This little flower could develop a 'complex'

You sometimes hear of a person, or people, developing a "complex," which is usually not such a good thing. Maybe plants develop complexes, too.

This little plant could develop a complex. It's very tiny, humbled below its various taller and flashier relatives. Its leaves are puny and bractlike, and its flowers, while pretty, are small enough that unless you are a visiting insect, you basically have to get on your hands and knees to see them. Yes, this plant sure enough has developed a complex — what we call a "species" complex.

Botanists refer to a species complex as a group of closely related species that are difficult to distinguish as individual units, and which probably all hybridize with each other if growing together, often resulting in complicated but very interesting genetics. Because the members of a species complex are often hard to precisely evaluate, their naming also ends up being something of a problem — sometimes a big problem. Usually, the identified members of a species complex have had more than one scientific name applied to them, which, of course, is a botanical no-no.

This little herb doesn't get much taller than about a foot off the ground, often hidden among the grasses nearby. It's related to foxgloves and the garden digitalis. Like them, its flowers exhibit a lot of "fusion": The five sepals are fused, forming a tubular calyx, and the five petals are fused into a tubular corolla. The corolla is bright pink and softly hairy on the inside, protecting four tiny stamens and a pistil.

The leaves are quite narrow, more like scales than regular leaves. The stems are smooth and a bit yellowish.

Our Mystery Plant blooms in the fall, and usually only one or two flowers will be open at a time on a single plant. The corolla lasts only one day, then falls off. Except for the flowers, which individually are attractive, the whole plant is rather inconspicuous. This particular species, weakly defined as it is, occurs in a variety of habitats from New Jersey through Tennessee down to Louisiana, and well into central Florida.

The species complex in which this plant resides is the source of serious research by my colleague Dr. Maile Neel and her student, Jamie Pettengill, both of whom are botanists from the University of Maryland. Recently they were here in South Carolina studying this plant where it occurs in Lee County, at Lynchburg Savanna Heritage Preserve, a protected site being maintained by the S.C. Department of Natural Resources.

The research they're performing is rather intensive, involving carefully measuring the stems, leaves, bracts, flower stalks and corollas of at least 30 plants in a given population. Their research is also being backed up by molecular studies of the DNA sequences in the leaf tissue. It's a lot of work, but hopefully they will be able to further explain the accurate relationships between this little plant and its nearest relatives.

This week's Mystery Plant: Agalinis obtusifolia, "autumn bells," "little finger-pink."

John Nelson is the curator of the herbarium in the department of biological sciences at the University of South Carolina in Columbia. The herbarium offers free plant identifications. Visit www.herbarium.org or call 803-777-8196. For more information on Lynchburg Savanna or other He