Diospyros ranirisonii G.E. Schatz, Lowry & Phillipson, 2020

Schatz, George E., Lowry Ii, Porter P. & Phillipson, Peter B., 2020, Taxonomic studies of Diospyros (Ebenaceae) from the Malagasy region. V. Synoptic revision of the Bernieriana group in Madagascar and the Comoro Islands, Candollea 75 (2), pp. 203-218 : 210-212

4. Diospyros ranirisonii G.E. Schatz, Lowry & Phillipson , sp. nov.

( Fig. 3 ).

Holotypus: MADAGASCAR. Reg. DIANA [Prov. Antsiranana]: forêt de Sahafary 20.II.1962, fr., Service Forestier 20972 ( P [ P03974996 ]!; iso-: MO-6956009 !, G [ G00341734 ]!, K!, P [ P00722703 ]!, TEF [ TEF000892 ]!, W!).

Diospyros ranirisonii G.E. Schatz, Lowry & Phillipson can be distinguished from other members of the Bernieriana group by its linear to narrowly oblong leaves with strongly revolute margins, the abaxial surface of the lamina obscured on many leaves, its female flowers narrowly ellipsoid, 11–15 mm long, at least 2 times longer than wide, with the apex of the calyx lobed, and its mature fruit 12–16 × 7–10 mm, the lobes of the calyx 6–8 mm long.

Tree 5 – 10 m tall, to 30 cm DBH. Young stems initially densely covered with erect, very short (<0.1 mm) gray trichomes and rufous, farinose trichomes, glabrescent. Leaves 0.9–4.4 × 0.3–0.8 cm, narrowly elliptic to linear, occasionally narrowly obovate, initially densely covered above and below with rufous farinose trichomes with a gray stellate/lepidote base, glabrescent, glossy above, base acute to cuneate, margin strongly revolute, the underside of the leaf often completely obscured, apex acute with the tip rounded, midrib slightly impressed above, raised below, covered with gray farinose trichomes, venation absent; petiole 2–4 mm, 0.8 mm diam., canaliculate, initially densely covered with rufous farinose trichomes and very short (<0.1 mm), semi-appressed white trichomes, glabrescent. Male flowers solitary in axils of leaves, narrowly ovoid to narrowly ellipsoid; pedicels 2 mm long, 1 mm in diam., usually curved, densely covered with rufous farinose trichomes and very short (<0.1 mm) semi-appressed, light golden trichomes; calyx tubular, 6 mm long, 2 mm in diam., densely covered with farinose trichomes and semiappressed light golden trichomes 0.2 mm long; corolla tubular, 7 mm long, 2 mm in diam., basal half glabrous, distal half densely covered with appressed trichomes <0.1 mm, lobes 3, 3 × 2 mm, densely covered with light golden, appressed trichomes <0.1. long outside, glabrous inside; stamens 9, adnate to corolla at the base, filaments 1.5 mm, adnate for 1 mm, free for 0.5 mm, anthers 0.8 –1 × <0.1 mm. Female flowers solitary in the axils of leaves and fallen leaves; pedicel 2–3 mm long, 2 mm diam., with 4 minute distichous bracteoles, densely covered with rufous farinose trichomes and very short (<0.1 mm), erect, light golden to gray trichomes; flowers narrowly ellipsoid at anthesis, 10– 11 mm long, 4– 5 mm in diam., calyx adnate to receptacle, 8–10 mm tall, the apex with (3–)4 lobes, 2 × 2–3 mm, slightly reflexed, densely covered outside with rufous farinose trichomes and sparse semiappressed light golden trichomes 0.5 mm long; calyx lobes rapidly expanding post anthesis, to 6–8 × 5–6 mm, succulent; corolla tubular, 10 mm long, tube 8 mm long, lobes 4, 2 × 2 mm, broadly triangular, densely covered with semi-appressed light golden trichomes; staminodia 9, filaments 1.2 mm, antherode 0.8 mm; ovary 3 mm long, 2 mm in diam., ellipsoid, basal third glabrous, upper 2/3 densely covered with short appressed light golden trichomes, stylar column narrowly conical, 3 mm. Pedicel in fruit expanding to 4–5 mm in diam. Fruit 12–16 mm long, 7–10 mm in diam., ellipsoid, initially enclosed within the prolonged calyx until it breaks off, glabrous to densely covered toward the apex with short (<0.1 mm), appressed, light golden trichomes, crowned by the style/stigma remnant, cone-shaped, 2 mm tall, 1 mm in diam. at base.

Etymology. – The species epithet honors Patrick Ranirison, who made many important collections from the Loky Manambato protected area while pursuing his doctoral studies and played a leading role in the establishment of the new Ampasindava and Galoko-Kalobinono protected areas.

Vernacular name and uses. – “Mapingo” (Andriambolonera & Bernard 275). Wood is used for the manufacture of furniture (Andriambolonera & Bernard 275).

Distribution and ecology. – Diospyros ranirisonii is known from dry forest on sand in the far north in DIANA and SAVA regions from the Sahafary forest south to the Bobankora forest ( MADAGASCAR CATALOGUE, 2020), at an elevation of 50– 230 m.

Conservation status. – Diospyros ranirisonii has a geographic range in the form of an EOO of 760 km ² and a minimum AOO of 32 km ². It is present in the Loky-Manambato protected area. At other localities, it is threatened by fire, forest clearing for agriculture, grazing, and exploitation for firewood and construction material, all of which are projected to result in continuing decline. With respect to the principal threat of forest clearing for agriculture, it exists at seven locations. Diospyros ranirisonii can therefore be assessed for its risk of extinction as “Vulnerable” [VU B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)].

Notes. – Diospyros ranirisonii can be distinguished from other members of the Bernieriana group by its narrowly elliptic to linear leaves with strongly revolute margins, initially densely covered with rufous farinose indumentum, narrowly ellipsoid female flowers at least 2 times longer than wide, and lobed calyx enclosing the fruit, the lobes 6–8 mm long in fruit.

Paratypi. – MADAGASCAR. Reg. DIANA [Prov. Antsiranana]: forêt d’Analafondro , 26.II.1964, fr., Service Forestier 23322 ( FHO, G, K, MO, P [2 sheets], TAN, TEF, US, W) ; ibid. loco, 7.II.1966, ♂ fl., Service Forestier 24522 ( G, MO, P, TAN, TEF), ibid.loco, 7.II.1966, ♀ fl., Service Forestier 24523 ( G, MO, P [2 sheets], TAN, TEF, W). Reg. SAVA [Prov. Antsiranana]: Ampondra, 3.X.2013, fr., Rabarijaona et al. 326 ( K, MO, P, TAN) ; Loky Manambato AP, 27.IX.2013, ster., Andriambololonera & Bernard 275 ( MO, TAN) ; ibid. loco, 16.IV.2004, fr., Ranirison 668 ( G, MO, P) ; ibid. loco, 14.IX.2013, fr., Onjalalaina et al. 21 ( BR, K, MO, P, TAN) ; ibid. loco, 11.II.2004, fr., Ranirison & Nusbaumer 417 ( G, MO) ; ibid. loco, 6.III.2003, fr., Gautier et al. 4241 ( G, MO, P) ; ibid. loco, 9.III.2004, fr., Gautier et al. 4506 ( G, MO, P).

Figures

Fig. 3. – Diospyros ranirisonii G.E. Schatz, Lowry & Phillipson. A. Flowering branch; B–C. Leaves (abaxial surface); D. Detail of female flower; E. Nearly mature fruit. [A, D: Service Forestier 24523, P; B–C, E: Service Forestier 20972, P] [Drawing: Alain Jouy]