Nothochelone
Brittonia 18: 85. 1966.
Herbs, perennial; caude× unbranched, woody. Stems arching or reclining, glabrous or puberulent. Leaves cauline, opposite; petiole absent or present; blade not fleshy, not leathery, margins subentire to serrate or dentate. Inflorescences axillary or terminal, cymes; bracts present. Pedicels present; bracteoles smaller than calyx lobes, not surrounding calyx of flower they subtend. Flowers bisexual; sepals 5, connate proximally, distinct nearly to base, calyx radially symmetric, campanulate, lobes ovate to lanceolate; corolla pink, pinkish to bluish purple or maroon-red, often paler abaxially, bilaterally symmetric, bilabiate, tubular, tube base not spurred or gibbous, throat not densely pilose internally, lobes 5, abaxial 3, adaxial 2; stamens 4, adnate to corolla, didynamous, filaments hirsute proximally, puberulent distally; staminode 1, straplike; nectary a hypogynous disc; ovary 2-locular, placentation axile; stigma capitate. Fruits capsules, dehiscence septicidal. Seeds ca. 50, tan to brown, flattened, wings present. x = 15.
Distribution
w North America.
Discussion
Species 1.
Nothochelone is a member of Cheloneae, which in North America includes Chelone, Chionophila, Collinsia, Keckiella, Penstemon, and Tonella. These genera share cymose inflorescences, presence of a staminode, simple hairs, and stems that contain pith (A. D. Wolfe et al. 2002). In phylogenetic analyses using molecular (Wolfe et al.) and morphological (A. D. Nelson 1995) data, N. nemorosa occurs in a clade with species of Chelone. Nothochelone has a more branched cyme with relatively small bracteoles, abaxially ridged corollas, circular pollen amb (grain shape from polar view), reticulate pollen exine sculpting, and asymmetric seed wings; Chelone has smaller cymes with relatively large bracteoles, adaxially ridged corollas, triangular pollen amb, rugulate-reticulate pollen exine sculpting, and circumalate seeds (Nelson). Both genera have hypogynous disc nectaries (Wolfe et al.). Chionophila shares a clade with sister genera Chelone and Nothochelone. Chionophila has spikelike racemes without bracteoles, no ridges on the corolla, circular pollen amb, reticulate pollen sculpting, seeds with wings, and epistaminal nectaries.
Selected References
None.