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| Chamaecrista almanegra A.M.Trujillo, Londoño-Ech. & Idárraga, in Trujillo-López, Londoño-Echeverri & Idárraga-Piedrahíta, 2022. |
Abstract:
A new species of Chamaecrista sect. Apoucouita (Caesalpinioideae, Fabaceae) from the Middle Magdalena Valley and Bajo Cauca region in the department of Antioquia, Colombia is described and illustrated. Chamaecrista almanegra differs from morphologically similar species mainly by its leaves with 4 to 6 pairs of leaflets (up to 8 pairs only in juvenile individuals), these remarkably falcate, wider in the acroscopic half and with secondary veins joined by an intramarginal vein at the proximal portion of the leaflet and becoming brochidodromous toward the distal portion, as well as anthers with indumentum on the entire surface. Notes about the geographical distribution, habitat and conservation status of the new species are presented, along with a key for the species of Chamaecrista sect. Apoucouita known for Colombia. This constitutes the first record of the section for the Inter Andean Valleys of the northern Andes, thus expanding its distributional range and potentially generating new hypotheses for future systematic and biogeographic studies in the genus.
Keywords: Biodiversity, Cassieae, endangered species, endemic species, Leguminosae, timber species
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| Chamaecrista almanegra. A. Branch. B. Vegetative buds, stipule, petiole nectaries and abscission scar of leaflet. C. Inflorescence. D. Inflorescence nectaries. E. Sepal. F. Corolla. G. Androecium and gynoecium. H. Anther. I. Pistil. J. Fruit. K. Seed. [A from the holotype; B–C from Londoño & Trujillo 294; D–I from Londoño & Trujillo 295; J–K from Trujillo & Londoño 112. Drawn by Diego Armando Zapata, HUA illustrator.] |
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| Chamaecrista almanegra. A. Branch. B. Young leaves. C. Floriferous branch. D. Floral buds. E. Corolla aestivation. F. Flower. G. Fruit. [A–B, D–E from Londoño & Trujillo 294; C, F from Londoño & Trujillo 295; G from Trujillo & Londoño 112. Photos by A. M. Trujillo, edited by Ana Cristina Pareja, HUA illustrator.] |
Chamaecrista almanegra A.M.Trujillo, Londoño-Ech. & Idárraga, sp. nov.
Diagnosis: Chamaecrista almanegra differs from morphologically similar Chamaecrista hymenaeifolia (Benth.) H.S.Irwin & Barneby by its leaves with 4–6 (−8) pairs of leaflets (vs. 1–2 [−3] pairs of leaflets), petiolule 1.6–2.8 mm long (vs. 3–6 mm long), leaflets wider in the acroscopic half (vs. wider in the basiscopic half or occasionally the halves equal), concolorous (vs. paler dull below), secondary veins joined by an intramarginal vein in the proximal portion of the leaflet, becoming brochidodromous in the distal portion (vs. craspedodromous-brochidodromous throughout the leaflet), a strictly marginal vein absent (vs. present), and anthers 3.4–4.4 mm long (vs. 4–4.6 mm long).
Etymology.— The epithet “almanegra” refers to the vernacular name given to the species at the type locality. It means “black soul” and describes the tree’s blackish wood, which is considered to be valuable and of fine quality.
Ana María Trujillo-López, Yeison Londoño-Echeverri and Álvaro Idárraga-Piedrahíta. 2022. A New Arboreal Chamaecrista (Fabaceae) and First Record of the Section Apoucouita for the Inter Andean Valleys of Colombia. Brittonia. 74, 78–86. DOI: 10.1007/s12228-021-09696-3
Resumen: Se describe e ilustra una nueva especie de Chamaecrista sect. Apoucouita (Caesalpinioideae, Fabaceae) del Valle del Magdalena Medio y la región del Bajo Cauca en el departamento de Antioquia, Colombia. Chamaecrista almanegra se diferencia de las especies morfológicamente similares principalmente por sus hojas con 4 a 6 pares de foliolos (hasta 8 pares solo en individuos juveniles), éstos notablemente falcados, más anchos en la mitad acroscópica y con las venas secundarias unidas por una vena intramarginal en la porción proximal del foliolo, volviéndose broquidódromas hacia la porción distal, así como, por sus anteras con indumento en toda la superficie. Se presentan notas sobre la distribución geográfica, el hábitat y el estado de conservación de la nueva especie, acompañados por una clave para las especies conocidas de Chamaecrista sect. Apoucouita para Colombia. Este es el primer registro de la sección para los Valles Interandinos del norte de los Andes, ampliando su rango de distribución y generando nuevas hipótesis para futuros estudios en sistemática y biogeografía del género.
