Family - Lamiaceae

Stems - To +20cm tall, multiple from base, simple, from fibrous roots, 4-angled, 1-3mm thick, densely glandular and simple pubescent to glabrous or sparse pubescent, herbaceous, erect.

Leaves - Opposite, sessile, entire, ovate, to +/-1.5cm long, +/-8mm broad, densely glandular pubescent or sparsely pubescent. Margins sometimes revolute.

Inflorescence - Paired axillary flowers. Pedicels 2-3mm long, hirsute.

Flowers - Corolla tubular, bilabiate, to 1cm long, externally pubescent. Lower lip +3mm broad, mottled with violet and white, larger than upper lip. Upper lip galeate. Stamens 4, didynamous, included within upper lip. Filaments to 3.5mm long, white, glabrous. Ovary 4-lobed. Calyx 2-lobed, with dorsal protuberance on upper lobe, densely glandular pubescent, 3.5mm long, accrescent.

Flowers close-up.

Calyx.

Flowering - April - July.

Habitat - Glades, open woods, prairies, bluffs.

Origin - Native to U.S.

Other info. - This is a tiny plant which can be easily overlooked. The plant produces a "moniliform" rhizome, which means "constricted at regular intervals" (like a pearl necklace, for example). It sort of resembles roots infected with nematodes.
The plant can be found in rocky open areas of the habitats mentioned above.
Steyermark lists three varieties for the plant based on leaf, stem, and calyx pubescence and leaf morphology. I won't go into those here.
In the same habitat as this plant you can usually find many a Centruroides scorpion:

Fortunately, I like scorpions. I used to breed a few different species and donated part of my collection to a fellow named Kari McWest, so he could finish his graduate research. Kari - drop me a line.

Photographs taken on Coy Bald, Mark Twain National Forest, Taney County, Mo., 4-28-00, and off Hwy 106, Shannon County, MO., 5-23-03.