PLANT: Annual (in AZ); stems solitary to much branched, erect to prostrate, leafy.
LEAVES: basal to alternate, simple to deeply pinnately lobed, the lobes confluent with the rachis, flat to terete, spinulose.
INFLORESCENCE: terminal, compact, bracteate, short woolly, the outer bracts deeply lobed.
FLOWERS: sessile, actinomorphic to slightly irregular; calyx tube membranes usually ruptured in fruit, the lobes subequal to strongly unequal, acute to attenuate, often spinulose; corolla actinomorphic, funnelform to salverform, or zygomorphic with at least 2 lobes unequal, white to deep bluish lavender; stamens equally to unequally inserted on the throat; anthers usually exserted; filaments equal to subequal in length; style included to exserted.
CAPSULE: ellipsoid to ovoid; seeds 1-several per locule.
NOTES: Ca. 14 spp.; sw U.S., nw MEX. (from the Greek erion, meaning wool, and aster, meaning star). Harrison, H. K., Brigham Young Sci. Bull. 16: 1-26. 1972.
REFERENCES: Dieter H. Wilken and J. Mark Porter, 2005, Vascular Plants of Arizona: Polemoniaceae. CANOTIA 1: 1-37.