"Right now, I don't know what group these species of violet belong to, but there is a chance they belong to a group of very primitive violets," said Harvey Ballard, an assistant professor of environmental and plant biology at Ohio University. "It's likely their group predates the last Ice Age in Central America."
The violets were discovered some time ago growing in parts of Central America, and were classified as existing species. But upon closer inspection of the specimens, Ballard determined the two violets were new species.
"These species have been overlooked for years and had been misclassified," Ballard said. "But after I studied them for awhile, I knew they were new species."
Once that finding was recorded, Ballard had to name his discoveries, a familiar job for him. Ballard has discovered more than half a dozen plant species in his career, including several in the United States and five in Mexico and Guatemala.
"It's never an easy job to come up with meaningful names for new species because you want to be original," he said. One of the newly discovered plants was particularly difficult, he said, because it lacked a striking physical characteristic that could be linked to its name.
Ballard contrived the name Hybanthus hespericlivus for this nondescript violet -- Hybanthus the Latin name for the genus it presently belongs in and hespericlivus meaning "western slope."
"This violet tended to grow on the western slope in the area of Costa Rica where it was found, and that was the only distinguishing characteristic I could think of when trying to name it," he said.
Ranging in height from 3 to 15 feet, this violet has white petals that are three-quarters to an inch in length, and blooms throughout the year.
The other violet proved an easier plant to name, since its distinguishing feature is teeth-like edges on its leaves. Named Hybanthus denticulatus, this violet grows in the lowland rainforest from northern Nicaragua to eastern Panama. With purple and white petals a one-half inch in length, this violet stands between 3 and 6 feet tall and blooms year-round.
Ballard has begun molecular studies of the plants, which he hopes will allow him to identify their group. Both are shrubs, making their discovery even more rare. "Discoveries of flowering shrubs or trees don't happen often, which is another reason we're excited about this work," Ballard said.
The research, reported in a recent issue of the journal Novon, was co-authored by Mark Allen Wetter of the University of Wisconsin-Madison, and Nelson Zamora of the Instituto Nacional de Biodiversidad in Costa Rica.