A NEW SPECIES OF PHLOX (POLEMONIACEAE) FROM NORTHERN MEXICO WITH AN EXPANDED CIRCUMSCRIPTION OF SUBSECTION DIVARICATAE

Phlox pattersonii, a new species from the northern Sierra Madre of Coa huila and Nuevo Leon, Mexico is described. It is morphologically simil ar to P. pilosa var. ozarkana of the east-central United States, but d iffers in its suffruticose habit, alternate upper leaves, many nodes, and summer blooming period. None of the subsections of Phlox can accom modate the new species as currently circumscribed, though it is clearl y allied to subsections Divaricatae and Drummondianae. A new circumscr iption of subsect. Divaricatae is proposed which includes subsect. Dru mmondianae and P. pattersonii.