Abstract Detail

Systematics

Zumwalde, Bethany A [1], Ballard Jr, Harvey E [2].

A new endemic species of Viola (Violaceae) from the Mid-Appalachian shale barrens.

Within the genus Viola (Violaceae) is a well-known temperate and tropical montane group, subsection Boreali-Americanae in Section Plagiostigma. The group, informally known as the acaulescent blue violets, is endemic to North America and contains 10-25 species, depending on the taxonomic treatment. A small complex of violets in the subsection with all leaf blades lobed or dissected leaves has been familiarly recognized to include three main taxa. All specialists have accepted Viola pedatifida G. Don. of Midwestern and Great Plains prairies as a distinct species. Viola brittoniana Pollard of marshes and stream-sides near the Atlantic Coastal Plain, has been treated as both a distinct species or as a subspecies of V. pedatifida due to morphological similarities of the two taxa. A third taxon has been recognized by violet specialists as a highly polymorphic species or a series of hybrid populations, ranging through the eastern Great Lakes and Appalachian Mountain regions. This latter has been called Viola subsinuata (Greene) Greene or Viola palmata L. Disjunct populations of Viola pedatifida were first reported in 1951 from the mid-Appalachian shale barrens region of Allegheny and Bath Counties in Virginia but have been universally disregarded until recently. We began investigations of the disjunct Virginia populations in 2012 and quickly accumulated compelling evidence that they represent an indigenous, previously undescribed narrow endemic wholly confined to a small area of unusual shale woodland slopes. Morphological studies included phenetic analyses of leaf, flower, cleistogamous capsule and seed variables, in addition to micromorphological comparisons using scanning electron microscopy of seed coats and lateral petal trichomes. Preliminary ecological studies analyzed microhabitat variables, and genetic studies utilized four microsatellite loci. These studies confirmed extensive differentiation at all levels among V. pedatifida, V. brittoniana, Viola subsinuata and the shale woodland violet. All evidence supports the recognition of the Virginia violet as a new, narrowly endemic species, Viola tenuisecta Zumwalde & H. E. Ballard.

1 - Desert Botanical Garden, 1201 N Galvin Pkwy, Phoenix, AZ, 85008, United States
2 - Ohio University, Department of Environmental and Plant Biology, 315 Porter Hall, Ohio University, Athens, OH, 45701, USA

Keywords:
Violaceae
microsatellites
micromorphology
Phenetic
Viola.

Presentation Type: Oral Paper
Session: 41, Basal Rosids & Rosids I
Location: 101/Savannah International Trade and Convention Center
Date: Wednesday, August 3rd, 2016
Time: 10:30 AM
Number: 41010
Abstract ID:389
Candidate for Awards:None