Flora of North America species comparison

Reports of Gentiana parryi outside the range indicated here have been based on specimens of G. calycosa or G. affinis (studies for this flora). Because of its restriction to high altitudes, populations of G. parryi are widely scattered, especially in the southern part of its range.

Gentiana parryi has sometimes been included in G. calycosa and less often in G. affinis, but its larger, conduplicate involucral leaves, which are more or less sharply differentiated from the distal cauline leaves and largely envelop the calyces, give G. parryi an aspect distinctly different from that of either G. calycosa or G. affinis. Biometric studies by J. R. Spence (unpubl.) have supported its recognition as a species. As noted by N. H. Holmgren (1984b), these species also differ in anther length, which is 3.5–5 mm in G. parryi and 1.6–3.2 mm in G. calycosa and G. affinis. In the Rocky Mountains of central Colorado, G. parryi and G. affinis appear especially well differentiated. Where the ranges of G. parryi and G. calycosa approach each other in the Intermountain Region, G. parryi usually grows in drier habitats than G. calycosa. The distinctive involucre of G. parryi is less well developed in some Arizona plants otherwise identifiable as this species, which should be given further study.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

The name Gentiana alba Muhlenberg has often been applied to this species. Uncertainty had long persisted, first as to whether the name G. alba was validly published by G. H. E. Muhlenberg in 1813, then, after that publication had been deemed invalid, whether it was validated by T. Nuttall in 1818. A group of nomenclatural authorities considered this issue on behalf of this flora and concluded that neither of those publications of the name G. alba had been valid, and that G. flavida A. Gray was the earliest validly published name for this species (K. N. Gandhi, pers. comm.).

Outlying eastern populations of Gentiana flavida in North Carolina, Pennsylvania, and West Virginia are no longer extant, and the continued existence of other peripheral populations in isolated prairie remnants is precarious. Reports from Manitoba have been based on misidentified G. rubricaulis. A report from Maryland was based on the misreading of a label of a specimen actually from Indiana (studies for this flora).

In contrast to those of the other species of Gentiana in the flora area, with the exceptions of G. clausa and G. latidens, the calyx lobes of G. flavida spread widely, with keels like shelf brackets decurrent on the tube.

Morphological variation in Gentiana flavida should be given further study. According to J. T. Curtis (1959), plants of this species from the northern part of its range, as seen in the field, appear distinctly different in inflorescence form from plants native farther south.

In the tall-grass prairies, Gentiana flavida hybridizes with G. andrewsii, producing G. × pallidocyanea J. S. Pringle, and G. puberulenta, producing G. × curtisii J. S. Pringle. Reports of G. flavida with the corollas distally lilac have been based on plants derived from such hybridization, probably through backcrossing.

(Discussion copyrighted by Flora of North America; reprinted with permission.)