Corresponding author: Solange Sotuyo (
Academic editor: C. Morden
A new legume species from a seasonally dry forest of the Western Río Balsas Depression, in the states of Guerrero and Michoacán, Mexico,
Una nueva especie de leguminosa de la Depresión Occidental del Río Balsas en los estados de Guerrero y Michoacán,
Sotuyo S, Contreras-Jiménez JL, Lewis GP (2017) A new species of
Species of
During a revision of
México, Michoacán. Cerca de la cortina de la presa El Infiernillo
Similar to
Small tree or shrub, 2–6 m tall, bark grey pruinose, exfoliating, young branches reddish grey pruinose. Leaves bipinnate, (7.5–) 10–20 (–22) cm long; stipules triangular-acuminate, caducous, 2–3 × 1.2–1.5 mm, margin with red stipitate glands, white hairy on both surfaces; petiole (2–) 3.0–6.5 (–7.3) cm long, pubescent or glabrescent when mature; rachis (3–) 5.0–14.5 (–15.7) cm long, indumentum similar to that of the petiole; pinnae (5–) 7–13 per leaf, (1.6–) 2–6 (–7.7) cm long, densely pubescent when young, glabrescent when mature; leaflets (3) 4–7 (–10) jugate, clustered on the upper half of the pinnae rachises, obovate, elliptic or oblong-elliptic (6–) 10–20 (–25) × (4–) 5–11 (–13) mm, base rounded, slightly oblique, margin entire and lacking glands, or with sunken black punctate glands that render the margin slightly crenulate, apex obtuse to rounded, pubescent or glabrescent at maturity. Inflorescence an erect or pendulous (the peduncles curved downwards), terminal or axillary raceme or panicle (with few branches near the base), (6–) 10–36 cm long, densely white pubescent, and with red glands; bracts ovate-caudate, caducous, (2.5–) 3.2–5.0 (–5.7) × (1–) 1.3–2.0 (–2.3) mm, margin with or without glands, densely white pubescent on both surfaces; pedicels slender, erect-patent, (6–) 7.5–11.0 (–16.5) mm long, articulated at or above the middle, densely white pubescent, sometimes twisted, so that the flowers are resupinate (although then presented with the median petal uppermost on the pendulous inflorescences). Calyx light yellow-ochre, densely pubescent, tube obliquely obconic, laterally compressed, (4.3–) 4.7–6.0 × (2.1–) 2.5–3.5 (–4) mm; adaxial sepals ovate to oblong-ovate, 5.5–7.0 × 2.5–4.1 mm, slightly concave, the lateral sepals oblong-ovate, 5.4–7.0 mm × 2.7–4.0 mm; abaxial sepal cymbiform, (5.7–) 6–7.2 (–7.4) × (3.6–) 3.8–5.0 mm, all sepals with an entire margin, glandular ciliate and with an acute apex, puberulent on adaxial surface; petals salmon-coloured, clawed; adaxial petal ovate, 5.2–7.5 × 3.5–5.5 mm, base cordate, margin entire, apex obtuse, rounded, with stipitate glands near the claw apex on the abaxial surface, pilose on the adaxial surface; claw 1.8–3.0 mm long, sigmoid curved, ciliate, pilose and glandular-stipitate on abaxial surface or glabrous and sparsely stipitate-glandular; lateral petals ovate, 5.6–7.5 (–8) × 4.2–6 (–6.5) mm, base obtuse, margin glandular ciliate up to ⅕ of its length, apex rounded or obtuse, stipitate-glandular on abaxial surface, the abaxial petals ovate (6–) 6.5–8.5 × 3.7–5.5 (–5.7) mm, base oblique, margin entire, glandular ciliate from the base up to ⅕ of their length, apex obtuse, the claw ciliate and pilose on its abaxial surface; stamens curved, filaments (6.5–) 7.5–9.5 (–10) mm long, flattened at the base, densely villous to ¾ of their length, the upper third with lime green stipitate glands; anthers oblong-elliptic, (1.2–) 1.3–1.8 × (0.8–) 0.9–1.2 (–1.3) mm, erect at anthesis; ovary (1.7–) 2–3 (–3.5) mm long borne on a stipe 0.5 mm long, densely sericeous and with green cupuliform glands (or these absent); style curved, of different lengths in individual flowers, either short, 2.5–3.5 mm long, or well developed and 4.0–6.5 mm long, pilose for ½ of its length from base; stigma porate laterally; ovules 2 (–3) per ovary. Legume falcate, (3.7–) 4.3–5.7 × 1.1–1.7 cm, chartaceous, brown-yellow to vinaceous, densely to sparsely pubescent or glabrous when mature, with red stipitate glands or these glands absent, sutures densely pubescent, elastically dehiscent; seeds 1–2 (–3) per fruit, obovate, (8.6–) 9.5–10.5 (–11) × 7.5–9.6 × (1.7–) 1.9–2.2 (–2.4) mm, olive-brown, nitid.
Seasonally dry tropical forest on rocky slopes, locally common in secondary vegetation along roads, on alluvial soils near seasonal or permanent streams.
Known only from the western region of the Río Balsas Depression, in the states of Guerrero and Michoacán. Flowering from February to April and in fruit from February to May.
Selected specimens examined. MÉXICO.
We recommend that
The species epithet is dedicated to Fernando Guevara Fefer who recently passed away. Friend, botany teacher and researcher at the
Field and laboratory observations reveal two kinds of flower, with either a short or long pistil, as also observed in
1 | Shrubs or herbaceous plants; leaflets without black glands along margin; flowers deflexed; glandular stamen filaments curved, twice the length of the petals; legume 4.7–7.1 cm long; Sierra Madre del Sur, Guerrero and Oaxaca, 1400–2000 m elevation |
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– | Trees; leaflets with black glands along margin; flowers reflexed; stamen filaments falcate or curved, equalling the length of the petals; legume 3–6 cm long; seasonally dry forest of the Río Balsas Depression, 100–1200 m elevation |
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2 | Leaves with 3–5 pairs per pinnae, leaflets 2–6 pairs per pinna; inflorescence a raceme, on a short woody brachyblast |
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– | Leaves with 7–13 pairs per pinnae, leaflets 4–11 pairs per pinna; inflorescence a terminal or axillary raceme or panicle, peduncles branched near base |
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3 | Leaflets 2–3 pairs per pinna; pedicels 6.5–12.5 mm long, pubescent; eastern region of Río Balsas Depression (Ozomatlán, Guerrero) |
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– | Leaflets 4–6 pairs per pinna; pedicels c. 7 mm long, densely stipitate-glandular; Valle de Tehuacán-Cuicatlán (Puebla and Oaxaca) |
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4 | Pedicels articulated below the middle; petals yellow; leaflets oblong-elliptic |
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– | Pedicels articulated at or above the middle; petals pink, red or scarlet; leaflets ovate or oblong |
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5 | Fruit with red cupuliform glands or these absent; standard petal red or salmon coloured, stamen filaments pubescent on basal ½ to ¾, sometimes stipitate-glandular; western part of Río Balsas Depression (Guerrero and Michoacán) |
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– | Fruit with green pixie-cup (or doughnut-shaped) glands; standard petal pale pink with a red blotch at the lamina base on the inner surface; stamen filaments with green glands; western Río Balsas Depression (Guerrero, Oaxaca and Puebla) |
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6 | Leaflets obovate to elliptic, inserted along the pinna rachis; bracts erect or incurved; stamen filaments 13–15 mm long; legume with red cupuliform glands; seasonally dry forest in Guerrero and Michoacán |
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– | Leaflets oblong-elliptic, inserted on the upper half of the pinna rachis; bracts ovate-caudate; stamen filaments 6.5–10 mm long; legume with or without red cupuliform glands; Infiernillo region in the Río Balsas Depression (Guerrero and Michoacán) |
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We thank Albino Luna for the botanical illustration and Martha Martínez Gordillo for the Latin diagnosis. We thank the editor and two anonymous reviewers for their constructive comments, which helped us to improve the manuscript.