Magnolia emilceana Archila, Tribouillier & A.Vázquez, 2024

Archila, Fredy, Navas, Erick Tribouillier, Alvarado, Otto, Pérez, Álvaro J., Shalisko, Viacheslav, Mendoza, Sandy & Vázquez-García, J. Antonio, 2024, Three new small-flowered Magnolia species (Magnolia sect. Magnolia, Magnoliaceae) from Guatemala, Phytotaxa 665 (2), pp. 129-144 : 130-135

Magnolia emilceana Archila, Tribouillier & A.Vázquez , sp. nov. ( Figs 1–3 )

Type:— GUATEMALA. Baja Verapaz: Municipio de Purulhá , 1450 m, 15°13’06”N 90°12’07”W, 7 Mar 2023, collected by Otto Alvarado, Archila & Tribouillier MG-115 (holotype: BIGU 84952 (fl, fr); isotype BIGU) .

Magnolia emilceana resembles Magnolia javieri A.Vázquez, Tribouill. & Archila in Vázquez-García et al. (2021: 60) and Magnolia archilana A.Vázquez, Tribouill. & Véliz in Vázquez-Garcia et al. (2019: 222), but can be differentiated from the former by its bigger and wider obovate leaves (vs. smaller obovate leaves), apex obliquely obtuse-acute (vs. deeply emarginate), stamens 110–113 (vs. 80–82), carpels 83–85 (vs. 40–44), and erect fruit (vs. pendulous); from the latter by its mature glabrous leaves (vs. abaxially ferruginous trichomes on the veins), smaller flowers, green, linear-elliptic sepals (vs. white and lanceolate oblong), purple staminophore (vs. red), 110–113 stamens (vs. 73–76), 83–85 carpels (vs. 34–39) and smaller fruits (4.0–4.5 × 2.0– 2.5 cm vs. 7.0–7.5 × 3.4–3.6 cm) ( Table 1).

Tree 6 m tall, 25 cm dbh. Petiole subterete, 2.2–2.4 cm long, glabrous. Leaves widely obovate, 12.5–15.2 × 9.0– 10.2 cm, in juveniles with an orange pubescence abaxially and along the margin, in adults glabrous, apex obliquelyobtuse-acute, base rounded, margin entire, secondary veins 11–12 on each side of the midrib. Peduncle 3.0–3.3 × 0.45–0.47 cm, totally covered with reddish brown trichomes. Perule 1.6 cm long, glabrous. Flowers solitary, 8.2–8.9 cm in diam; bracts 2, petiolate, embracing, the outer spathulate and microscopically pubescent apically and along the central dorsal line, 4.0–4.2 × 3.3–3.5 cm, the inner sub-elliptic, glabrous, apex obtuse, 4.0–4.2 × 2.4–2.5 cm; sepals 3, green, linear elliptic, deeply concave, apex obtuse, the first one oblong with rounded apex, the others obovate-elliptic with obtuse apex, 4.0–4.2 × 1.3–1.5 cm; petals 6, white, arranged in 2 series of 3, the outer series narrowly obovate-spathulate, apex obtuse-acute, 4.4–4.6 × 2.1–2.3 cm, the inner series narrowly obovate-spathulate, apex obtuse-acute, 3.0–3.1 × 1.5–1.6 cm; staminophore purple, 0.8– 0.5 cm in diam; stamens 110–113, 0.8–1.0 × 0.1–0.15 cm; gynoecium ellipsoid, 3.0–3.2 × 1.1–1.3 cm, pale green, stigma persistent, short, with an apiculate apex and slightly recurved outwards; carpels 83–85, 1.7–1.9 × 0.7–0.8 cm. Fruit oblongoid, 4.0–4.5 × 2.0– 2.5 cm, glabrous, green; seeds 1–2 per carpel, covered with a salmon-coloured sarcotesta.

Etymology:— Named for Emilce Ochoa de Tribouillier, 52 years old, who lives in the department of Quetzaltenango Guatemala, in recognition of her support for the second author, in the collection and management of samples of Guatemalan trees.

Distribution, habitat and ecology:— Known thus far only from the type locality, a severely disturbed cloud forests remnant ( Fig. 4 ). Traditionally the area has been used for coffee, corn and bean cultivation and timber. The new species is sympatric with M. ottoi A.Vázquez, Tribouill. & Archila in Vázquez.García et. al. (2020:189) (M. sect. Talauma ) and co-occurs with Hedyosmum mexicanum ( Chloranthaceae ), Liquidambar styraciflua ( Altingiaceae ), Quercus purulhana ( Fagaceae ) and Persea donnell-smithii ( Lauraceae ).

Phenology:— Flowering March, fruiting June.

Conservation status:— Following an exhaustive field exploration, no additional plants were found. Based on the best available evidence, the area of occupancy (AOO) is estimated to be less than 4 km 2 in a single location, with fewer than 50 mature individuals believed to exist. In accordance with the IUCN guidelines (2024), this new species is assessed as critically endangered (CR B2ab(iii)) due to its exceptionally small, restricted population. In situ and ex situ propagation programs are urgently needed because this new species does not occur in the Guatemalan System of Protected Areas (SIGAP) ( CONAP 2011).

Additional specimens examined:— GUATEMALA. Baja Verapaz: Municipio de Purulhá , 1450 m, 15°13’06”N 90°12’07”W, 3 Jul 2020, collected by Otto Alvarado, Archila & Tribouillier MG-213 ( BIGU89742 ) ; ibid., Archila & Tribouillier MG-214 ( BIGU 89743 ) ; ibid., Archila & Tribouillier MG-216 ( BIGU 89739 ) ; ibid., Archila & Tribouillier MG-217 ( BIGU 89740 ) ; ibid., Archila & Tribouillier MG-218 ( BIGU 89741 ) ; ibid., Archila & Tribouillier MG-219 ( BIGU 89737 ) .

Figures

FIGURE 1. Holotype of Magnolia emilceana. Archila & Tribouillier MG-115 (BIGU).

FIGURE 2. Magnolia emilceana. A. Flower. B. Bracts. C. Leaves showing adaxial and abaxial side. From Archila & Tribouillier MG-115. Photographs by Fredy Archila.

FIGURE 3. Magnolia emilceana. A. Abaxial side of leaf. B. Adaxial side of leaf. C. Flower. From Archila & Tribouillier MG-115. Line draw by Sandy Mendoza.

FIGURE 4. Location of M. emilceana, M. harnpariphana and M. juliana in Alta and Baja Verapaz Departments.