Ruellia

Both of our species have few but rather showy pink-violet to blue-violet flowers in nearly sessile or short-stalked terminal or axillary clusters.

1. Calyx lobes narrowly linear, up to 1 mm broad at base and ca. 15–30 times as long; leaves with spreading hairs (much longer than any minute strigose ones), especially on main veins and margins.

R. humilis

1. Calyx lobes lanceolate, ca. 3–6 times as long as broad; leaves with minute usually ± strigose pubescence.

R. strepens

All species found in Ruellia

Ruellia humilisHAIRY RUELLIA 
Ruellia strepensSMOOTH RUELLIA 

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. May 30, 2017. http://michiganflora.net/genus.aspx?id=Ruellia.