Penstemon pseudoparvus

Penstemon pseudoparvus seems most closely related to P. oliganthus. Though no intergradation is evident between these two species, their morphologic and geographic nature suggests a recent common ancestor. The most striking distinguishing characters are habit, corolla shape, and corolla orientation. P. pseudoparvus is the shorter plant, taking its name form the similarity in the habit with P. parvus Pennell of the Aquarius Plateau of Utah. The straight corollas of P. pseudoparvus are quite similar to those of P. parvus, being considerably straighter than those of P. oliganthus. The internal morphology of the flower, however, indicates that P. pseudoparvus has no connection with P. parvus. The ascending orientation of the flowers of P. pseudoparvus is sharply different from the drooping or horizontal orientation of those of P. oliganthus. The corollas of P. parvus are also ascending. Pollinator adaptations are probably involved and should be studied.