Memecylon fofifa R.D. Stone, 2020

Stone, Robert Douglas, 2020, New species of Memecylon (Melastomataceae) from Madagascar: treasures of the TEF Herbarium, Candollea 75 (2), pp. 219-239 : 225-227

Memecylon fofifa R.D. Stone , sp. nov. ( Fig. 4 ).

Holotypus: MADAGASCAR. Reg. Atsinanana [Prov. Toamasina]: Fénérive-Est, Tampolo , I.1986, fl. & y.fr., Service Forestier 32781 ( TEF!).

Affinis Memecylon cardiophyllo Cogn. sed lamina foliari supra nitida subtus obscura (non utrinque obscura), nervatione supra valde impressa plusminusve bullata (non nervatione sat inconspicua), pedunculis filiformibus 6–15(–24) mm (non 3–7 mm) longis, pedicellis longioribus 3–5 mm longis atque petalis minoribus c. 2 × 1 mm (non c. 3 × 1.8 mm) differt.

Evergreen shrub or small tree to 5 m high; young branchlets blackish alate-crisped, the wings soon excoriating and the older branchlets subquadrangular to terete with bark grayish brown; nodes densely bristly (bristles up to 3 mm long); internodes 1.4–3.7(–6.4) cm long. Leaves subsessile, subchartaceous, dark green and ± glossy adaxially, ± rusty brown abaxially in dried material; blades narrowly triangular-ovate to lanceoblong, (2–)3–5.8(–8.5) × 1.2–2.3(–2.6) cm, base cordate and amplexicaul, attenuate above the middle and ± acuminate at apex, acumen 6–14 mm long, obtuse or acute; midnerve, intramarginal nerves and transverse veins strongly impressed adaxially, prominent abaxially, the leaf thus appearing ± bullate; tranverse veins 6–8 pairs oriented at a slightly oblique angle relative to the midnerve; intramarginal nerves forming a series of shallow arches between the junctions with the transverse veins. Cymes (2–)3–5-flowered, solitary in the leaf axils, less often at the defoliated nodes of older branchlets; peduncles very slender, 6– 15(–24) mm long; axis often extended by a short internode 2–4 mm above the peduncle; bracts acicular, 0.5–1 mm long, persistent. Flowers on slender pedicels 3–5 mm long; hypantho-calyx cupulo-patellate, 1–1.5 × 2 mm, margin truncate and remotely 4-microdentate; petals white, ovateacuminate, 2 × 1 mm, base truncate to subcordate-auriculate, acumen c. 0.5 mm long, acute, margins scarious; stamens dolabriform, anthers 1.25 mm long, thecae situated fronto-ventrally, connective dorsally keeled and lacking a gland, posterior extremity acute; fully extended filaments not seen; epigynous chamber shallow, top of ovary marked by 8 prominent radial lines; style 5 mm long. Fruits globose, 7 mm in diam., lacking a calycinal crown.

Etymology. – The epithet fofifa is applied here as a noun in apposition, in honor of the FO.FI.FA Herbarium (TEF) where all of the known material of this species is housed.

Distribution and ecology. – Known from two localities in east-central Madagascar, i.e., the Réserve de Tampolo near Fénérive-Est, and another site c. 40 km to the west, at a place called Tsinjoarivo near the village of Tanamarina ( Fig. 2 ). The habitat at Tampolo is in littoral forest on sand. Elevation from near sea level to c. 700 m.

Conservation status. – Memecylon fofifa has two known locations and an estimated AOO of 8 km ². It is still poorly known and perhaps very rare, yet is presumed extant since the Tampolo forest remains more-or-less intact. Although threats in the Tampolo reserve are not well-documented, the species is provisionally assessed as “Vulnerable” [VU D2] in accordance with IUCN Red List Categories and Criteria ( IUCN, 2012).

Notes. – The affinity of M. fof ifa is clearly with M. cardiophyllum Cogn. , but compared to the material assigned to that species the peduncles and pedicels are much longer. The leaves are also unlike those of M. cardiophyllum in being ± bullate on the adaxial surface.

Paratypi. – MADAGASCAR. Reg. Atsinanana [Prov. Toamasina]: distr. Fénérive [Fenoarivo Atsinanana], village Tanamarina , Tsinjoarivo , 3.X.1963, fr., Service Forestier 21410 ( P, TEF); Tampolo , 25.III.1981, fr., Service Forestier 32204 ( TEF) .

Figures

Fig. 4. – Memecylon fofifa R.D. Stone. A. Flowering branch; B. Detail of young branchlet; C–E. Leaves; F. Inflorescence; G. Petal; H. Stamen; I. Fruit. [A–C, F–H: Service Forestier 32781, TEF; D, I: Service Forestier 21410, TEF; E: Service Forestier 32204, TEF] [Drawing: S. Burrows]

Fig. 2. – Geographic distribution of Memecylon complanatum R.D. Stone (closed circle), M. convergens R.D. Stone (closed diamonds), M. fofifa R.D. Stone (open circles), M. longipetiolatum R.D. Stone (open square), M. paraxenum R.D. Stone (closed star), M. potamicum R.D. Stone (closed triangle), M. pseudogaleatum R.D. Stone (closed cross), M. subchartaceum R.D. Stone (open stars), and M. unguiculare R.D. Stone (closed square), mapped on the bioclimatic zones of Madagascar (after CORNET, 1974; see SCHATZ, 2000).