Eperua bijuga Martius ex Bentham (1870: 226)

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 : 26-29

2. Eperua bijuga Martius ex Bentham (1870: 226)

( Figures 10 , 17 , 18 )

Type (designated by Cowan 1975): — BRAZIL. Pará : In sylvis inundatis ad insulam Marajo, May 1820, Martius C. F. P. s.n. (lectotype K [000555103] image!, isolectypes LE [00002232] image!, M [0215266] image!, M [0215267] image!, M [0215268] image!, M [0215270] image!) .

Tree 3.0–33.0 m tall. Trunk 18.0– 31.8 cm in diameter, bark brown, striate. Stipules 1.1–14.2(–18.3) × 0.5–10.0(– 13.0) mm, free, foliaceous or non-foliaceous, caducous to persistent. Leaves 2(–3)-jugate; petioles 0.6–3.1(–6.8) cm long; rachis (1.3–)2.0–6.4(–9.3) cm long; petiolules 4.4–12.3 mm long; blades (3.1–)6.4–17.6(–22.4) × 2.8–9.2 cm, coriaceous, glabrous, sparsely pellucid-punctate, sometimes pellucid-punctate or epunctate, slightly discolorous, equilateral, lower pair elliptic to ovate, rarely lanceolate, smaller, upper pair elliptic, apex attenuate to acuminate, sometimes acute, mucronate, base symmetrical, rarely slightly asymmetrical, with one pair of glands, lower pair base obtuse, rarely rounded, subcordate or cordate, upper pair base obtuse, rarely rounded or cuneate, margin flat, secondary venation with two intramarginal veins, vein closer to the margin not continuous, sometimes continuous, main vein straight, prominent near the base, sometimes depressed, on the adaxial surface, tertiary veins conspicuous, areoles smaller, concave. Inflorescences terminal, rarely axillary or ramiflorous, panicle or raceme, erect, puberulous, trichomes white, 1.2–3.6 cm long, lateral racemes 0.9–2.6 cm long, alternate and spirally arranged or distichous; bracts 3.0–3.7 × 4.5 mm, oblate, apex gland absent, puberulous, trichomes white, caducous, rarely persistent; bracteoles 3.3–5.0 × 2.1–6.3 mm, oblate, sometimes broadly ovate, apex gland absent, puberulent externally, glabrous within, sometimes puberulent within, trichomes white, persistent, rarely caducous, attached to the lower middle portion of the pedicels; pedicel 3.3–9.5 mm long, 1.0– 2.2 mm in diameter, not twisted, puberulent, trichomes white; buds 1.0– 2.3 cm long, 0.6–1.7 cm in diameter, puberulous, trichomes white. Flowers: hypanthium 1.6–3.6 mm long, 2.5–7.6 mm in diameter, cup-shaped, inequilateral, puberulent to puberulous, trichomes white; sepal 1.3–3.0 × 0.5–1.3 cm, oblong to obovate, unequal, the outer ones more robust, the dorsal one larger, cucullate, apex gland absent, green, puberulent, inner sepals scarious marginally, trichomes white; adaxial petal 3.8–8.0 × 3.0– 7.3 cm, flabellate, tubular, apex rounded, crisped, base attenuate, lilac with white nectar guide, pink, rose, purple, purple-red to red, glabrous; petalodia 0.8–7.3 × 0.4–1.4 mm; stamens inserted, joined basally in a diadelphous sheath, dorsal one free, longer filaments 3.0– 5.2 cm long, shorter filaments 1.7–3.1 cm long, sheath inequilateral, shorter side 5.5–17.3 mm long, longer side 8.9–24.0 mm long, sheath puberulous, free filament glabrous, trichomes white, anthers 3.2–5.0 × 0.7–2.3 mm, rectangular; ovary 5.3–11.8 × 1.8–5.1 mm, falcate, rarely obovate or oblong-obovate, glabrous, 1? ovule, stipe 2.8–9.5(–13.4) mm long, glabrous, style 2.4–3.8 cm long, stigma capitate, sometimes obtuse. Legumes 7.6–15.4 × 4.6–8.6 cm, stipe 1.0– 2.5 mm long, oblong, apex obtuse, sometimes truncate, rarely rounded, apiculate, margin thickened, brown, rarely redbrown or dark-brown, with transversal veins, glabrous, foveate. Seeds 1–2 per fruit, 4.0–7.3 × 3.2–4.7 cm, ovate to inequilateral ovate, dark-brown.

Phenology:— Flowering from March to August; fruiting throughout the year.

Distribution:— Brazil (Pará and Amapá), and one collection from French Guiana without locality.

Habitat:— Floodplain forests, mainly in igapó forest, but also in várzea forest. It is also found in the Amapá ( Brazil) savannas in river-associated vegetation.

Conservation status:— Categorized as Least Concern (LC) according to the IUCN criteria ( IUCN 2012, IUCN Standards and Petitions Committee 2022). The estimated extent of occurrence for the species is 129,115.212 km 2 and the estimated area of occupancy is 148.000 km 2.

Occurrence in protected areas:— Floresta Nacional de Caxiuan„ ( Brazil, Pará) and Floresta Nacional do Amapá ( Brazil, Amapá) ( Silva et al. 2015).

Etymology:— The specific epithet relates to its 2-jugate leaves.

Vernacular names:— apá (Rabelo B.V. et al. 3307, Rosa N.A. 1288), muirapiranga (Oliveira E. 4929, Cruz E.D. 1123), muirapironga (Oliveira E. 4929).

Uses:— it is described as potentially ornamental (Souza L.A.G. de 13_97).

Taxonomic notes:— Eperua bijuga differs from all other species by its 2-jugate leaves, non-falcate leaflets with flat margin and one pair of glands at the adaxial base, tubular corolla, puberulous inflorescences, and persistent bracteoles. Among the species with tubular corolla, E. bijuga shares some characteristics with E. glabriflora , E. grandiflora subsp. grandiflora , E. grandiflora subsp. ciliata , E. jenmanii , E. oleifera , and E. purpurea , such as a non-glabrous sheath and glabrous ovary. However, E. bijuga is distinguished by its falcate ovary (vs. oblong or oblong-obovate in the others). Eperua bijuga is most morphologically similar to E. glabriflora . Both species share 2-jugate leaves, non-falcate leaflets with two intramarginal veins, and a corolla of similar size and shape. However, E. bijuga differs by its puberulous to puberulent inflorescence, buds, sepals, and hypanthium (vs. glabrous in E. glabriflora ), and smaller and persistent bracteoles (vs. larger and caducous in E. glabriflora ).

Selected specimens:— BRAZIL. Amapá, Ferreira Gomes, Mangabeira , 29 May 2019, Rocha A.E.S. & Costa-Neto S.V. da 2165 ( MG). Macapá, braço do rio Macacoari , July 1982, Rabelo B.V. & Cardoso J.O. 1261 ( HAMAB, MG, NY, US). Porto Grande, Cupixi, Estrada Perimetral Norte , 15 December 1985, Rabelo B.V. et al. 3307 ( HAMAB, INPA, NY ). Tartarugarzinho, Rio Apurena , 22 July 1951, Fróes R. de L. & Black G.A. 27607 ( IAN, NY, R). Pará, Afuá , rio urucu, 14 November–04 December 1992, Maciel U.N. et al. 2147 ( MG). Ananindeua, vila Marituba, Igarapé Marituba , 03 May 1991, Almeida S.S. et al. 458 ( MG). Belém, Tapan „, beira da estrada, 02 May 1975, Oliveira E. 6291 (MG, RB); IPEAN. Reserva do Aurá. L.166–70-sn, 03 June 1968, Pires J.M. & Silva N.T. 11785 ( HUEFS, IAN, RB, MFS). Breves, Araurá. Rio Maratana, afluente do rio aramé ( Ilha Breves ), margem inundada, 01 December 1922, Ducke W.A. s.n. RB16927 ( P, RB, U). Melgaço, Floresta Nacional de Caxiuan „, Ima 6, rio Curuzinho, 1°72’25”S 51°43’11”W, 20 April 2004, Freitas M.A. de et al. 1093 ( INPA, MG, NY, RB ). Moju, Experimental Field Station of Embrapa Amazônia Oriental , PA-150, km 34, 2°10’50”S 48°0’0”W, 15 May 2008, Torke B.M. 432 ( IAN, RB). Mosqueiro, Rio Pará , 20 June 1943, Ducke W.A. 1260 ( IAN, F, K, MG, MO, NY, R, US); unknown locality, 13 October 1923, Ducke W.A. s.n. RB16928 ( RB, U). Muaná, Trajeto Monte Alegre / Santo André , 24 April 1982, Dantas M. & Silva N.T. da 1182 ( IAN). Portel, FLONA de Caxiuan „,margem do igarapé Caquajó , 1°57’00.0”S 51°35’00.0”W, 08 July 2007, Félix-da-Silva M.M. et al. 241 ( IAN, MG); regi„o do Anapú, Rio Tapacú , 10 May 1956, Fróes R. de L. 32776 ( IAN); regi„o do Anapú, Rio Maparauá , 05 August 1956, Fróes R. de L. 32938 ( IAN, MG). Salvaterra, Ilha do Marajó, Rio Paracauarí , margem do campo de pastagem do Sítio Caçador , 06 September 1969, Oliveira E. 4929 ( IAN); Marajó, margem direita do Rio Jubim, próximo da Rod. Salvaterra-Joanes , a 16 Km de Joanes , 24 April 1980, Rosa N.A. 3628 ( INPA, MG, NY ). Santa Isabel do Pará, Caraparú , 25 April 1977, Silva M.G. da 3391 ( MG). Soure, insula Marajó , 13 April 1927, Ducke W.A. s.n. RB20312 ( K, RB, U, US). Tailândia, Fazenda Borba Gato, near Rio Acará , 30 km W of Tomé-Açú-Paragominas road, approx. 30 km S of Tomé-Açú, 2°40’00.0”S 48°35’00.0”W, 08 November 1980, Daly D.C. et al. 889 ( INPA, IAN, K, MG, NY, US ). Tomé Açu, margem do rio Acará , 02 January 1978, Nascimento O.C. do 398 ( MG, NY, US). Rio de Janeiro (cultivated), Rio de Janeiro, Arboreto do Jardim Botânico do Rio de Janeiro, 09 August 1991, Fontella H. & Caruso J. 2770 ( RB). FRENCH GUIANA (cultivated?). unknown locality, undated, s.c. s.n. P03465139 ( P) .

Figures

FIGURE 10. Geographic distribution of Eperua bijuga, E. glabriflora var. glabriflora, and E. glabriflora var. gynopubescens.

FIGURE 17. Eperua bijuga: A. trunk base; B. trunk; C. bark of a younger specimen; D. bark of an older specimen; E. sap-wood and heartwood; F. leaves; G. fruits. Specimens, A–G: Fortes E.A. et al. 189. Photos, E.A. Fortes.

FIGURE 18. Eperua bijuga: A. fruiting branchlet; B. anther and part of the filament; C. puberulent to puberulous hypanthium and puberulous sheath; D. detail of a capitate stigma; E. glabrous stipe and ovary; F. adaxial petal. Specimens, A: Ferreira G.C. & Ribeiro B.G.S. 496, B–F: Fróes R. de L. 32988. Illustrated by Carlos Alvarez.