Sessile-flowered species in the Navarretia leucocephala group (Polemoniaceae)

Navarretia myersii and N. prostrata of sect. Navarretia have a reduced habit, are nearly acaulescent, and have a terminal inflorescence. Mature floral heads bear sessile flowers and bracts on a common receptacle, surrounded by involucral leaves and bracts. This combination of features occurs also in a related, but new and rare plant described here as N. myersii subsp. deminuta. The three taxa are members of the N.leucocephala group, all of which are restricted to vernal pool habitats.