Folk, R. A., & Freudenstein, J. V. (2015). “Sky islands” in the eastern U.S.A.? — Strong phylogenetic structure in the Heuchera parviflora group (Saxifragaceae). Taxon, 64(2), 254–271. doi:10.12705/642.3
Species |
Distribution |
Leaves |
Flowers |
Habitat |
Heuchera puberula |
Ozark Plateau (Missouri and Arkansas) |
Leathery, with short-hairy petioles (less than 0.5 mm) |
Bracts mostly entire |
Calciphile (dolomite/limestone), more exposed areas, riparian |
Heuchera missouriensis |
Interior Plateau and southern Cumberland (southern Illinois, southern Indiana, extreme eastern Missouri, western Kentucky, parts of Tennessee, northern Alabama) |
Membranous, thin, petioles long-hairy (usually >0.6 mm) |
Bracts mostly trifid, styles exserted <1.25 mm, inflorescence notably condensed, with lower pedicels mostly <5 mm, flower orientation subhorizontal |
Rockhouses, only occasionally riparian |
Heuchera parviflora var. parviflora
|
Northern Cumberland, disjunct in the southern Appalachian Escarpment (southern Ohio, eastern Kentucky, parts of Tennessee, western North Carolina, parts of western South Carolina and northern Georgia?) |
Membranous, thin, petioles long-hairy (usually >0.6 mm) |
Styles exserted <1.75 mm, inflorescence open, lower pedicals mostly >5 mm, flowers pendant |
Exclusive to sandstone |
Heuchera parviflora var. saurensis
|
Endemic to North Carolina in Piedmont, mostly in Sauratown Mts, also foothills of Appalachians |
Mature leaves strongly sticky-viscid, membranous, thin, petioles long-hairy (usually >0.6 mm) |
Styles exserted <1.75 mm, inflorescence open, lower pedicals mostly >5 mm, flowers pendant |
Exclusive to quartzite |
Why should this change be applied to species in the western United States and Europe?