Psidium urquiolanum Landrum & Z.Acosta, 2023

Landrum, Leslie R. & Ramos, Zenia Acosta, 2023, A new species of Psidium (Myrtaceae) from Cuba, Phytotaxa 618 (2), pp. 195-201 : 196-200

Psidium urquiolanum Landrum & Z.Acosta sp. nov.

Type:— CUBA. Guantánamo: Baracoa, al sur de la loma del Yunque , (20.34°N, 74.57°W), 9 February 1972 (fl), Bisse 21450 (holotype: HAJB-G001291 !; isotypes HAJB-G001292 !, JE!) Figures 1–3 .

Diagnosis:—Similar to Psidium amplexicaule Persoon (1806: 27) but differs in having flower buds 5–7 mm long (versus 6–12 mm), style 3–5 mm long (versus 6–12 mm), stamens ca. 100 (versus 150–270), most leaves elliptic to obovate or oblanceolate (versus usually suborbicular), and petioles 2–4 mm long (versus 0–2 mm long).

Shrub or small tree up to 5 m tall, mainly glabrous but with minute hairs on some young growth and inner surface of calyx, the leaves and external surfaces of flowers densely glandular; hairs reddish brown, up to ca. 0.2 mm long; young twigs compressed to subterete, unwinged, glabrous to densely puberulent. LEAVES elliptic, oblong, obovate, or oblanceolate, (2.5–) 3–8.7 cm long, (1.5–) 2–4.2 cm wide, 1.3–2.3 times as long as wide; apex rounded to obtuse, sometimes emarginate; base rounded, cuneate, or broadly cuneate; petiole 2–4 mm long, 1.5–2 mm thick; venation brochidodromous, obscure to faintly visible, the midvein impressed or nearly flat above, prominent below, the lateral veins 4–6 pairs, leaving the midvein at an angle of 45–60 degrees, the marginal vein following the margin, arcing slightly between laterals, mainly running between 1 and 4 mm from margin, the tertiary veins rarely clear, dendritic, appearing to arise from the marginal vein; blades coriaceous, drying dark reddish-brown, densely glandular above and below, dull to slightly lustrous above and below, the margin revolute. FLOWER BUDS pyriform, 5–7 mm long, glabrous, densely and conspicuously glandular, the hypanthium ovoid to subcylindrical, 3–4 mm long, the distal portion of bud subglobose, 2–3 mm long; indumentum pattern of buds with all external surfaces glabrous, the inner surface of calyx and staminal ring minutely puberulent, the hairs mainly appressed; peduncles 1-flowered, (2–) 4–20 mm long, 0.8–1 mm wide, flattened or subterete, borne in the axils of leaves, or small bracts, often grouped together in short bracteate shoots, these usually at the tips of branches, but sometimes at the base of a young leafy shoot, the buds often of various sizes and stages of maturity in a single inflorescence, the bracts ovate to triangular, ca. 1–1.5 mm long; bracteoles narrowly triangular, ca. 1 mm long. CALYX closed in bud, with a terminal pore through which minute reddish brown hairs emerge, usually tearing in 4 nearly equal, subtriangular lobes, these 3–5 mm long, ca. 3 mm wide, the tears between lobes not cutting deeply into the staminal ring; petals 5, suborbicular, not persisting; disk 3–4 mm across, the staminal ring densely puberulent, 1–2 mm wide, the disk within staminal ring sparsely pubescent to glabrous; stamens ca. 100; anthers ca. 0.5 mm long, with a terminal gland and a few smaller glands below; style 3–5 mm long, glabrous, glandular; ovary 2–4-locular; ovules 16–20 per locule, mainly uniseriate, the placenta peltate. FRUIT globose, ca. 1 cm wide; seeds ca. 7, lenticular to reniform, somewhat flattened, ca. 4 mm long, the seed coat several cells thick at narrowest point, the embryo ca. 2 mm long in curved state.

Etymology:—The epithet honors Dr. Armando Jesús Urquiola Cruz (1949–2009), eminent Cuban botanist, founder of the Botanical Garden of Pinar de Río, who dedicated his life to the study and conservation of the flora of Pinar de Río, the family Myrtaceae , and Cuban aquatic plants.

Paratypes:— CUBA. Guantánamo: Baracoa, alto entre Loma del Mirador y Loma de Buena Vista (al oeste de Camarones ), (20.44°N, 74.60°W), 500 m, 6 August 1975 (fl), Álvarez et al. 27136a ( HAJB!, JE!), (fr), Álvarez. et al. 27137 (HAJB!, JE!); cabezada del Río Naranjo , (20.44°N, 74.69°W), 27 February 1975, Álvarez et al. 27136b ( HAJB!); Baracoa, camino de Los Naranjos a la Loma de Buenavista , (20.45°N, 74.65°W), 200 m, 21 January 1977 (fl), Álvarez et al. 33784 ( HAJB!, JE!); camino a vega de la Palma, orillas de Arroyo Blanco , (20.33°N, 74.63°W), 27 February 1979, Areces et al. 40095 ( HAJB); Baracoa, valle al noroeste del Yunque de Baracoa , (20.34°N, 74.55°W), 31 January 1968 (bud), Bisse & Kohler 5291 ( JE!); Baracoa, altiplano de la Mina Iberia , (20.46°N, 74.73°W), 600 m, 29 February 1968 (fr), Bisse 6818 ( JE!); Baracoa, valle del Río Maraví , (20.42°N, 74.58°W), 31 March 1970 (st), Bisse 16967 ( HAJB!, JE!); Baracoa, al sur de la Loma del Yunque , (20.34°N, 74.55°W), 300 m, 31 March 1970 (ofl), Bisse 17073 ( JE!); Baracoa, orillas del Río Báez , cerca del campamento` Los Naranjos` , (20.45°N, 74.58°W), 1 August 1975 (fl), Bisse 27000 ( HAJB!, JE!). Holguín: Moa, Cuchillas de Moa , alrededores del aserrío La Melba , (20.45°N, 74.82°W), 28 April 1980 (fl), Álvarez et al. 42244 ( HAJB!, JE!); Moa, orillas del Río Jiguani , cerca del segundo aserrio de La Melba , (20.45°N, 74.82°W), 31 March 1968 (bud), Bisse & Kohler, E. 6774 ( HAJB!, JE!); Moa, La Melba , (20.45°N, 74.82°W), 27 December 1968 (bud, fl), Bisse & Lippold 11888 ( HAJB!, JE!); charrascal de Cayo Guam, Moa, al W del campismo, (20.58°N, 74.86°W), 30 June 1991 (yfr), Urquiola 7108 ( ASU0060189 !).

Distribution, habitat, and conservation status:— Psidium urquiolanum is only known from eastern Cuba, and its habitat is described on specimen labels as charrasco, charrascal, pluviosilva, or monte nublado at elevations of 200 to 700 m. Charrascal vegetation is associated with serpentine soils, so we suspect that this species is one of the several endemic plants of such soils in eastern Cuba ( Borhidi 1996). Psidium urquiolanum has been collected several times and does not seem to be of urgent conservation concern, but we recommend that field studies be conducted to assess its conservation status.

Figures

FIGURE 1. A. Closed flower bud from side and above, showing apical pore in closed calyx with small hairs protruding; young leafy shoot with flower buds at first two nodes. B. Two older shoots with one closed bud and flowers at first two nodes. C. Flower after anthesis, with enlarged calyx remnant showing external glandular surface. D. Twig and leaf, with enlarged part of margin and twig; venation more evident than usual. E. Developing fruit on branchlet with leaves attached; closer view of young fruit. F. flattened mature fruit, with seeds emerging. G. Cross section of ovary showing 4 locules with peltate placentas with ovules; one placenta extracted with ovules. H. Seed in section showing C-shaped inner cavity with embryo in place. I. Extracted embryo with reflexed cotyledons.

FIGURE 2. Maps of distribution of Psidium urquiolanum: above, showing all of Cuba; below showing only eastern Cuba.

FIGURE 3. Image of holotype specimen at HAJB.