Uvariopsis sp. nov. 3 'Congo'

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

Uvariopsis sp. nov. 3 'Congo'

Fig. 89

Description.

Tree ca. 3.5 m tall, D.B.H unknown; young branches glabrous, old branches glabrous. Petiole ca. 2 mm long, ca. 2 mm wide, glabrous. Leaf lamina ca. 160 mm long, ca. 58 mm wide, length:width ratio ca. 2.8, elliptic, coriaceous, base rounded, apex attenuate, surface above glabrous, surface below glabrous; midrib impressed above, raised below, glabrous above, glabrous below; secondary veins ca. 9 pairs, brochidodromous, impressed above, raised below; tertiary veins reticulate. Flowers only flower bud seen. Flower buds ovoid to conical. Inflorescences axillary, composed of 1 flower. Peduncle inconspicuous. Flower pedicel 20-65 mm long, ca. 1 mm in diameter, glabrate to glabrous. Bracts 1 in the lower half of the pedicel, ca. 1 mm long, ca. 1 mm wide, broadly ovate, sparsely pubescent outside, glabrous inside. Sepals 2, ca. 2 mm long, ca. 3 mm wide. Petals 4, ca. 7 mm long, ca. 4 mm wide, length:width ratio red outside. Fruits unknown.

Distribution.

Endemic to Congolia Domain of the Guineo-Congolian Region. Only known from the Kasai-Oriental and Equateur regions in the Democratic Republic of the Congo.

Habitat and ecology.

Rain forests.

Phenology.

Flowers collected in May and October.

Notes.

This species resembles Up. solheidii and Up. noldeae in having elliptic leaves with rounded leaf base. It differs from Up. solheidii in having young branches and petioles completely glabrous (vs. tomentose in Up. solheidii ). It differs from Up. noldeae in having flowers borne on young branches and axillary (vs. borne on trunk in Up. noldeae , but see the discussion above about the unreliability of the flower position to discriminate the species), and in having flower pedicels 20-65 mm long (vs. 70-83 mm long in Up. noldeae ). This species is known from only two specimens from two different localities distant of more than 700 km from each other in the Congo bassin. It is thus likely to occur in other localities but further exploration of the region is necessary to confirm that.

Specimens examined.

Democratic Republic of the Congo - Equateur • C.M. Evrard 6276 (K); Ikela, Yalifake; 0°31'06'N, 22°38'12'E ; 06 May. 1959 - Kasai-Oriental • L. Liben 3854 (K); Mwene Ditu, Mwene Ditu, Mwene-Ditu; 7°00'S, 23°27'E ; 24 Oct. 1957.

Figures

Figure 89. Distribution map of Uvariopsis sp. nov. 3 ' Congo'. Shades of grey represent elevation, from white (sea level) to darker grey (higher elevation). The inset shows the extent of the map over Africa.