Tetrameranthus globuliferus Westra in Maas et al.

Westra, Lubbert Y. T. & Maas, Paul J. M., 2012, Tetrameranthus (Annonaceae) revisited including a new species, PhytoKeys 12, pp. 1-21 : 7-9

Tetrameranthus globuliferus Westra in Maas et al. Fig. 3D-G Map 2

Tetrameranthus guianensis Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, ser. C. 91: 262, figs 20-22. 1988.

Type.

Lawesson et al. SEF 8779 (holotype AAU; isotypes AAU, QCA, QCNE, U), Ecuador, Orellana: Añangu, Parque Nacional Yasuní, 260-350 m, May-June 1986.

Description.

Medium-sized tree,>10 cm diam., young twigs and petioles densely covered with pale brown, stellate hairs>0.5 mm long. Leaves: petioles 4-8 mm long, 4-6 mm diam., lamina narrowly obovate, 27-37 by 9-15 cm (index 2.8-2.9), chartaceous, shiny green above in vivo, greenish brown above, pale greenish brown to brown below in sicco, rather densely covered with stellate hairs>0.5 mm long on primary vein, to rather sparsely so on smaller veins on both sides, base acute to attenuate, to obtuse or rounded at the extreme base, apex acute to acuminate (acumen to c. 10 mm long), primary vein flat to slightly raised above, secondary veins 20-25 on either side of primary vein, flat to impressed above, loop-forming, shortest distance between loops and margin 1.5-3 mm, or not loop-forming, tertiary veins flat to raised above, percurrent to more or less reticulate. Inflorescences 1-flowered; peduncles 3-5 mm long, 3-4 mm diam., fruiting peduncle c. 5 mm diam., bracts [4?] narrowly oblong or narrowly triangular, 4-5 mm long, falling after flowering, pedicels {18-30} mm long, {4-6} mm diam., densely covered with brownish, stellate hairs; flowers with perianth in 6-merous whorls, cream with the inner petals yellow at the inner base in vivo; sepals broadly ovate-triangular, connate at the very base, {6-11} by {5-10} mm; outer petals elliptic to ovate, {30-45} mm long, {10-25} mm wide, with small callus at the inner base; inner petals {30-40} mm long, {5-10} mm wide, more or less narrowed toward the base, with larger callus, outer side of petals densely covered with stellate hairs, the callus on the inner side glabrous; stamens {2-2.5} mm long, connective shield flat, cushion-shaped. Monocarps 2-7, globose or almost, green in vivo, brown in sicco, c. 40 mm diam., wall strongly shriveled in sicco. Seeds 1-2 per monocarp, 25-30 by 15-20 mm.

Distribution.

Ecuador (Orellana). Only known so far from Parque Nacional Yasuní.

Habitat and ecology.

In rain forest on terra firme. At elevations of 200-400 m. Flowering recorded in November; fruiting recorded in May, June, August.

Additional specimens examined.

Ecuador. Orellana: NW corner of Parque Nacional Yasuní, 355-365 m, Korning & Thomsen 47626 (AAU, U); Parque Nacional Yasuní, E of Juan Tapuy’s finca, 250 m, Pitman & Delinks 1440 (MO, QCA,U).

Note.

The description of the flower was largely made from a very recent photograph of a freshly collected twig of Pérez & Santillán 4404 (QCA). Measurements between {} were made on two flowers preserved in alcohol kept in QCA and were kindly supplied to us by Álvaro J. Pérez C.

Á. J. Pérez also reports to us a clustered occurrence of Tetrameranthus globuliferus : he found few individuals all close to the one that he collected, but did not spot any more around the trails of the Yasuní Scientific Station.

The species has been listed as near-threatened on the IUCN red list ( Muriel and Pitman 2003). In an important paper on global conservation significance of Yasuní National Park Tetrameranthus globuliferus is documented as one of five species (and one of only two woody species) not found anywhere else in the world ( Bass et al. 2010).

Figures

Map 2. Distribution of Tetrameranthus globuliferus Westra (○), Tetrameranthus laomae D. R. Simpson (□), Tetrameranthus macrocarpus R. E. Fr. (◉), and Tetrameranthus umbellatus Westra (◆).

Figure 3. Tetrameranthus guianensis Westra & Maas A Single-flowered inflorescence after shedding of perianth and stamens B A twig C Ripe fruit, also sectioned to show seed. Tetrameranthus globuliferus Westra D, E Twig with inflorescences (Perez C. & Santillan 4404, QCA) F, G Flower seen from the side and from above (same). A-C Photos by D. Sabatier, D-G Photos by A. J. Perez C.