Memecylon multinode Jacq.
Creators: name: Stone, Robert Douglas
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Myrtales
Melastomataceae
Memecylon
Memecylon multinode

description: 7. Memecylon multinode Jacq. -F él. in Bull. Mus. Natl. Hist. Nat., B, Adansonia 7: 28. 1985.
Holotypus: MADAGASCAR. Reg. DIANA [Prov. Antsiranana]: forêt d’Analafondro, base du plateau de Sahafary, rive gauche du Rodo inférieur, 01.V.1966, fl. & fr., Service Forestier 24711 (P [P00062662]!; iso-: TE F [TE F000323]!).
Shrub, many-branched; branchlets slender, quadrangular when young, becoming terete with age; internodes 4– 6(–7) mm long, “aphyllous” nodes lacking (all nodes bearing normal leaves). Leaves coriaceous, opaque, bright green and shining on the upper surface, paler and dull below, minutely rugose on both surfaces when dry; petioles slender, 1.5–2 mm long; blades lanceolate to elliptic, 1.6 – 1.8(– 1.9) × 0.6 – 0.7 cm, cuneate at base, acute-cuspidate at apex; midnerve invisible on adaxial surface, slightly visible and not prominent abaxially; margin narrowly thickened, subrevolute. Cymules discrete, axillary, 1-flowered; peduncle 1– 4 mm long, often with an internode 1–3 mm long. Pedicels 1–2 mm long; floral buds ellipsoid-globose, corolla rounded; hypantho-calyx obconic, 2 × 2.5 mm, lobes scarcely pronounced; petals thickened on the abaxial side, suborbicular, 2.5 × 2.2 mm, claw short; anthers 1.2 mm long, anther sacs lateral; connective obtuse, moderately incurved by the median, elliptic gland; filaments 2.5 mm long; epigynous chamber deep, partitions joined in pairs to form V-shaped structures beneath the petal scars, each then joined to the center by a line; style 7 mm long. Fruits ellipsoidglobose, 6 × 5 mm; crown spreading, 1.5 mm long.
Distribution and ecology. – Extreme northeastern Madagascar (DIANA region), known only from the type collection.
Conservation status. – Memecylon multinode is known from a single location with an estimated AOO of 4 km ². The lower Irodo valley has been largely deforested since the type collection was made in 1966, and the species could not be found there during field-work in F ebruary 2008, suggesting that it may already be extinct or at least locally extirpated (R.D. Stone, pers. obs.). With additional field-work, it might be rediscovered in the nearby Réserve Spéciale d’Analamerana. Memecylon multinode is thus provisionally assessed as “Critically Endangered” [CR A2(c)+B2(iii)] in accordance with the IUCN Red List Categories and Criteria (IUCN, 2012).
Notes. – In the protologue, JACQUES- F ÉLIX (1985b) compared this species with Memecylon boinense, but it clearly belongs to Memecylon sect. Buxifolia, on account of its leaf apices acute-cuspidate, corolla rounded in bud, petals suborbicular, epigynous chamber with interstaminal partitions forming a V-shaped structure beneath each petal scar, and fruits ± ellipsoid. However, M. multinode lacks the “aphyllous” nodes characterizing most other species in this group (STONE, 2014). The numerous, short internodes and small leaves are also quite distinctive. It is most similar to M. minutifolium, which has even smaller leaves.
description: Published as part of Stone, Robert Douglas, 2022, Revised treatment of Memecylon section Buxifolia (Melastomataceae) in Madagascar, pp. 173-191 in Candollea 77 (2) on page 184, DOI: 10.15553/c2022v772a5, http://zenodo.org/record/7616620