Mezilaurus introrsa F.M. Alves & van der Werff, 2012

Alves, Flávio M., Werff, Henk Van Der & Souza, Vinicius C., 2012, Mezilaurus introrsa (Lauraceae), a new species from Colombia, Phytotaxa 48 (1), pp. 29-32 : 30

Mezilaurus introrsa F.M. Alves & van der Werff , sp. nov. ( Fig. 1 )

A Mezilauro subcordata foliis basi attenuatis, floribus ovariisque glabris differt, a Mezilauro itauba tepalis dimidium florum attingentibus, staminibus haud exsertis et antheris extrorsis recedit.

Type:— COLOMBIA. Vaupés: Estación Ecológica Caparú within 3 km of the north bank of Lago Taraira , 1°00’S, 69°49'W, 200 m, 4 August 1988, fl., S . Defler 219 (Holotype MO 6216882 !) .

Trees to 30 m; twigs with lenticels, sparsely appressed pubescent distally, with conspicuous leaf scars; terminal buds 4–5.5 mm, appressed pubescent. Leaves alternate, crowded at branch tips; petiole flat to weakly canaliculate, 14–24 mm long, 10–15% of leaves, puberulous, the base dilated; blade elliptic, 11–17 × 4–6 cm, 2.2–2.7 times longer than wide, chartaceous, concolorous, base attenuate to decurrent, apex bluntly acute, glabrous, the margin plane, adaxial venation immersed, abaxial prominent, glandular dots visible on abaxial surface; lateral veins 9–14 pairs, arching upwards near the margin, the distal ones weakly loop-connected. Inflorescences paniculate, 3.9–7 cm long, shorter than the leaves, sparsely appressed pubescent; flowers clustered at the apex of lateral branches, peduncle 1.5–3.5 cm long, bracteoles deciduous; pedicel 0.5–1 mm long, reaching 1/3–1/2 of the length of the flower. Flowers depressed globose, 2–2.25 mm diam. × 1.5–1.75 mm long, glabrous externally and puberulous internally; hypanthium 0.75 mm long; tepals erect, equal to sub equal, 1–1.5 wide × 1–1.5 mm long, as long as or longer than the receptacle; stamens included, ca. 1 × 1 mm, free, without glands, anthers glabrous, 2–locular, locelli introrse to apical-introrse, filaments as long as the anthers but much wider, tomentose; staminodia absent or only 1 present, 0.5 mm long, representing the fourth androecial whorl, apex pyramidal, pubescent; gynoecium 1.8 mm long, glabrous, the ovary globose, the style 1 / 3 – 1 / 2 length of the gynoecium, stigma flat. Fruit a drupe, ellipsoid, to 30 × 13 mm, glabrous; pedicel ca. 3 mm, glabrous; cupule small, plate-like, ca. 5.5 mm diam., glabrous.

Paratype:— COLOMBIA. Vaupés: Estación Ecológica Caparú within 3 km of the north bank of Lago Taraira , 1°00’S, 69°49'W, 200 m, 22 September 1989, fr., S . Defler 220 ( MO!) .

Distribution:— Mezilaurus introrsa is only known from the Ecological Station of Caparú in southeastern Colombia, Vaupés state, where it occurs in seasonally inundated forest, locally called “igapó”, at 200 m a.s.l.

Conservation Status:— The species is known from two collections from the same tree in the southeast of Colombia, state of Vaupés. The area is botanically poorly explored. Therefore, the species can be assessed using the IUCN Categories and Criteria (IUCN 2001) as Data Deficient (DD).

Phenology:— Flowers in August and fruits in September.

Etymology:— The epithet is based on the introrse stamens.

Figures

FIGURE 1. Mezilaurus introrsa. A. Habit, flowering branch. B. Flower. C. Stamen. D. Pistil. (drawn from the holotype). E. Mature fruit (drawn from the paratype).