Eperua venosa R.S. Cowan. (1958: 147)

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 : 95

19. Eperua venosa R.S. Cowan. (1958: 147)

( Figures 11 , 54 , 55 )

Type: — VENEZUELA. Bolívar: Angell Falls, undated, Kunhardt H . R . Jr. 20 (holotype NY [00004386]!) .

Tree 10.0–30.0 m tall. Trunk 60.0 cm in diameter, bark not seen. Stipules 3.0–4.3 × 2.0– 3.7 mm, joined, non-foliaceous, caducous, caducous. Leaves 1–2(–3)-jugate; petioles 1.3–3.4 cm long; rachis 2.4–5.1 cm long; petiolules 6.5–9.4 mm long; blades 6.6–21.0 × 3.3–9.3 cm, coriaceous, glabrous, pellucid-punctate, each areole has at least one conspicuous dot, not discolorous, equilateral to inequilateral, lower pair elliptic, slightly falcate, apex acuminate, base symmetrical to asymmetrical, lower pair base obtuse, upper pair base obtuse to cuneate, margin flat, secondary venation with one intramarginal vein very close to the margin, main vein curved to straight, prominent to depressed on the adaxial surface, tertiary veins very conspicuous, areoles larger, plane. Inflorescences terminal or axillary, panicle, main axis pendulous, lateral racemes erect, main axis puberulent to strigulose, lateral racemes strigose, pubescent to tomentulose, grayish-white, 145.0–162.0 cm long, lateral racemes 2.0– 5.2 cm long, alternate and spirally arranged; bracts not seen; bracteoles 4.1–5.8 × 3.8–5.1 mm, ovate to oblate, cucullate, apex gland absent, strigose externally, grayish-white, caducous, attached to the middle to high portion; pedicel 7.0–15.0 mm long, 2.5–7.6 mm in diameter, not twisted?, pubescent, strigose to tomentose, grayish-white; buds 2.0 cm long, 1.0 cm in diameter, pubescent to tomentose, grayish-white. Flowers: hypanthium 6.8–11.3 mm long, 4.2–6.5 mm in diameter, tubular to cup-shaped, equilateral, pubescent, strigose to tomentose, grayish-white; sepal 1.6–2.2 × 0.6–2.2 cm, elliptic to oblong, unequal, the outer ones larger, cucullate, apex gland absent, green with purple spots, pubescent, strigose to tomentose, scarious marginally, grayish-white; adaxial petal 2.5–3.4 × 4.7–6.0 cm, oblate, non-tubular, apex rounded, base attenuate, gibbous, deep-rose, sericeous at the base, glabrous in other parts, pellucid-punctate; petalodia 0.4–0.8 × 0.5–0.8 mm; stamens exserted, joined basally in a diadelphous sheath, dorsal one free sheath equilateral, 6.7–10.0 mm long, sheath sericeous to tomentose, free filaments glabrous, reddish-white, anthers 4.0–9.0 × 1.5–1.9 mm, rectangular; ovary 7.3– 10.0 × 3.2–4.9 mm, oblanceolate, densely sericeous, reddish-white, stipe 3.5–7.0 mm long, tomentose to sericeous, style length not seen, stigma capitate to bilobate. Legumes oblanceolate-falcate, puberulous (young fruit). Seeds not seen.

Phenology:— Flowering in August and September; fruiting in February.

Distribution:— Endemic to Venezuela (Bolívar), known only in the region of Gran Sabana.

Habitat:— Forests, being frequent in forest borders (Maguire B. et al. 53597), it is also found bordering savanna (Steyermark J.A. 115541), from 87 to 1160 m elev.

Conservation status:— Categorized as Vulnerable (VU) according to the IUCN criteria ( IUCN 2012, IUCN Standards and Petitions Committee 2022). The extent of estimated occurrence for the species is 6,325.304 km 2 and the estimated area of occupancy is 16.000 km 2.

Occurrence in protected areas:— Parque Nacional Canaima ( Venezuela, Bolívar).

Etymology:— The specific epithet relates to its very conspicuous tertiary veins on the adaxial blade surface.

Vernacular names:— Unknown.

Uses:— Unknown.

Taxonomic notes:— Eperua venosa is the only species in the genus with basally sericeous petals. It is morphologically similar to E. leucantha and E. falcata , with which it shares joined stipules, secondary venation with one intramarginal vein very close to the margin, long and pendulous inflorescences, non-tubular corolla, exserted stamens joined in a diadelphous sheath, and sericeous ovary ( Table 4 ). Besides that, E. venosa shares non-white petals with E. falcata , patent to erect lateral racemes and sericeous sheath with Eperua leucantha . However apart from the petal indumentum, Eperua venosa differs from E. falcata and E. leucantha by other characteristics that are listed in their taxonomic notes.

Selected specimens:— VENEZUELA. Bolívar, Gran Sabana, Angel Falls , undated, Kunhardt H . R . 20 ( NY), 7 kms al norte de la Misión de Santa Teresita de Kavanayén, 1160 m elev., 20 February 1978, Steyermark J . A . 115541 ( F). Rio Uiri-yuk, El Foco, alto Río Cuyuni , 30 August 1962, Maguire B . et al. 53514 ( NY, US). Triana Savanna, cerro Pitón, cordillera Epicara , rio Chicanán , 05 September 1962, Maguire B . et al. 53597 (RB, U, US).

Figures

FIGURE 11. Geographic distribution of Eperua falcata, E. leucantha, and E. venosa.

FIGURE 54. Eperuavenosa:A.joined stipules;B.leaflet baseshowing the tertiary veinsprominent on the adaxial surface;C.intramarginal vein, abaxial side; D. pellucid-punctate leaflet blade; E. lateral raceme; F. detail of the indumentum of the inflorescence main axis; G. flower showing the sheath, adaxial petal and sepal (some sepals were removed); H. adaxial petal (bent); I. detail of the indumentum at the base of the petal; K. sheath and ovary. Specimens, A–F, J, K: Maguire B. et al. 53597; G–I: Kunhardt H.R. Jr. 20 (holotype). Photos, E.A. Fortes.

FIGURE 55. Eperua venosa: bijugate leaf and part of the inflorescence. Specimen, Kunhardt H.R. Jr. 20 (holotype). Illustrated by Carlos Alvarez.