Uvariodendron pilosicarpum Dagallier & Couvreur, 2023

Dagallier, Leo-Paul M. J., Mbago, Frank M., Couderc, Marie, Gaudeul, Myriam, Grall, Aurelie, Loup, Caroline, Wieringa, Jan J., Sonke, Bonaventure & Couvreur, Thomas L. P., 2023, Phylogenomic inference of the African tribe Monodoreae (Annonaceae) and taxonomic revision of Dennettia, Uvariodendron and Uvariopsis, PhytoKeys 233, pp. 1-200 : 1

Uvariodendron pilosicarpum Dagallier & Couvreur sp. nov.

Figs 40 , 41

Type.

Gabon - Nyanga • J.L.C.H. van Valkenburg 2540 (holotype: WAG! (WAG.1418718); isotypes: BR! (BR0000009320413), E, K, LBV, MO, P! (P01956020), WAG! (WAG.1418719, WAG.1418720)), concession SFN; 2°39'34.2'S, 10°27'03'E; alt. 200 m; 01 Nov. 2003 .

Diagnosis.

Ud. pilosicarpum resembles Ud. molundense and Ud. citriodorum but can be differentiated in having the longest leaves smaller than 25 cm (vs. longest leaves greater than 25 cm long), obovate leaves (vs. elliptic to oblong to obovate leaves), with base decurrent (vs. base rounded to convex) and monocarps ellipsoid, curved, acuminate and densely pubescent (vs. monocarps cylindrical, straight and pubescent to glabrate).

Description.

Tree 4-8 m tall, D.B.H. ca. 8 cm; young branches sparsely pubescent to glabrous, old branches glabrous. Petiole 4-7 mm long, 1.5-2.5 mm wide, sparsely pubescent to glabrous. Leaf lamina 178-243 mm long, 60-87 mm wide, length:width ratio 2.3-3.6, obovate, coriaceous, base decurrent, apex acuminate, acumen 13-21 mm long; surface above glabrous, surface below sparsely pubescent to glabrous when young, glabrous when old; midrib impressed above, raised below, glabrous above, glabrous below; secondary veins 12-19 pairs, weakly brochidodromous, impressed above, raised below; tertiary veins reticulate. Inflorescences borne on trunk and branches, composed of 1 flower. Flower pedicel unknown. Flowers bisexual, buds unknown. Mature flower unknown, measures taken from fruits. Bracts 1, ca. 10 mm long, ca. 12 mm wide, broadly ovate, semi clasping the pedicel, velutinous outside, glabrous inside. Sepals 3, 9-10 mm long, 12.5-18 mm wide (measures taken from young fruits), imbricate, pubescent outside, glabrous inside, color unknown. Outer petals unknown. Inner petals unknown. Stamens unknown. Carpels ca. 30, free. Fruiting pedicel 8-13 mm long, 3.5-5.5 mm in diameter, pubescent to sparsely pubescent. Monocarps 6 to 30, 23-32 mm long, 10-15 mm wide, length:width ratio 2.2-2.3, ellipsoid, curved, acuminate at apex, densely velutinous, bright green with brown indumentum to glaucous with silvery indumentum, with resinous fragrance when cut; sessile to shortly stipitate, stipe 0-2 mm long, 2-3 mm wide, densely pubescent. Seeds unknown.

Distribution.

Endemic to Lower Guinean Domain of the Guineo-Congolian Region: Gabon.

Habitat and ecology.

Lowland mature or secondary rain forest. Altitude: 100-200 m a.s.l.

Phenology.

Flowers and fruits collected in November.

Etymology.

The specific epithet refers to the densely pubescent monocarps, characteristic of this species.

Preliminary conservation status.

This species is known from only two occurrences in the Monts Doudou National Park in Gabon. The AOO is estimated at 8 km2. Based on criterion B it would qualify for Endangered EN B1(a)+2(a), but no other subcriteria (b or c) is met. The outlook for this species relies on the future of this protected area and its distribution depends on the effects of human activities or random events in an uncertain future. Following IUCN criterion D, it is thus assigned a preliminary conservation status of Vulnerable VU D2.

Additional specimen examined.

Gabon - Ogooué-Maritime • M.S.M. Sosef 2261 (BR, K, LBV, MO, WAG), Doudou Mountains National Parc, c. 5 km S of Camp Peny (CBG); 2°03'30'S, 10°28'12'E; alt. 100 m; 14 Nov. 2005.

Figures

Figure 40. Uvariodendron pilosicarpum Dagallier & Couvreur A full specimen sheet with young branch and leaves and fruit B fruit with some monocarps transversally cut C young fruit with remaining sepals and bract. A, B van Valkenburg 2540 (type) C Sosef 2261. Photos A Naturalis (https: // data. biodiversitydata. nl / naturalis / specimen / WAG. 1418718) B, C Leo-Paul Dagallier.

Figure 41. Distribution map of Uvariodendron pilosicarpum. Shades of grey represent elevation, from white (sea level) to darker grey (higher elevation). The inset shows the extent of the map over Africa.