159. Guatteria tacarcunae Erkens & Maas, sp. nov. — Fig. 70d, 80; Map 35

Guatteriae darienensis affinis sed pedicellis et stipitibus minoribus ramulisque pilis adpressis nec erectis obtectis differt. —

Typus: Gentry & Mori 13678 (holo MO), Panama, Darién, top of Cerro Mali, 1400 m, 17 Jan. 1975.

Tree 5–20 m tall, diam not recorded; young twigs densely covered with erect hairs to c. 2 mm long, soon glabrous. Leaves: petiole 5–10 mm long, 1–3 mm diam; lamina elliptic to narrowly elliptic, 8–20 by 4–7 cm (leaf index 2–3.2), chartaceous, not verruculose, shiny, greyish brown to brown above, brown below, rather densely covered with appressed hairs above, soon completely glabrous, sparsely to rather densely covered with appressed hairs to c. 2 mm long below, base acute to obtuse, apex acute to acuminate (acumen 5–10 mm long), primary vein impressed above, secondary veins distinct, 7–12 on either side of primary vein, slightly impressed above, smallest distance between loops and margin 1–2 mm, tertiary veins slightly raised to flat above, percurrent. Flowers in 1-flowered inflorescences in axils of leaves; pedicels 15–30 mm long, 1–1.5 mm diam, fruiting pedicels 1.5–2 mm diam, densely covered with erect hairs, articulated at 0.2–0.3 from the base, bracts 5–6, soon falling, not seen; flower buds depressed ovoid; sepals basally free, broadly to shallowly ovate-triangular, 4–6 by 4–7 mm, finally reflexed, outer side densely covered with appressed hairs; petals green in vivo, elliptic-oblong, 10–20 by 5–7 mm, outer side densely covered with appressed hairs; stamens c. 1 mm long, connective shield papillate. Monocarps (only young ones seen) 25–50, greenish white with red stripes to green in vivo, brown in sicco, ellipsoid, 5–7 by 3–5 mm, sparsely covered with appressed hairs, apex apiculate (apiculum <0.5 mm long), wall 0.1–0.2 mm thick, stipes 3–10 by 1 mm. Seed not seen.

Distribution — Panama (Darién).

Habitat & Ecology — In lower montane forest or tropical wet forest. At elevations of 1400–1600 m. Flowering: January, February; fruiting: January, February, July.

Vernacular names — Not recorded.

Other specimens examined. PANAMA, Darién, Cerro Mali, 10 year old second growth on site of Old Helipad, 17 Jan. 1975, Gentry & Mori 13660 (MO);vicinity Cerro Tacarcuna,summit camp,along stream N of camp, 1550– 1600 m, 1 Feb. 1975, Gentry & Mori 14052 (MO); Cerro Tacarcuna W ridge, trail toward Río Pucura,just below summit camp, 1500–1600 m, 2 Feb.1975, Gentry & Mori 14123 (MO); idem, 5 Feb. 1975, Gentry & Mori 14149 (MO); S slope of westernmost peak of Cerro Tacarcuna massif, 1500–1600 m, 22 July 1976, Gentry et al. 16953 (MO).

Note — Guatteria tacarcunae looks quite similar to G. darienensis, differing only in shorter pedicels (15–30 vs 30–60 mm) and shorter stipes (3–10 vs 7–15 mm) and having its young twigs covered with erect instead of appressed hairs. Guatteria tacarcunae is, moreover, found at higher elevations (1400–1600 vs 20–800 m).