Symplocos retusa Kriebel, González & Alfaro (2004: 56)

Kelly, Lawrence M., Almeda, Frank & Fritsch, Peter W., 2016, A taxonomic revision of Mexican and Central American Symplocos (Symplocaceae), Phytotaxa 264 (1), pp. 448-450 : 448-450

24. Symplocos retusa Kriebel, González & Alfaro (2004: 56) . Type :— COSTA RICA. Pérez Zeledón : Parque Nacional Chirripó , Cordillera de Talamanca, sendero al Cerro Urán, 2640 m, 09°31′41″N, 83°35′17″W, 6 April 1995, J. A. González 638 (holotype INB!, isotypes CR!, F!, MO!)

Trees 8–12 m tall; juvenile branchlets and vegetative buds glabrous. Petioles 5–14 mm long; leaf blades typically concolorous, yellowish green, rarely slightly bicolorous, brownish green adaxially and yellowish green abaxially, elliptic, 4.3–8.5 × 1.6–2.9 cm, subcoriaceous, glabrous, secondary veins not adaxially impressed, base acute, margins entire, apex retuse. Inflorescences 1-flowered or rarely 2- or 3-flowered; peduncles 8–15 mm long, glabrous; bracts caducous, 1 or 2 toward base of peduncle, ovate to deltoid, 1.5–2 × 1–2 mm, glabrous, margins ciliate; bracteoles caducous, 1 or 2, ovate to deltoid, 1.5–2 × 1–2 mm, glabrous, margins ciliate. Hypanthium glabrous. Calyx lobes 5, ovate, 2–3 × 1–2 mm, glabrous, margins ciliate. Corolla pale violet, 5-lobed, 6–8 mm long; tube connate for 3–4 mm; lobes adnate to filament tube for 3–5 mm, narrowly to broadly oblanceolate, glabrous. Stamens 3–4-seriate; filament tube 2–3 mm long; distinct portions of filaments 2–3 × 0.25–0.6 mm. Disk persistently pilose; style ca. 6.5 mm long, glabrous; stigma irregularly lobed. Fruits green maturing to dark bluish purple, ellipsoid, 6–10 × 3.5–5 mm, glabrous, apex gradually narrowed to the truncate disk; calyx lobes erect; disk pulvinate, surpassing calyx lobes and well exposed; endocarp 3–4-locular, perimeter rounded.

Vernacular name —None.

Illustration —Kriebel et al. (2004: 58).

Phenology —Flowering February, April, July, and December; fruiting May and July.

Distribution and habitat — Costa Rica (Pacific slope of the Talamancas) and western Panama, uncommon in moist forests at 1250–3000 m elev. Figure 30 .

Conservation status — Symplocos retusa is restricted to the Cordillera de Talamanca of Costa Rica and westernmost Panama. The species is known from 13 collections representing about nine populations. Only four of these are afforded some protection, one in Costa Rica’s Chirripó National Park and three in Panama’s portion of La Amistad International Park and the contiguous Reserva Forestal de Fortuna. The EOO is 2395 km ² and the AOO is 36 km ². Based on these data, the restricted AOO, and a projected decline in area, extent, and quality of habitat due to deforestation threats, we assign a classification of Endangered (EN): B2ab(ii) to this species.

Discussion — Symplocos retusa is easily distinguished by the combination of its glabrous, entire-margined leaves with a retuse apex, solitary purple flowers, and fruit with a conspicuous pulviniform disk that protrudes beyond the persistent sepals.

A TAXONOMIC REVISION OF SYMPLOCOS

Phytotaxa 264 (1) © 2016 Magnolia Press • 79

Additional specimens examined — COSTA RICA. Cartago: along Interamerican Hwy ca. 4.5 km E of Hwy 222, 2150–2200 m, 09°44′N, 83°57′W, 30 July 1979, Stevens 13457 (C!, CAS!, F!, MO!) ; area near El Canon, 40 km S of Cartago, Cordillera de Talamanca , 2500 m, [9°40′59″N, 83°55′01″W], 26 January 1965, Williams et al. 28218 (NY!, US!) . Puntarenas: Coto Brus, Zona Protectora Las Tablas, Estación Las Alturas de Cotón , 1800 m, 08°58′20″N, 82°50′05″W, 20 May 2000, Alfaro 3184 (CR!, INB!, MO!) ; Zona Protectora Las Tablas, trail from Biol. Station above Finca Las Alturas to Cerro Echandi , 2180 m, [8°57′N, 82°44′W], 19 February 1991, Almeda et al. 6731 (CAS!, CR!, INB!, MO!, NY!) . San José: Cordillera de Talamanca, Pacific slope of the Chirripó massif, 2700–3000 m, [9°28′47″N, 83°31′45″W], 6 April 1969, Davidse & Pohl 1642 (MO!, US!) ; San Gerardo de Dota , 2250 m, 09°34′31″N, 83°48′20″W, 30 July 1996, Wasselingh et al. 25 ( CR!) , Wasselingh 27 ( CR!) .

PANAMA. Chiriquí: in and along wooded slopes on Cerro Horqueta , 1650 m, [08°49′N, 82°27′W], 13 August 1974, Croat 26946 (MO) ; sendero Río Hornito , 08.68334°N, 82.22239°W (08°41′N, 82°13′20.6″W), 21 September 2011, Kriebel & Burke 5753 (CAS!, NY!) ; vicinity of Fortuna Dam , forested slopes along ridge at southern boundary of watershed, 1250 m, 08°45′N, 82°15′W, 28 April 1986, McPherson 9111 (MEXU!, MO!) ; near Fortuna Dam, on slopes of Cerro Hornito above Los Planes , 1300 m, 08°45′N, 82°15′N, 7 December 1987, McPherson 11843 (MEXU!, MO!) ; Cerro Hornito , 40 km NW of Gualaca, 2238 m, [08°39′N, 82°11′W], 26 July 1975, Mori & Bolten 7492 (CAS!, MO!) .

Figures

FIGURE 30. Geographic distribution of Symplocos retusa and S. striata.