancient greek, meaning "clandestine", which is a reference to the fact that it is inconspicuous until it flowers.

Phylogeny

The phylogeny of the genera of Rhinantheae has been explored using molecular characters. Lathraea is the sister genus to Rhinanthus, and then to Rhynchocorys. These three genera share phylogenetic affinities with members of the core Rhinantheae: Bartsia, Euphrasia, Tozzia, Hedbergia, Bellardia, and Odontites. Melampyrum appears as a more distant relative.

Species

Cultural references

In Pavel Ivanovich Melnikov's "In the Forests" a Russian wise woman (znakharka) calls this plant Peter's Cross and says it protects against devils but only if collected with a prayer to God.