Gesneria pulverulenta Alain

Gesneria pulverulenta Alain

Gesneria pulverulenta Alain, Mem. New York Bot. Gard. 21(2):146, 9 June 1971.

Gesneria filisepala Alain, Phytologia 22:173, 2 December 1971. [Type-collection: Hoyo de Pelempito, Dominican Republic, Alain Liogier 18132 (NY, holotype; GH, US, isotypes).]

Gesneria saxatilis Alain, Phytologia 22:173, 2 December 1971. [Type-collection: Trail between Pedernales and Aceitial, R. Howard & E. Howard 8120 (NY, holotype; BM, GH, P, S, US, isotypes).]

Subshrubs to large shrubs: stems woody, erect, up to 4 m tall, 5 mm in diameter at 5 cm below apex, bark rugose where internodes close, or smooth and striated where internodes well spaced on rapidly elongating branches, reddish-brown or green, glandular-resinous, becoming gray-brown,

with resin flaking as a yellowish or whitish pulverulence, internodes 0.2–2.3 cm long, leaf scars prominent, pith green or red; branches few or numerous, short, in upper leaf axils, somewhat flattened, lenticels elongated, erumpent, nodes slightly swollen, axillary buds densely or sparsely covered by caducous reddish articulated trichomes, trichomes occasionally adhering to young leaves and inflorescences.

Leaves alternate, when well separated on rapidly growing branches, or approximate and conferted at branch apices; petioles subsulcate, 1–5 mm long, ca 1 mm in diameter, green or reddish, glandular-resinous; blades spathulate, obovate or elliptic, 1.0–3.4 cm long, 1.0–1.7 cm wide, coriaceous, base acute to cuneate, margin entire to coarsely crenate-dentate at the obtuse or subtruncate apex, adaxial surface smooth, nitid, dark green, glabrous but glandular, veins immersed, abaxial surface light green or brownish, glabrous, but glandular, with prominent brown or red veins.

Inflorescences axillary, of 1(–4) flowers, often equaling the subtending leaves: peduncles terete, 1–4 mm long, ca 1 mm in diameter, glandular-resinous; bracts 2, at apex of peduncle, filiform to narrowly lanceolate, 4–9 mm long, ca 1 mm wide, green or reddish, glabrous, glandular-resinous; pedicels terete, 3–9 mm long, ca 1 mm in diameter, green or reddish; floral tube turbinate, 2–5 mm long, 2–3 mm wide, green or reddish, glabrous, nitid, glandular-resinous; calyx erect or slightly spreading, 5-lobed, lobes connate for ca 1 mm, aestivation valvate, each lobe linear or subulate, sulcate, 7–15 mm long, 1–2 mm wide at base, apex acuminate, both sides green or reddish, glabrous, and nitid, glandular-resinous, with a prominent keel on each lobe base; corolla (Figure 16j) tubular, suburceolate, 1.3–1.6 cm long, base narrow ca 3 mm across, 4–5 mm wide below the middle then narrowing to the mouth, ca 3 mm wide; outside red or red-orange, glabrous, nitid, glandular-resinous, inside yellow, glabrous, limb slightly oblique and somewhat spreading, 5-lobed, 3–4 mm wide, lobes semiorbiculate, 1–2 mm long, red, glabrous, margin entire, glandular; stamens 4, adnate to base of corolla for about 1 mm, exserted beyond mouth, at anthesis for up to 3 mm, filaments linear, 1.0–1.3 cm long ca 1 mm in diameter, yellow-green, glabrous, anthers globose, ca 1 mm long, yellow, glabrous, coherent in 2 pairs, pollen grains isopolar, prolate, size small (21.2–23.3 μm long at the polar axis, 11.2 μm wide at the equatorial axis), amb almost circular, tricolpate, colpi ca 21 μm long, ca 1 μm wide, sexine reticulate (Figure 18c), hetero-brochate, staminode ca 3 mm long; ovary fully inferior, apex pilose, disc sinuate-annular, yellow-green, glabrous, ca 2 mm across, style linear 8–12 mm long, ca 1 mm in diameter, yellow-green or reddish, pilose, stigma capitate, somewhat bilobed, reddish, glandular.

Capsule obovate-turbinate to subglobose, 5–6 mm long, 4–5 mm wide, with 5 prominent costae; seeds fusiform to linear, striate, ca 1 mm long, reddish-brown.

TYPE-COLLECTION.—Between Boucan Calice and Hoyo de Pelempito, Dominican Republic, Alain Liogier 13871 (NY, holotype, Figure 36).

DISTRIBUTION AND ECOLOGY.—Gesneria pulverulenta is endemic to the Sierra de Baoruco of the Barahona Peninsula of southern Hispaniola (Figure 27), where it has been collected from rocky limestone cliffs and deep gorges in pine woods and thickets at elevations from 800–1300 m. In the wild, plants have been collected in flower from February to August. In the greenhouse, plants bear inflorescences all during the year.

SPECIMENS EXAMINED.—HISPANIOLA. DOMINICAN REPUBLIC. Province of Pedernales: trail between Pedernales and Aceitial, 4200 ft, 8–12 August 1946, R. Howard & E. Howard 8120 (NY, holotype of Gesneria saxatilis Alain; BM, GH, P, S, US, isotypes); Aceitillar Cayo, Sierra de Baoruco, 1300 m, 9 February 1969, Alain Liogier 13672 (GH, NY); Aceitillar, 28 March 1956, J. Jiménez 3240 (BH, E, RDJ, US); Camote, Aceitillar, 31 March 1961, E. Marcano 4518 (RDJ, US); Aceitillar, 23 March 1967, E. Marcano 5261 (BH, NY, RDJ), T. Talpey 81 (BH); Aceitillar region, 26 February 1971, Alain Liogier 17913 (NY); between Boucan Calice and Hoyo de Pelempito, E of Aceitillar, Sierra de Baoruco, 800 m, 13 February 1969, Alain Liogier 13871 (NY, holotype of Gesneria pulverulenta Alain); Hoyo de Pelempito, 800 m, 3–8 July 1971, Alain Liogier 18132 (NY, holotype of Gesneria filisepala Alain; GH, US, isotypes). CULTIVATED: Cornell University, G-1034, 3 November 1970, L. Skog 1751 (BH).