Matricaria L.
Annual herbs. Lvs 2-3-pinnatisect, alternate. Capitula in corymbs or often solitary, terminal, pedunculate; involucral bracts in 2-3 rows, with membranous margins. Receptacle conic; scales 0. Outer florets ♀ and ligulate, or ⚥ and tubular; ligules white; inner florets ⚥, tubular. Achenes usually all similar, terete, mucilaginous when wet; ribs 3-10, strongly developed on inner surface; pappus a small corona or 0.
Key
6 spp., Europe, Asia, N. America. Naturalised spp. 2.
Matricaria sens. strict., as defined here, includes only a small group of annuals which are part of the Anthemis assemblage. Some treatments refer these spp. to Chamomilla S. F. Gray, and others include many more spp. under a broader circumscription of Matricaria.