Magnolia corquinensis A.Vázquez, S.Morales & H.Vega, 2024

Morales-Molina, Sobeida, Vega-Rodri ́ Guez, Hermes, Shalisko, Viacheslav, Alemán-Avilez, Maryury & Vázquez-García, J. Antonio, 2024, A new species, Magnolia corquinensis, and a new record of Magnolia quetzal (Magnoliaceae) for Honduras, Phytotaxa 642 (2), pp. 191-200 : 192-193

Magnolia corquinensis A.Vázquez, S.Morales & H.Vega , sp. nov. ( Figs 1–5 )

Type:— HONDURAS. Department of Copán: Corquín municipality, Aldea Joconales , Sitio Cerro Negro , 14°31’01.0”N, 88°51’04.3”W, 1546 m, 25 Oct 2022 (fl., fr.), Sobeida Morales & Hermes Vega 003 (holotype: TEFH; isotypes: BIGU, HEH, IBUG, EAP) .

Magnolia corquinensis shares with M. celaquensis the relatively narrow leaves and pubescence on spathaceous bracts and peduncular internodes, but it differs from the latter in slightly undulate leaf blades vs. straight; more numerous lateral veins per side (14 vs. 12–13); shorter distalmost peduncular internode (2.5–3.0 vs. 3.3–3.9); gynoecium ovoid vs. narrowly ellipsoid; more numerous carpels 27–49 vs. 20–25; stamens purple at the base and the tip of the anther vs. only at the base; sepals broadly obovate vs. spathulate; sepals greyish green and pale brownish below vs. creamy white; petals obovate and slightly cochleate vs. broadly obovate, deeply cochleate; fruits ellipsoid to oblongoid with brownish green to purplish pubescence, retaining the original colour at dehiscence vs. ovoid, glabrous, green, turning blackish at dehiscence; carpel beaking at dehiscence, falcate vs. not breaking?, curled. Magnolia corquinensis shares with M. montebelloensis a similar carpel number, but it differs from the latter in leaf blades slightly undulate vs. undulate more numerous lateral veins per side (14 vs. 11–12); less numerous spathaceous bracts (2 vs. 3); shorter distalmost peduncular internode (2.5–3.0 vs. 1.5–2.0); more numerous stamens (86–98 vs. 53–85); stamens purple at the base and the tip of the anther vs. only at the base; sepals broadly obovate vs. spathulate; sepals grayish with light green margins and abaxially pale brownish vs. greenish; fruits pubescent and pale yellowish green, keeping original colour at dehiscence vs. glabrous and turning black at dehiscence; seeds discoid vs. ovoid.

Trees 20–30 × 0.3–1.0 m with a straight trunk, buttress roots, warty bark, yellowish white wood; vegetative twig internodes 0.25–0.90(–1.50) × 0.25–0.55 cm, peruls 2.0–3.0 × 4.0–5.0 mm, yellowish green, pubescent. Leaves with stipules free from the petiole, 13–20 × 4.0–7.0 mm, brownish to reddish at maturity; petioles 22–30 × 2.5–4.0 mm without a stipular scar, stout, pubescent, canaliculate; leaf blades 16.4–21.5 × 5.4–5.9 cm, lanceolate to oblanceolate, with slightly undulate margins, densely hairy golden and glabrescent towards apex adaxially, glabrous abaxially, except for the midvein, which is adaxially sunken and abaxially prominent, secondary veins 14, adaxially inconspicuous, curved. Peduncles 2.5–3.0 × 0.4–0.6 cm, pubescent; floral buds 4.2–4.3 × 2.0– 2.1 cm, broadly ellipsoid, obtuse to acute apically, truncate basally; spathaceous bracts 2, 3.9–4.0 × 1.9–2.0 cm, broadly ellipsoid, densely covered with hairs, one red-yellowish, the other pale brown-yellowish. Flowers 12.0–15.0 cm in diameter, creamy white, fragrant, trimerous; sepals 3, 6.3–7.0 × 2.5–3.0 cm, strongly veined, obovate, cochleate, greyish on the upper side with a light green margins, pale brownish below; outer petals 3, 7.2–7.5 × 3.1–3.5 cm, inner petals 3, 5.0–5.8 × 1.9–2.5 cm, both outer and inner petals obovate and slightly cochleate, the upper third rounded and acuminated towards the apex, truncated base, creamy white; staminophores (staminal receptacles) 1.2–1.4 × 0.5–0.6 cm, subcylindrical, narrow towards the apex, dark-purple; stamens 86–91(–98), 1.6–1.8 cm long, glabrous, white, purple-magenta at the base and apex, the connective extended; gynoecia 1.8 × 1.2 cm, ovoid, white at base; stigma yellow and orange, strongly curled; carpels 27–30(–49), brownish green, pubescent. Fruits 5.3–6.7 × 2.4–3.4 cm, ellipsoid to oblongoid, follicles 1.2–2.5 × 0.5–1.0 cm, broadly open; beaks curved, brownish green to purplish, keeping original colour at dehiscence; seeds 1.1–1.2 × 0.9–1.0, flattened, disk-like, red shiny, 1 seed per follicle.

Distribution and habitat:—Known only from two localities in the Montaña de Celaque National Park and vicinity ( Fig. 6 ) in mixed tropical cloud forests including Quercus cortesii Liebmann (1854: 175) , Nectandra Roll. in Rottbøll (1778: 279), Persea Miller (1754 : without page), Brunellia mexicana Standley (1927a: 166) , Myrsine coriacea ( Swartz 1788: 32) R.Br. in Roemer & Schultes (1819: 511), Liquidambar styraciflua Linnaeus (1753: 999) , Pinus tecunumanii F.Schwerdt f. in Eguiluz Piedra & Perry (1983: 4), Pinus maximinoi Moore (1966: 8) , Pourouma aspera Trécul (1847: 102) , Saurauia Willdenow (1801: 407) , Clethra Linnaeus (1753: 396) , Inga Miller (1754 : without page), Vismia Vandelli (1788: 51) , at 1556–2277 m. Flowering April–October, fruiting April–October.

Eponymy and ethnobotany:—Dedicated to the municipality of Corquín. The meaning of corquín (Toltec) is a land between rivers, Julalgua and Aruco.

Conservation status:—Due to its narrow distribution and observed small overall population size of 14 known mature individuals in two localities, this species should be considered critically endangered (IUCN criteria D). Extent of occurrence (EOO) <100 km 2 and area of occupancy (AOO) in two known localities is 8 km 2. One known localities is in the core zone of the protected area Montaña de Celaque National Park, but the type locality is outside the protected area.

Additional specimen examined:— HONDURAS. Department of Lempira: Gracias municipality, core zone of the Montaña de Celaque National Park, Campamento Don Tomás, 14°32’42.0”N, 88°39’56.7”W, 2277 m, 10 May 2023 (fl. & fr.), Vega et al. 2563 (TEFH, EAP).

Figures

FIGURE 1. Magnolia corquinensis. Flower at female phase (above); sepals and felty peduncles (below). Photographs: by H. Vega.

FIGURE 2. Magnolia corquinensis. A. Tree. B. Habitat. C. Trunk bark. D. Leaves. E. Leaves abaxially glaucous. F.Abaxial midvein base with pubescence. G.Abaxial midvein losing pubescence towards the apex. H. Internodes and leaf stipules. I. Stipules adnate to the petiole. J. Flower bud with spathaceous bract and early axillary leaf buds. Photographs A–C, H & J by H. Vega; D–G & I by S. Morales.

FIGURE 3. Magnolia corquinensis. A. Flower. B. Gynoecium with stamens and carpels. C. Detail of the veined sepal. D. Fruit with winered staminophore visible. E. Fruit with pubescent peduncle. F & G. Fruit, red shiny flattened seeds disk-like and follicle beaks curved. H. Fruit after dehiscence. I. Carpels removed to show morphological variability. Photographs A–C & E by H. Vega; D & F–I by S. Morales.

FIGURE 4. Comparison between Magnolia corquinensis A1–A3, M. celaquensis B1–B3 and M. montebelloensis C1–C3. Photographs A1–A2, B1–B2 by S. Morales; A3, B3 by H. Vega; C1–C3 by A. Vázquez.

FIGURE 5. Comparison between Magnolia corquinensis A4–A6, M. celaquensis B4–B6 and M. montebelloensis C4–C6. Photographs A4–A6, B4–B6 by S. Morales; C4–C6 by A. Vázquez.

FIGURE 6. Geographic distribution of Magnoliaceae (M. corquinensis, M. celaquensis and M. quetzal) in Corquín, Copán, Honduras.