Amanoa, Aublet, 1775

Villanueva-Tamayo, Boris, Corrales Bravo, Lina M. & Aymard-Corredor, Gerardo A., 2024, A New Timber Species of Amanoa (Phyllanthaceae; Phyllanthoideae) Endemic to Colombia’s Montane Forests and Critically Endangered, with an Updated Key for the Species of the Genus, Phytotaxa 672 (2), pp. 187-198 : 195

Key to Neotropical species of Amanoa

(Modified from Secco, 2014)

1. Shrubs mostly <2 m tall; leaves strongly clustered, apex rounded or slightly emarginate, with a marginal crustaceous band well evident on the adaxial surface ...................................................................................... A. cupatensis ( Brazil, Colombia, Venezuela)

- Small (up 4 m) to medium (12–35 m) trees or shrubs> 2 m tall; leaves more evenly spaced, apex acuminate, acute, or obtuse, not emarginate, the marginal crustaceous band on the adaxial surface lacking or only faintly evident ..................................................2

2. Stamens basally connate, forming an androphore..............................................................................................................................3

- Stamens free .......................................................................................................................................................................................6

3. Rachis of the inflorescence glabrous or glabrescent to sparsely pubescent .......................................................................................4

- Rachis of the inflorescence pubescent or densely tomentose.............................................................................................................5

4. Inflorescence an elongate, erect, spike-like, with broadly spaced fascicles of numerous flowers (three of more flowers per bracteole); pedicels 4–5 mm long......................................................................... A. caribaea (Antilles: Dominica and Guadeloupe)

- Inflorescence congested, but never more than two flowers per bracteole; pedicels sessile to 0.5–1 mm long.................................... ..................................................................................................................................................................... A. condorensis ( Ecuador)

5. Trees to 24 m tall; branches lenticellate, with a ferruginuous tomentum; leaves oblong to oblong-elliptic; stipules 1.3–1.8 mm long; petioles 4.3–6.4 mm long; inflorescence raquis lenticellate, ferruginuous trichomes scattered; pistillate flowers pedicellate, pedicel 5–5.8 mm long; sepals 3.8–4.9 mm long, oblong to elliptic; ovary 2.4–3.5 mm long................................. A. tolimensis ( Colombia)

- Shrubs or small trees up 12 m tall; branches not lenticellate, glabrous; leaves elliptic or oval-lanceolate; stipules 2–2.5 mm long; petioles 10–15 mm long; inflorescence raquis not lenticellate, covered by ferrugineous trichomes; pistillate flowers subsessile, pedicel ca. 1 mm long; sepals 2–2.5 mm long, elliptic-ovate; ovary ca. 1.5 mm long ........................................................................ ..................................................................................................................................... A. almerindae ( Brazil, Colombia, Venezuela)

6. Leaf margin revolute throughout or just at the base...........................................................................................................................7

- Leaf margin flat ................................................................................................................................................................................11

7. Plants dioecious, leaves with a faintly evident marginal band on the abaxial surface; staminate flowers long-pedicellate (5–6.5 mm long).......................................................................................................................... A. glaucophylla ( Brazil. Colombia, Venezuela)

- Plants monoecious, leaves without crustaceous marginal band on the abaxial surface; staminate flowers sessile or shortly pedicellate (1–2 mm long) ....................................................................................................................................................................................8

8. Staminate flowers pedicellate (> 1 mm long)......................................................................................................................................9

- Staminate flowers sessile..................................................................................................................................................................10

9. Inflorescence with lenticels on rachis, leaves chartaceous, with a network of shiny, translucent “islands” and isolated punctations visible under magnification, especially on the abaxial surface; secondary veins barely evident................... A. marapiensis ( Brazil)

- Inflorescence without lenticels on rachis, leaves coriaceous or subcoriaceous, no “islands” present, evident veins on both sides, forming well-defined arches, more evident on the abaxial face....................................................... A. guianensis (Central America: Belize to Panamá, Antilles to central and South America: Colombia, Venezuela, Perú, Ecuador, French Guiana, Guyana y Brazil)

10. Leaves spreading; inflorescence stout, the rachis sinuous; plants of elevations below 500 m ............................................................ .................................................................................................................................................... A. sinuosa ( Brazil, Colombia, Perú)

- Leaves stiffly erect; inflorescence slender, the rachis straight; plants of elevations above 1500 m at Guayana Shield highlands (Tepuis).................................................................................................................................................... A. steyermarkii ( Venezuela)

11. Plants dioecious; inflorescence 20–40 cm long................................................................................................ A. anomala ( Ecuador)

- Plants monoecious; inflorescence less than 20 cm long...................................................................................................................12

12. Young branches tomentose; inflorescence rachis pubescent..................................... A. neglecta ( Brazil, French Guiana, Suriname)

- Young branches and inflorescence rachis glabrous..........................................................................................................................13

13. Leaves markedly discolorous (in dry herbarium material), the abaxial surface dark brown to olivaceous; fruit with a very thin pericarp, mericarps with fine veinlets extending beyond the margins .............................................................. A. gracillima ( Brazil)

- Leaves subtly discolorous (in dry herbarium material), the abaxial surface light brown; fruit with a thick pericarp, mericarps without fine veinlets extending beyond the margins........................................................................................................................14

14. Inflorescence glomerules quite close together, especially in the distal portion of the rachis; style present, 2–2.5 mm long; fruit markedly trigonous, with dilated mericarps ..................... A. congesta ( French Guiana, Brasil, Amapa ́, Amazonas and Pará states).

- Inflorescence glomerules more distant from one another, spaced 1.5–5 mm apart; style absent or subsessile; fruit slightly trigonous, with compressed mericarps ..............................................................................................................................................................15

15 Leaves brownish when dried, glossy and sericeous on the abaxial surface, with brilliant punctations; inflorescence little branched; staminate flowers with an undulate disc; fruit with flattened mericarps.............................................................................................. ............................................................................................................ A. oblongifolia ( Bolivia, Brazil, Colombia, Perú, Venezuela)

- Leaves reddish when dried, not glossy not sericeous on the abaxial surface, punctations absent; inflorescence well branched; staminate flowers with a lobate disc; fruit with the mericarps slightly dilated ..................... A. nanayensis ( Brazil, Colombia, Perú)