Magnolia atlantida A.Vázquez

Vázquez-García, J. Antonio, Kelly, Daniel L., Mejía-Valdivieso, Darío A., Morales, Wilson, Dahua-Machoa, Alex, Vega-Rodríguez, Hermes, Peña, Alondra Salomé Ortega, Padilla-Lepe, Jesús & Muñiz-Castro, Miguel Á., 2022, Magnolia (Magnoliaceae) in Honduras: a synopsis with six new taxa, Phytotaxa 570 (2), pp. 109-149 : 112-115

Magnolia atlantida A.Vázquez , Recursos Forest. Occid. México 1: 92–94, f. 1.5.1. 2012. ( Figs. 2–3 )

Type:— HONDURAS. Depto. Atlántida : Slopes of Mt. Cangrejal , mountain slopes and coastal plains, vicinity of La Ceiba , 600 ft [183 m.], 06 Aug 1938 (immature fr), Yuncker 8845 (holotype: NY! ; isotypes: GH!, MO!) .

Trees (4–)6–17(–20) m high; twig internodes 0.7–2 × 0.3–1.1 cm, glabrous, green to yellowish, with elliptic lenticels; stipules adnate to the entire length of the petiole, glabrous. Leaves petiolate, petioles (2–)3–6.2 × 0.3–0.5 cm, glabrous, laminas 17–39 × 9–15 cm, ovate to oblanceolate, acute at the base and apex, glabrous, abaxially glossy, 8–11 secondary veins per side. Flowers not seen, inferred from scars, trimerous, peduncle 1.8–2 cm × 1.7–1.9 cm, glabrous, hypsophylls (inferred from scars) 1–2, sepals 3, petals 6, stamens (counted from staminal scars at the staminophore) ca. 305–310, gynoecium ovoid, glabrous, carpels 90–96, flattened at the stylar tip, stylar tips 1.2–1.3 cm long. Fruits (inferred from gynoecium) ovoid, expected to be larger than 10 cm long; seeds unknown.

Distribution, habitat and phenology:— Endemic to Honduras, a rare tree at 150–650 m in coastal plains and slopes ( Fig. 1 ; Table 2 ). The habitat of this species includes primary forests in the Department of Atlántida. Flowering February–March, fruiting August–September.

Etymology and ethnobotany:— Refering to the Atlántida Department where the type locality of is located. Known locally in Spanish as magnolia. No ethnobotanical information has been recorded.

Notes:— Magnolia atlantida belongs to M. section Talauma subsection Talauma ; it is unique in having the largest number of stamens (305–310) among species in this subsection. Magnolia cespedesii ( Triana & Planchon 1862: 23) Frodin & Govaerts (1996: 70) also has a large number of stamens (250–275), but M. atlantida differs in having a smaller number of carpels (90–96 vs. 122–137). It has been misidentified as Talauma mexicana ( Magnolia mexicana ) and as M. sambuensis ( Pittier 1918: 105) Frodin & Govaerts (1996: 72) . Standley used an unpublished name (no date) for this species, and in 1990 Chin Sung Sang noted that it was a nomen nudum. Flowering and fruiting material are still needed to complement its description.

Conservation status:— Critically endangered (CR), according to the IUCN criterion B1ab(iii) ( IUCN 2012). Extent of occurrence (EOO) <100 km 2 and area of occupancy is 8 km 2; it is known to exist only in Atlantida Department at two locations: Mt. Cangrejal in Pico Bonito and Nombre de Dios national parks. A continuing decline in extent area and habitat quality has been observed. Its narrow distribution indicates that this species is facing an extremely high risk of extinction in the wild. It has been recently rediscovered, by Hermes Vega, at Parque Nacional Nombre de Dios, La Ceiba , Atlántida, close to the type locality. This species needs further exploration and urgent protection ( Table 1 ).

Additional specimens examined:— HONDURAS. Depto. Atlántida: Jutiapa, Parque Nacional de Dios, Cordillera Nombre de Dios, en la costa norte de Honduras, 624 m, 15°46’02.7”N, 86°36’24.1”W, 22 Oct 2021 (fr), Vega (digital images examined on the iNaturalist website: 166287443, 166287420, 166287459, 166287377).

Figures

FIGURE 1. Geographic distribution of Honduran Magnoliaceae.

FIGURE 2. Magnolia atlantida. A. Leaf, adaxial side. B. Mature gynoecium (the two from Yuncker et al. 8845, NY and F, respectively). Photographs:A by V. Shalisko, 2014, and B by J. A. Vázquez-García, 2017.

FIGURE 3. Magnolia atlantida. A. Developing fruit. B. Dehiscing fruit, with seeds still attached. C–D, vegetative branches with leaves. Photographs by Hermes Vega.

Tables

TABLE 2 Elevation ranges of Honduran Magnolia species.

Species	Elevation (m asl)
	0 - 200	201 - 400	401 - 600	601 - 800	801 - 1000	1001 - 1200	1201 - 1400	1401 - 1600	1601 - 1800	1801 - 2000	2001 - 2200	2201 - 2400
Magnolia sect. Talauma
M. atlantida M. cochranei	X	X	X	X			X	X	X	X
Magnolia sect. Magnolia
M. yoroconte M. sororum subsp. oligocarpa M. pastorcortesii M. hondurensis M. celaquensis M. picopijolensis M. cusucoensis M. sororum subsp. sororum M. darioi				X	X	X X	X X X	X X X X X	X X X X	X X	X X	X