Oxandra sphaerocarpa R.E.Fr.

Junikka, L., Maas, P. J. M., Maas-van de Kamer, H. & Westra, L. Y. Th., 2016, Revision of Oxandra (Annonaceae), Blumea 61 (3), pp. 215-266 : 253-257

23. Oxandra sphaerocarpa R.E.Fr. — Fig. 21e, f, 23; Map 12

Oxandra sphaerocarpa R.E.Fr. (1934) 198. — Type: Ll. Williams 475 (holo F), Peru, Loreto, Lower Río Nanay, S bank of Río Amazonas , 28 May 1929.

Tree 6–40 m tall, 10–50 cm diam (‘with low plank buttresses’, Daly et al. 5621); young twigs rather densely covered with appressed hairs, soon glabrous. Leaves: petiole 2–4 mm long, 1–2 mm diam; lamina narrowly elliptic to narrowly ovate, 8–20 by 3–7 cm (leaf index 2.7–3.8), chartaceous, rather densely verruculose to not verruculose above and below, dull and brown to brownish grey green above, pale brown to brown below, mostly densely covered with appressed to erect hairs along primary vein above, sparsely covered with appressed hairs below, base acute to obtuse, often oblique and sometimes with two angular to tooth-like projections on either side, apex acute to acuminate (acumen 10–15 mm long), primary vein impressed to flat above, secondary veins distinct, 12–16 on either side of primary vein, slightly raised above, angle of secondary veins with primary vein 65–80°, smallest distance between loops and margin 2–5 mm, tertiary veins slightly raised above, reticulate. Flowers in 1–3-flowered inflorescences; flowering pedicels 2–6 mm long, 0.5–1 mm diam, fruiting pedicels 4–9 mm long, 1–3 mm diam, sparsely covered with appressed hairs to glabrous; bracts 4–6, depressed ovate, 1–2 mm long, outer side densely to rather densely covered with appressed hairs; flower buds

Map 12 Distribution of Oxandra sphaerocarpa (●) and O. venezuelana (●). Fig. 22 Oxandra sessiliflora R.E.Fr. Fruiting twig (B.A.S. Pereira et al. 1600, U). Fig. 23 Oxandra sphaerocarpa R.E.Fr. Fruiting twig (Prance et al. 24514, U).

Fig. 24 Oxandra venezuelana R.E.Fr. Fruiting twig (Deago & Carrasquilla 536, U).

ellipsoid; sepals broadly to shallowly ovate-triangular, 1–1.5 by 1–3 mm, outer side rather densely covered with appressed hairs; petals pale cream to cream, oblong-elliptic, 4–10 by 2–5 mm, outer side rather densely covered with appressed hairs; stamens 15–20, 2.5–3 mm long, apex of connective narrowly triangular; carpels ≤ 20. Monocarps 2–15, green to reddish yellow, maturing red, black to bluish black in vivo, black in sicco, globose, sometimes ellipsoid, 10–17 by 10–13 mm, glabrous, apex apiculate (apiculum to c. 1 mm long), wall c. 1 mm thick, stipes 6–16 by 1 mm. Seed broadly ellipsoid to ovoid, 9–12 by 7–10 mm, brown to pale brown, surface minutely pitted to transversely striate, ruminations spiniform.

Distribution — Brazil (Amazonas), Ecuador (Pastaza), Peru (Loreto, Pasco, Ucayali).

Habitat & Ecology — In periodically inundated (restinga, tahuampa, várzea) forest, at clayey soil. At elevations of up to c. 150 m. Flowering: October; fruiting: February to May, October, November.

Vernacular names — Peru: Acara-wasca (Ll. Williams 475, 478), Espintana ( Daly et al. 5068, Freitas 10, T.D. Pennington et al. 17022, Valcarcel 539-2), Espintana roja ( Daly et al. 5621), Yahuayachi caspi (Rimachi Y. 271).

Field observations — Flowers sweet-scented (T.D. Pennington et al. 17022); frutos con aroma a limón (Zak 4190, Ecuador).

Note — Oxandra sphaerocarpa can be distinguished in fruit by extremely long stipes up to 16 mm long and in flower by elongate, ellipsoid buds and hairy petals. The primary vein of the leaves is often densely covered with appressed to erect hairs above.