4. Triantha (Nuttall), Gen. N. Amer. Pl. 1: 236. 1818.
[Greek tris, three-, and anthos, flower, alluding to aggregation of flowers in threes upon spikes]
John G. Packer
Tofieldia Hudson sect. Triantha Nuttall, Gen. N. Amer. Pl. 1: 236. 1818
Herbs, perennial, rhizomatous. Stems glandular and/or glandular-pubescent. Leaves mostly basal with 0–3 towards stem base, 2-ranked, equitant; blade linear. Inflorescences terminal, racemose, open or dense and spikelike, elongating in fruit, bracteate, bracteolate; bracteoles connate in epicalyx. Flowers borne in clusters of 2–7; tepals persistent, 6, in 2 somewhat dissimiliar series, distinct; stamens 6; filaments strongly flattened, dilated basally; anthers basifixed, 2-locular, introrse, without appendages; ovary superior, stipitate, apocarpous basally, glabrous; intercarpellary nectary present; styles 3. Fruits capsular, ovoid to broadly ellipsoid or cylindrical, glabrous, dehiscence septicidal, then adaxially loculicidal. Seeds appendaged. x = 15.
Species 4 (3 in the flora): North America, Japan.
Recognition here of the genus Triantha follows J. G. Baker (1879) and R. R. Gates (1918); see J. G. Packer (1993). R. W. Cruden (1991) provided cladistic evidence supporting this segregation from Tofieldia.
In the absence of any clear understanding of evolutionary relationships within Triantha, the species are here listed alphabetically.
Hitchcock, C. L. 1944. The Tofieldia glutinosa complex of western North America. Amer. Midl. Naturalist 31: 487–498. Packer, J. G. 1993. Two new combinations in Triantha (Liliaceae). Novon 3: 278–279.