Eperua Aublet (1775: 369)

Fortes, Elenice A., Dos, Ilka P., Steege, Hans Ter, Aymard, Gerardo, Secco, Ricardo De S., Martins-Da-Silva, Regina Célia V. & Mansano, Vidal F., 2023, A taxonomic revision of the genus Eperua (Leguminosae, Detarioideae, Detarieae), Phytotaxa 617 (1), pp. 1-127 : 19-22

Eperua Aublet (1775: 369) .

Type:— Eperua falcata Aublet (1775: 369) .

Parivoa Aublet (1775: 756) . Type:— Parivoa grandiflora Aublet (1775: 757) [≡ Eperua grandiflora ( Aublet 1775: 757) Baillon (1870: 110)]

Dimorpha Schreber (1791: 493) nom. illeg. superfl.

Panzera Willdenow (1799: 540) nom. illeg. superfl. Type:— Panzera falcata ( Aublet 1775: 369) Willdenow (1799: 540) [≡ Eperua falcata Aublet (1775: 369)]

Small to very large trees (2.0–50.0 m tall); trunk with bark lenticellate, fissured, striate, scaled, or smooth; branchlets glabrous, rarely puberulent, puberulous to strigulose in E. oleifera . Stipules 2, intrapetiolar, entirely joined, joined at the base, or free, pellucid-punctate, foliaceous or non-foliaceous, when foliaceous ovate-falcate, obovate-falcate, elliptic-falcate, falcate to semiorbicular, base attenuate, subcordate to cordate, when non-foliaceous ovate to lanceolate, base truncate, persistent to caducous. Leaves alternate and distichous, paripinnate, 1- to 7-jugate, usually glabrous, petioles, rachis and petiolules terete to canaliculate, glabrous, rarely puberulous in E. oleifera ; blades coriaceous to chartaceous, glabrous, pellucid-punctate to epunctate, discolorous or not, equilateral, or inequilateral and falcate, elliptic, ovate to lanceolate, apex usually attenuate to acuminate, but acute, obtuse to rounded in two species, base symmetrical to asymmetrical, or oblique, usually lower pair base more rounded and upper pair base more cuneate, margin flat to revolute, secondary venation with one or two intramarginal veins, usually vein closer to the margin not continuous, main vein straight or curved in falcate leaflets, prominent to depressed on the adaxial side, 10–40 secondary veins, spacing uniform, angle uniform, intersecondary veins conspicuous, tertiary veins regular polygonal reticulate, conspicuous to inconspicuous, areoles smaller and concave or larger and plane. Inflorescences a raceme or panicle, terminal, axillary, sometimes ramiflorous or cauliflorous, short and erect or long and pendulous, glabrous or with indumentum, lateral racemes alternate, distichous or spirally arranged, peduncle sessile up to 4.0 cm long in short and erect inflorescences, or up to 3.0 m long in long and pendulous inflorescences; one bract at the base of the pedicel; one pair of bracteoles attached to different portions of the pedicels, imbricate, free, not enclosing the developed flower buds, apex gland present or absent. Flowers alternate and spirally arranged, pedicellate, hypanthium cup-shaped or tubular, inner wall with nectar-producing glands; sepals four, free, unequal, the outer ones larger, apex gland present or absent, inner surface glabrous, outer surface glabrous or with indumentum, inner sepals scarious marginally; petals five, adaxial petal superinvolute forming a tube or involute but not forming a tube, flabellate, oblate to broadly obovate, apex rounded to truncate, base attenuate to truncate, white, cream, greenish, lilac, purple, pink to red, glabrous or with indumentum in E. venosa , other four petals reduced to petalodia, up to 7.5 mm long; stamens 10, all fertile or up to 5 staminodial, inserted when the adaxial petal is tubular, exserted in the non-tubular ones, filaments heteromorphic, joined basally in a tube, or in a diadelphous sheath with dorsal one free, usually glabrous on the free part, anthers all equal or dimorphic; ovary with stipe inserted centrally in the hypanthium, glabrous or with indumentum, style usually longer than the largest filaments, glabrous, adaxial groove present, stigma obtuse to capitate, entire or 2-lobed. Fruit legume, with stipe, equilateral or inequilateral and falcate, wood, flattened, glabrous or with indumentum, dehiscent, valves twisted after opening, seeds 1-few, flattened.

Etymology:— Eperua is derived from the fruit shape of its type species, E. falcata . The term “eperu” is a Galibi name for the fruit of E. falcata ( Aublet 1775) , which translates to “sabre” in English. This refers to a curved-blade sword ( Collins 2023), resembling the curved shape of the fruit.

Key to all species, subspecies and varieties of Eperua

1. Leaflets secondary venation with one intramarginal vein very close to the margin .......................................................................... 2

- Leaflets secondary venation with two intramarginal veins or, if one intramarginal vein, vein not very close to the margin............ 7

2. Inflorescence long and pendulous, corolla non-tubular, fruits elliptic-falcate, narrowly elliptic-falcate, or lanceolate-falcate ........ 3

- Inflorescence short and erect, corolla tubular, fruits oblanceolate to obovate, never falcate ............................................................ 5

3. Blades minutely pellucid-punctate, not all areoles have one dot, inflorescences with lateral racemes pendulous, adaxial petal non-white and glabrous................................................................................................................................................................ E. falcata

- Blades pellucid-punctate, each areole has at least one conspicuous dot, inflorescences with lateral racemes erect to patent, adaxial petal non-white and sericeous at the base, or white and glabrous......................................................................................................4

4. Petals deep-rose, sericeous at the base ................................................................................................................................. E. venosa

- Petals white, glabrous...................................................................................................................................................... E. leucantha

5. Leaflets abaxial surface densely papillate-ceriferous, inflorescence glabrous................................................................. E. purpurea

- Leaflets abaxial surface not densely papillate-ceriferous, inflorescence strigose to tomentose, rarely pubescent ....... 6 ( E. oleifera )

6. Treelet, shrub, leaflets basal pair with base obtuse to rounded, rarely cordate or subcordate ...................... E. oleifera var. oleifera

- Tall tree, leaflets basal pair with base rounded, subcordate to cordate .................................................... E. oleifera var. campestris

7. Inflorescence long and pendulous, corolla non-tubular ..................................................................................................................... 8

- Inflorescence short and erect, corolla tubular or non-tubular........................................................................................................... 10

8. Inflorescence glabrous, fruits glabrous................................................................................................................................. E. glabra

- Inflorescence tomentulose, coppery, fruits tomentose, coppery............................................................................... 9 ( E. rubiginosa )

9. Leaves (2–)3(–4)-jugate, pedicel 0.6–2.0 mm in diameter ................................................................. E. rubiginosa var. rubiginosa

- Leaves (3–)4–5-jugate, pedicel 2.0– 3.3 mm in diameter ................................................................... E. rubiginosa var. grandiflora

10. Corolla non-tubular, stamens exserted, fruits oblanceolate-falcate.................................................................................................. 11

- Corolla tubular, stamens inserted, fruits oblong, obovate, orbicular, elliptic, never falcate ............................................................ 15

11. Flowers with ovary tomentose, fruit tomentose or tomentulose ...................................................................................................... 12

- Flowers with ovary glabrous, fruits glabrous................................................................................................................................... 14

12. Main vein depressed on the adaxial surface, bracteoles 9.8–12.7 × 6.5–9.8 mm, persistent, stamens entirely glabrous .................... .................................................................................................................................................................................... E. cerradoensis

- Main vein prominent on the adaxial surface, bracteoles 1.9–5.0 × 2.3–4.2 mm, caducous, stamens sheath non-glabrous............. 13

13. Stipules free, blades pellucid-punctate, rarely inconspicuous pellucid-punctate, stamens sheath tomentose ................ E. duckeana

- Stipules joined at the base, blades inconspicuous pellucid-punctate to epunctate, stamens sheath irregularly tomentose.................. ......................................................................................................................................................................................... E. reddeniae

14. Stipules entirely joined, leaflets with main vein depressed on the adaxial surface, stamens joined basally in a tube, glabrous......... ............................................................................................................................................................................................... E. froesii

- Stipules free, leaflets with main vein prominent on the adaxial surface, stamens joined basally in a diadelphous sheath 9+1, irregularly tomentose ........................................................................................................................................... E. schomburgkiana

15. Apex of the leaflets acute, obtuse, rounded to emarginate, stamens glabrous ................................................................................. 16

- Apex of the leaflets attenuate, acuminate to caudate, stamens non-glabrous .................................................................................. 17

16. Treelets, leaflets elliptic to obovate, bracteoles 7.0–8.0 × 7.0–8.0 mm, flowers with hypanthium 5.0 mm long, ovary more than twice (7–8 mm long) longer than the stipe (2.0–3.0 mm long)....................................................................................... E. banaensis

- Tall trees, leaflets oblong to elliptic, bracteoles 2.0 × 1.0–2.0 mm, flowers with hypanthium 2.0–3.0 mm long, ovary almost as long (5.0 mm long) as the stipe (4.0 mm long) ........................................................................................................................ E. obtusata

17. Inflorescence glabrous...................................................................................................................................................................... 18

- Inflorescence non-glabrous (puberulous, strigulose, tomentose, pubescent, or strigose) ................................................................ 21

18. Leaflets blades with margin revolute, bracteoles caducous ................................................................................... 19 ( E. glabriflora )

- Leaflets blades with margin flat, bracteoles persistent..................................................................................................................... 20

19. Flowers with ovary always glabrous ................................................................................................... E. glabriflora var. glabriflora

- Flowers with ovary glabrous or tomentose in the same inflorescence......................................... E. glabriflora var. gynopubescens

20. Leaves 3–5-jugate, bracteoles attached to the lower portion of the pedicels ..................................... E. jenmanii subsp. sandwithii

- Leaves 2–3-jugate, bracteoles attached at the base of the hypanthium................................................. E. grandiflora subsp. ciliata

21. Lower pair of leaflets with base subcordate to cordate, ovary tomentose to villous.................................................. E. manausensis

- Lower pair of leaflets with base obtuse to rounded, rarely subcordate, ovary glabrous or sericeous in E. grandiflora subsp. guyanensi s ........................................................................................................................................................................................ 22

22. Stipules joined at the base, leaves 3–5-jugate, bracteoles attached to the lower portion of the pedicels............................................. .............................................................................................................................................................. E. jenmanii subsp. jenmanii

- Stipules free, leaves 2–3(–4)-jugate, bracteoles attached to the lower middle portion of the pedicels, or to the higher portion of the pedicels, or at the base of the hypanthium ....................................................................................................................................... 23

23. Inflorescence puberulous, bracteoles attached to the lower middle portion of the pedicels ................................................. E. bijuga

- Inflorescences pubescent to tomentose, sometimes puberulous, bracteoles attached to the higher portion of the pedicels or at the base of the hypanthium........................................................................................................................................ 24 ( E. grandiflora )

24 Leaflets with margin revolute, flowers with ovary sericeous, fruits puberulous ......................... E. grandiflora subsp. guyanensis

- Leaflets with margin flat, flowers with ovary glabrous, fruits glabrous ...................................... E. grandiflora subsp. grandiflora