Miconia guajaibonensis Judd, Bécquer & Majure

Description

Description Author and Date: Walter S. Judd, Eldis R. Bécquer Granados, James D. Skean Jr., and Lucas C. Majure modified from "Taxonomic studies in the Miconieae (Melastomataceae). XII. Revision of Miconia sect. Miconiastrum, with emphasis on the Miconia bicolor complex". Judd, Walter S., Bécquer Granados, Eldis R., Skean, James D., Jr., Majure, Lucas C.; J. Bot. Res. Inst. Texas. 8 (2): 457-491. 2014

Type: CUBA. Prov. Pinar del Río: Pan de Guajaibón, on the very top of the mountain, 750–800 m, 9 Jan 1921, fl, E. L. Ekman 12767 (LECTOTYPE: S!, designated by Walter S. Judd, Eldis R. Bécquer Granados, James D. Skean Jr., and Lucas C. Majure, 2014, because holotype at B destroyed; ISOLECTOTYPE: NY!, fragment).

Description: Evergreen shrub up to 4.5 m. Young stems terete to slightly quadrangular, the indumentum of dense, multicellular, ferrugineous, matted to erect, dendritic to globular stellate hairs or appressed stellate-peltate scales, becoming ± glabrate with age, without elongate, multicellular, non-glandular hairs, internodes 0.5–1.8 cm long, lacking longitudinal ridges, nodal line present, faint. Leaves isophyllous or nearly so; petiole 0.7–2.5 cm long, the indumentum of dense, ± matted, stellate-peltate scales to stellate-peltate scales, partially deciduous with age; the blade 3–8.6 (–9.3) × 0.7–2.4 (–3.3) cm, ovate, usually falcate, chartaceous, the apex acuminate to attenuate, the base obtuse to rounded, the margin plane to slightly revolute, entire; secondary veins two pairs, one pair conspicuous and one pair inconspicuous, acrodromous, basal, the innermost pair joining midvein at base to 1 mm above the leaf base, the conspicuous secondary veins placed 0.8–3.5 mm in from margin, the inconspicuous secondary veins intramarginal, tertiary veins percurrent, oriented subperpendicular to midvein, 0.7–4 mm apart, quaternary veins obscure to visible, ± reticulate, not connecting adjacent tertiary veins or with 1–3 quaternaries connecting adjacent tertiary veins, the higher order veins reticulate; the midvein and major secondary veins slightly impressed to flat, tertiary and higher order veins flat on adaxial surface, the midvein moderately to strongly raised, the major secondary veins flat to moderately raised, the minor secondary veins and tertiary veins flat, and the higher order veins flat on the abaxial surface; adaxial surface appearing smooth to slightly wrinkled after drying, with scattered to abundant druse crystals, and drying darker than the abaxial surface, the indumentum initially of dense, pale ferrugineous, stellate-peltate scales, but very quickly glabrescent, although a few scales often retained on midvein proximally; abaxial surface pale green but pale ferrugineous due to dense covering of stellate-scales, the epidermal surface ± smooth, with dense, appressed, ferrugineous or pale ferrugineous, stellate-peltate scales, 0.09–0.17 mm across, the veins with similar scales, but sometimes more irregular in form, such hairs on lamina and veins ± persistent; mite domatia present or absent, at junction of midvein and major secondary veins, consisting of dense cluster of multicellular, elongate, pale ferrugineous to red, barbate, eglandular hairs, 0.5–1 mm long. Inflorescences terminal, paniculate cymes, 3.5–9 cm long, 2.5–6.5 cm across, with 2–4 major branch pairs, the peduncle 1.7–3.8 cm long, the ultimate axes (pseudopedicels) 1–5.5 mm long, and numerous flowers well separated from each other; bracts 0.7–1 × 0.2–0.4 mm, but probably also larger, ± triangular or narrowly so, with acute to obtuse apex, early deciduous; bracteoles 0.4–0.7 × 0.1–0.2 mm, narrowly triangular, with acute apex, ± deciduous. Flowers 5-merous, zygomorphic (due to positioning of the stamens), with pedicel 1.3–3 mm long. Hypanthium 4.5–6 mm long, terete and ± slightly constricted above ovary, the free portion 1.8–3.3 mm long, 2.2–2.8 mm wide at the torus, the outer surface with moderate to dense, stellate-peltate scales, the internal surface smooth, glabrous. Calyx lobes 5, separate (and imbricate) in bud, the tube 1–1.7 mm long, irregularly tearing between lobes, with moderate to dense stellate-peltate scales abaxially, and moderate to dense stellate-peltate to globular stellate hairs adaxially, the lobes unequal, usually the 2 outer lobes larger than the rest, 0.45–1.2 × 1–2.4 mm, triangular to shortly triangular, the apex rounded to obtuse, with hairs similar to those of the tube, green, often red-tinged; calyx teeth present, ± 0.1 mm long, merely a dorsal, slightly ellipsoidal bump, with rounded apex, and hairs similar to those of calyx. Petals 5, 4.5–6.3 × 2.5–4 mm, obovate, spreading, white, glabrous but both surfaces densely papillose-granulate, the apex rounded and asymmetrically notched, the base slightly narrowed to a broad attachment, the margin entire. Stamens 10, isomorphic, ± geniculate near filament apex; staminal filament 4.5–5.5 mm long, glabrous, pale yellow, anther thecae 5–5.8 × 0.6–0.8 mm, subulate, straight to slightly incurved, opening by a small dorso-apical pore, yellow, the connective not prolonged below the thecae, glabrous, but the filament emerging from slight depression in sterile, minutely dorso-lobed anther base. Ovary 3-locular, ca. 4/5-inferior, 3.4–3.7 mm long, 1.4–2 in diameter, oblong to ellipsoid, apically conic, unridged, glabrous, the apex with a short, slightly ridged collar but lacking a crown, with axile placentation, the ovules numerous, borne on a small placenta not extending or only slightly extending into locule; style 10–13 mm long, distally curved, white, glabrous; stigma punctate, minutely papillose, 0.15–0.2 mm wide. Berries 5–8 mm long, 4.3–6.5 mm in diameter (excluding persistent hypanthium and calyx tube), globose to ellipsoid, purple-black, with sc

Phenology: Recorded in flower in January, March, May and November.

Distribution and ecology: Miconia guajaibonensis is endemic to Pan de Guajaibón, in Pinar del Río, Cuba (Fig. 5), from 680–800 m, in thickets over limestone.

Taxonomy and Systematics: Few collections of this rare and geographically restricted species are known, and Miconia guajaibonensis is morphologically quite uniform, although it seems to vary in the development of mite domatia, as in the western Cuban populations of Miconia bicolor. These two species likely are closely related, as both are characterized by an indumentum of stellate-peltate scales on the abaxial leaf surface; see key for their differentiating characteristics. The new name, Miconia quajaibonensis, is needed because the epithet “lanceolata” is occupied in Miconia, i.e., M. lanceolata DC. The new epithet highlights the only known locality at which this rare (and possibly endangered) species occurs. Currently, six species, including M. guajaibonensis, are known to be endemic to Pan de Guajaibón (Borhidi & Muñoz 1985; Borhidi 1991; Judd et al. 2008; Morejón & Sanchez 2012).