Macrolobium longistipitatum A. M. Trujillo & Londono-Ech. 2023, sp. nov.

Macrolobium longistipitatum A.M.Trujillo & Londoño-Ech., sp. nov. (Figs. 4 & 5) Type:— COLOMBIA. Antioquia. Mun. San Luis: Quebrada “La Cristalina”, Sector NE, 760–770 m, 6°00ʹ00ʹʹN, 74°45ʹ00ʹʹW, 22 March 1987 (fl), J. G. Ramírez & D. Cárdenas 708 (holotype: JAUM-19258!, isotypes: HUA-75151!, COL-323419 [digital image!]). Diagnosis:— Macrolobium longistipitatum differs from all congeners by the following morphological combination: stipules caducous, leaves with numerous leaflets (17–39 pairs) and shorter distance between leaflets (2–5.8 mm long), leaflet blades slightly rounded and occasionally retuse apically, with veins prominent up the fourth-order on both surfaces, secondary veins closely parallel; longer and (sub-) terminal inflorescences (7.5–16.7 cm long including peduncle), shorter peduncle (1.2–3.3 mm long), shorter flowering pedicel (0.7–1.3 mm long), bracteoles glabrous, single petal long-unguiculate, hypanthium cupular with longer stipe (1.7–3.9 mm long stipitate), sepals 4, elliptic to oblong, petalodia 2, staminodes 2, filaments of fertile stamens sparsely villose at base and ovary glabrous. Trees 12–40 m tall, cataphylls 0.4–3.8 × 0.9–3.8 mm, broadly ovate, rounded and obtuse apically, occasionally ripped and apparently emarginate, abaxially puberulous at base, sparsely puberulous towards apex, adaxially glabrous and papillose, papillae conspicuously orange, caducous, margin entire; branchlets striate, villose, glabrescent, indumentum shiny brownish red, whitish with age, branchlet surface dark red, smooth waxy with age, bearing 9–12 leaves; stipules (3.8–) 8.9–14.8 × 1.2–3.5 mm, lanceolate, obtuse and rounded at the apex, sparsely puberulous abaxially, otherwise glabrous, papillose and sparsely smooth waxy adaxially, caducous, veins parallel basally becoming reticulate apically, raised abaxially, flat adaxially, margin entire, papillose. Leaves pinnate, with 17–39 pairs of leaflets, distichous, indumentum shiny brownish red but whitish with age throughout leaves; petiole 1.7–5.2 mm long, slightly canaliculate adaxially, villose; rachis 6.0– 20.2 cm long, winged adaxially, villose, wings ca. 0.5 mm high, revolute when mature (flat when young), villose, distance between leaflets 2–5.8 mm long; leaflet blades 5.4–23.5 × 2.2–6.6 mm, oblong, lanceolate or ovate, basally obtuse and rounded at basiscopic half, truncate to cuneate and auriculate at acroscopic half, apically obtuse and slightly rounded, occasionally retuse, villose at very base and pilosulose on midvein in both surfaces, surfaces otherwise glabrous, concolorous; veins up to fourth-order raised on both surfaces, secondary veins numerous, not clearly differentiable from intersecondary veins, closely parallel, mainly brochidodromous, some veins cladodromous, intersecondary veins present, tertiary veins ramified, margin entire, ciliate. Inflorescences as racemes 7.5–16.7 cm long (axis including peduncle), (sub-) terminal, glabrous, surface smooth waxy basally, 1.2–3.3 mm long pedunculate, 36–75-flowered; bracts 6.9–8.6 × 2.5–3.6 mm, elliptic, acute and straight apically, glabrous and sparsely smooth waxy on both surfaces, early caducous, margin entire; pedicel 0.7–1.3 × 0.8–1.1 mm (fruiting pedicels 5.1–8.2 mm long), glabrous, bracteoles 5.6–8 × 1.7–2.9 mm, oblong, obtuse and rounded apically, glabrous and sparsely smooth waxy on both surfaces, longitudinally ridged at medial abaxial surface, opening completely in both sides of the flower but belatedly on the adaxial side, caducous, margin entire; hypanthium 4.5–5.9 × 1.1–2.1 mm, (including stipe), 1.7–3.9 mm long stipitate, cupular, zygomorphic, glabrous, calyx 4-merous, sepals 6.5–9.8 × 2.2–3.9 mm, elliptic to oblong, obtuse and rounded to straight apically, glabrous and papillose in both surfaces, slightly unequal in shape and size, margin entire; single petal 15.2–15.8 × 6–6.1 mm (including claw), obovate, obtuse and rounded apically, 6.3–6.8 mm long unguiculate, villose on midvein adaxially, otherwise glabrous and papillose, occasionally smooth waxy at abaxial surface, margin entire, undulate; petalodia 2, 2.3–6.6 × 0.6–1.9 mm, lanceolate, obovate to oblong, acute and straight apically, glabrous and papillose in both surfaces, borne at each lateral side of single petal; filaments 21.1–27.2 mm long, flattened adaxially, sparsely villose, anthers 1.7–1.8 × 0.7–0.9 mm, ellipsoid, very sparsely villose, papillose; staminodes 2, 0.7–1.1 × 0.2–0.4 mm, ovate to lanceolate, acute and straight to rounded apically, glabrous in both surfaces, alternate with stamens (i.e., at each lateral side of central stamen); gynophore 2.6–4 mm long, glabrous, inserted near the apex of the adaxial wall of the hypanthium, ovary 4.1–4.9 × 1.3–1.8 mm, oblong, glabrous, 3-ovulate, style 20.9–26.6 mm long (including stigma), glabrous, stigma papillose. Fruits 14.6–18 × 5.3–6.7 cm (including stipe), 0.6–0.7 cm long stipitate, oblanceolate to obovate, obtuse and rounded basally, obtuse and obliquely truncate apically, glabrous, sparsely dark-punctate, dehiscent, 2–3 seeds per fruit. Seeds 2.8–3.4 × 2.2–2.9 cm, (nearly) orbiculate, glabrous, dark brown, surface venulose. Distribution and habitat:— Macrolobium longistipitatum is endemic to central Colombia, where occurs in the limits between Andes and Magdalena Valley biogeographical regions at the eastern slopes of the Central Cordillera. It has been collected in the department of Antioquia, on the municipalities of Maceo and San Luis. Macrolobium longistipitatum inhabits lowlands rainforest, at elevations between 570 and 970 m, under equatorial rainforest climate (Af) according the Köppen-Geiger climate classification (Kottek et al. 2006) (Fig. 3). Phenology:— Flowering in March and August and fruiting in February, March, November and December. Etymology:— The epithet longistipitatum is derived of the Latin “longus” (long) and “stipitatum” (that has stipe), indicating that this species has a hypanthium long-stipitate, an unique feature for species with pinnate leaves within M. sect. Macrolobium. Conservation status:— Macrolobium longistipitatum has an area of occupancy (AOO) of 12 km 2, an extent of occurrence (EOO) of 336 km 2, and has three known subpopulations. All subpopulations occur outside of protected areas and are located less than 10 km from an urban center. The species is found in very small and fragmented forest patches (