The genera and species of this family are usually semiparasites feeding on other plants.

T. pyrenaicum or meadowflax is a perennial herb between 15 and 50 cm.high.

With standing stem(s) the leaves are lineal, with three veins, alternate, without stipules.

The flowers, with 3-5 petals, are tube-shaped, and bloom in June and July.

The petal tops roll in during the fruiting season.