Ledothamnus sessiliflorus N.E.Br.

  • Family

    Ericaceae (Magnoliophyta)

  • Scientific Name

    Ledothamnus sessiliflorus N.E.Br.

  • Primary Citation

    Trans. Linn. Soc. London, Bot. 6: 45. 1901

  • Type Specimens

    Specimen 1: Isotype -- J. J. Quelch 643, verif. J. L. Luteyn, 1988

  • Description

    Description: Wiry, rhizomatous shrublet to 3(-8) dm tall; mature stems often gnarled, terete to subterete, striate to ribbed, glabrous; bark cracking longitudinally; twigs subterete, glabrous or puberulent. Leaves in whorls of 3-4, strongly imbricate, ascending to strongly diverging from the stem, linear-oblong, ± trigonous in cross-section, 3-6 x 0.8-1.2 mm, base broadly cuneate and decurrent, apex acute, keeled (short-mucronate), apparent margins glabrous or ciliate and then also bearing short, translucent, eglandular, acicular hairs to 0.2 mm long, glabrate; petiole 0.5-1.2 mm long, glabrous or puberulent. Inflorescence terminal, flowers solitary; pedicel subterete, ca. 1.5-3 mm long, densely puberulent, also densely long-setose with translucent, eglandular hairs to 1.7 mm long; floral bract and bracteoles flat to concave above, ovate, 4-6 mm long, pubescent as leaves. Flowers 6-8-merous; calyx campanulate, (6-)7-11 mm long, puberulent, lobes spreading, ovate, 6.5-10 mm long, acuminate, similar in pubescence to leaves; petals wide-spreading (corolla rotate), oblong-elliptic, 11-18 x 5-7 mm, rounded to obtuse, scarlet when fresh, glabrous; stamens ca. 11 mm long; filaments 8-9 mm long; anthers 3-4 mm long; ovary glabrous; style (2-)3-4 mm long, glabrous. Capsule oblong, 4-5 mm long.

    Distribution: Endemic to the Venezuelan Guayana, where it is known only from Cerro Roraima and the adjacent tepuis, in exposed, rocky crevices, slopes of "morros," and around rocky pools of water, at 2450 to 2800 m elevation. Flowering and fruiting throughout the year. Rare.

    Type: Venezuela. Bolívar: Summit of Mount Roraima, 2620 m, Autumn 1898 (fl), Quelch & McConnell 643 (holotype, K; isotypes, BM, NY). The protologue cites the collection as McConnell & Quelch 643; however, the label on the type sheets reads the reverse.

    Illustrated: Maguire et al., Mem. New York Bot. Gard. 29:148, fig. 75A-G.

  • Floras and Monographs

    Ledothamnus sessiliflorus N.E.Br.: [Article] Maguire, Bassett. 1978. The botany of the Guayana Highland--part X. Mem. New York Bot. Gard. 29: 1-288.

    Ledothamnus sessiliflorus N.E.Br.: [Article] Luteyn, James L., et al. 1995. Ericaceae, Part II. The Superior-Ovaried Genera (Monotropoideae, Pyroloideae, Rhododendroideae, and Vaccinioideae P.P.). Fl. Neotrop. Monogr. 66: 560.