Eperua obtusata R.S. Cowan (1975: 33)

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 : 73-75

13. Eperua obtusata R.S. Cowan (1975: 33)

( Figure 13 , 16b, c, e , 42 )

Type:— VENEZUELA. Amazonas: Capihuara, Rio Casiquiare, 3 October 1943, Williams L. 16183 (lolotype US [00001148]!).

Tree 10.0–20.0 m tall. Trunk, bark smooth, lenticellate. Stipules 7.3 × 2.3 mm, free, non-foliaceous, caducous. Leaves 2-jugate; petioles 2.6–4.5 cm long; rachis 3.4–5.3 cm long; petiolules 4.5–7.5 mm long; blades 8.0–13.0 × 4.0–5.9 cm, coriaceous, glabrous, pellucid-punctate, discolorous, equilateral, lower pair elliptic to oblong, upper pair elliptic, apex rounded to obtuse, base asymmetrical, lower pair base obtuse to cuneate, upper pair base cuneate, margin flat to slightly revolute, secondary venation with one intramarginal vein, main vein straight, prominent to depressed on the adaxial surface, tertiary veins conspicuous, areoles larger, plane. Inflorescences axillary or ramiflorous, raceme, erect, strigulose, brownish- yellow, 7.5–9.5 cm long; bracts not seen, caducous; bracteoles ca. 2.0 × 1.0–2.0 mm, ovate, strigulose to tomentose externally, brownish-yellow, caducous, attached to the lower portion of the pedicel; pedicel 8.0–10.0 mm long, 0.8–1.1 mm in diameter, not twisted, strigulose, brownish-yellow; buds 0.5 cm long, 0.2 cm in diameter, strigulose, brownish-yellow. Flowers: hypanthium 2.0–3.0 mm long, 3.3–4.6 mm in diameter, cup-shaped, equilateral, strigulose, brownish-yellow; sepal 1.6–2.0 × 0.4 cm, oblong to elliptic, unequal, the outer ones larger, apex gland present, strigulose, inner ones scarious marginally, brownish-yellow; adaxial petal 3.5–5.0 × 6.5 cm, flabellate, tubular, apex rounded, base attenuate, glabrous; petalodia 4.0–5.0 × 1.5–1.8 mm; stamens inserted, joined basally in a diadelphous sheath, dorsal one free, filaments 11.5–26.0 cm long, sheath inequilateral, 6.5–10.0 mm long, glabrous, anther 2.6–3.5 × 1.2–1.5 mm, rectangular; ovary 5.0 × 2.0 mm, obovate, sericeous, brownish-yellow, stipe 4.0 mm long, sericeous, style 3.4 cm long, stigma truncate. Legumes not seen.

Phenology:— Flowering in October.

Distribution— Casiquiare River region in Venezuela (Amazonas).

Habitat:— Tall campinarana and terra-firme forest, on sandy soil, from 106 to 306 m elev. Coomes & Gribb (1996) cited E. obtusata as one of the dominant species in the tall campinarana of La Esmeralda ( Venezuela).

Conservation status:— Categorized as Data Deficient (DD) according to the IUCN criteria ( IUCN 2012, IUCN Standards and Petitions Committee 2022) due to the lack of access to its collections.

Occurrence in protected areas:— Unknown.

Etymology:— Eperua obtusata and E. banaensis are the only species with leaflets with an obtuse apex, and the specific epithet obtusata relates to that characteristic.

Vernacular names:— Unknown.

Uses:— Unknown.

Taxonomic notes:— Eperua banaensis and E. obtusata are the only species in the genus with rounded, obtuse, acute to emarginate leaflet apex in the genus, whereas all other species have an attenuate, acuminate to caudate apex. They share 2-jugate leaves, short and erect inflorescence, tubular corolla, inserted stamens, and the same pattern of reproductive organ indumentum. Among the species with a tubular corolla, E. banaensis and E. obstusata are distinguished by the combination of glabrous sheaths and indumented ovaries ( Table 2 ). Differences between them are listed in the taxonomic notes of E. banaensis .

Specimens examined:— VENEZUELA. Amazonas, Casiaquire, Capihuara , 03 October 1943, Williams L . 16183 ( US). San Fernando de Atabapo, La Esmeralda, 5 Km North of village, near savanna Morichal , 106 m elev., 3°10’0’’S 65°33’0’’W, undated, Coomes D. 207 ( K) .

Figures

FIGURE 13. Geographic distribution of Eperua banaensis, E. jenmanii subsp. jenmanii, E. jenmanii subsp. sandwithii, and E. obtusata.

FIGURE 16. Eperua banaensis and Eperua obtusata: A. leaflets, upper leaflet obovate, E. banaensis; B. leaflets, upper pair elliptic to oblong, E. obtusata; C. intramarginal vein with one intramarginal vein, E. obtusata; D. intramarginal vein with one intramarginal vein, E. banaensis; E. pellucid-punctate blade, E. obtusata. Specimens, A, D: Collela M. et al. 1864; B, C, E: Coomes D. 207. Photos E.A. Fortes.

FIGURE 42. Eperua obtusata: flowering branchlet showing the 2-jugate leaves, and axillary inflorescence. Specimen, Williams L. 16183 (holotype). Illustrated by Carlos Alvarez.