Lyonia alpina Urban & Ekman in Urban, Ark. Bot. 21A: 53. 1927.  Illustration:  Judd (1995), fig. 11.  Type.  Haiti.  Massif de la Selle, Morne de la Selle, in steep limestone side hills nr. the top (above Fonds Verettes), 2550-2650 m, 1 Feb 1925, Ekman H3162 (holotype, S;  isotypes, IJ, K, S).  Image:  Habit.
    Xolisma orbiculata Sleumer, Repert. Sp. Nov. 36: 272. 1934.  Lyonia orbiculata (Sleumer) Jiménez, Rhodora 62: 237. 1960.  Type.  Haiti.  Massif de la Selle, Gauthier, high limestone ridge nr. Morne Courty, ca. 2600 m, 20 Feb 1927, Ekman H7624 (holotype, S;  isotypes, IJ, LL n.v., S, US).
        Evergreen, low, spreading shrub to ca. 0.5 m tall, with gray, longitudinally furrowed bark; twigs slightly angled, slender to stout, moderately lepidote, otherwise glabrous or very sparsely pubescent; buds ovoid, 1-2 x 1-1.8 mm.  Leaf blades ovate to broadly elliptic to orbicular, 1.1-3.1 x 0.9-2.6 cm, ± flat, coriaceous, ca. 0.5-0.6 mm thick; base rounded to widely cuneate; apex truncate or rounded to nearly acute; margin plane to sometimes slightly revolute, apical portion obscurely and irregularly toothed, basal portion toothed to entire; venation brochidodromous, 3° veins ± reticulate; adaxial surface lepidote but scales usually quickly deciduous, sparsely pubescent on basal portion of midvein, veins obscure to sometimes faintly visible; abaxial surface moderately to densely lepidote, otherwise densely pubescent, with 2° and higher order veins usually obscure or nearly so (only very rarely raised and forming dense, fine reticulum); scales rust colored, persistent to deciduous, ca. 0.08-0.2 mm in diameter, usually ± erose; petiole 3-5 mm long, lepidote, otherwise adaxially pubescent; flower buds ± intermixed with vegetative buds.  Inflorescences fasciculate, ca. 5- to 8-flowered; pedicels clearly articulated with calyx, slender, 2-6 mm long, lepidote, otherwise glabrous or very sparsely pubescent; bracteoles ± opposite, basal, narrowly triangular, 1.5-2 mm long; floral bracts to ca. 2.5 mm long.  Flowers 4- or 5-merous; calyx lobes triangular, with acuminate apices, 1.5-2 x 0.7-1.4 mm, adaxial side pubescent, especially near apex, abaxial side lepidote, otherwise glabrous; corolla cylindrical, white, 5-6.5 x 3-4 mm, abaxially sparsely lepidote; filaments roughened, ca. 3.5 mm long, essentially unappendaged; anthers ca. 1.3 mm long; ovary lepidote, otherwise pubescent, placentae ± subapical.  Capsules ± globose to short-ovoid, 3-4 x 3-4 mm, slightly lepidote, otherwise sparsely pubescent, especially near base, the pale, very thick sutures separating as unit from adjacent valves; seeds 1.4-2 mm long.

        Distribution.  Endemic to Haiti (Massif de la Selle), on open, windswept forest of Pinus occidentalis on limestone ridges, at ca. 2500-2650 m elev.