Piptostigma mortehanii De Wild., Bull. Jard. Bot. Etat Bruxelles 4: 383, 1914

Couvreur, Thomas L. P., Dagallier, Leo-Paul M. J., Crozier, Francoise, Ghogue, Jean-Paul, Hoekstra, Paul H., Kamdem, Narcisse G., Johnson, David M., Murray, Nancy A. & Sonke, Bonaventure, 2022, Flora of Cameroon - Annonaceae Vol 45, PhytoKeys 207, pp. 1-532 : 297-299

Piptostigma mortehanii De Wild., Bull. Jard. Bot. Etat Bruxelles 4: 383, 1914

Figs 90 , 92 ; Map 11G

= Piptostigma fouryi Pellegr., Notul. Syst. (Paris) 14: 75, 1950. Type. Cameroon. Central Region, Otottomo forest reserve, near Yaoundé, Foury P. 73, 1935: holotype: P[P00363302].

= Piptostigma mortehanii De Wild. var. Piptostigma mortehanii pilosa Sillans, Rev. Int. Bot. Appl. Agric. Trop. 33: 554, 1953. Type. Central African Republic: Lobaye, Oubangui, Région de Boukoko, Tisserant C. 2335, 9 Jan 1952: holotype: P[P00363279]; isotypes: P[P00363278, P00363280].

= Piptostigma longipilosum Mildb. & Diels ex. Engl. var. subnudum Tisserant, Not. syst. 15: 327, 1953. Type. Central African Republic: Lobaye, Oubangui, Région de Boukoko, Tisserant C. 2335, 9 Jan 1952: holotype: P[P00363279]; isotypes: P[P00363278, P00363280].

Type.

Democratic Republic of the Congo. Equateur; Dundusana, Mortehan M.G. 626, Oct 1913: lectotype, sheet here designated: BR[BR0000008802118]; isotype: BR[BR0000008802798] .

Description.

Tree, 8-10 m tall, d.b.h. 18 cm; stilt roots or buttresses absent, trunk funneled. Indumentum of simple hairs; old leafless branches glabrous, young foliate branches pubescent to hirsute, hairs to 2 mm long. Leaves: petiole 3-4 mm long, 2-3 mm in diameter, hirsute, cylindrical, blade inserted on top of the petiole; blade 11.5-20.1 cm long, 3-12.5 cm wide, obovate, apex acuminate, acumen 0.2-0.6 cm long, base acute, papyraceous, below sparsely pubescent when young and old, above pubescent when young, glabrous when old, discolorous, whitish below; midrib impressed, above pubescent when young and old, below densely pubescent to tomentose when young and old; secondary veins 24 to 34 pairs, sparsely pubescent above; tertiary venation percurrent. Individuals bisexual; inflorescence cauliflorous, peduncle like base 18-30 mm long, axial internodes 10-105 mm long, lax to panicle-like, sympodial rachis 40-320 mm long. Flowers with 9 perianth parts in 3 whorls, 2 to 8 per inflorescence; pedicel 5-8 mm long, ca. 2 mm in diameter, pubescent; in fruit 10-15 mm long, ca. 3 mm in diameter, pubescent; basal bract ca. 6 mm long, ca. 4 mm wide; upper bract ca. 6 mm long, ca. 4 mm wide; sepals 3, valvate, free, 4-5 mm long, 4-5 mm wide, ovate, apex acute, base truncate, brown, pubescent outside, glabrous inside, margins flat; petals free, outer petals shorter than inner; outer petals 3, 8-9 mm long, 4-5 mm wide, ovate, apex acute, base truncate, yellow, margins flat, pubescent outside, glabrous to pubescent, base glabrous inside; inner petals 3, valvate, 15-20 mm long, 4-7 mm wide, elliptic, apex acute, base truncate, greenish yellow, margins wavy, pubescent outside, tomentose inside; stamens 40, in 6 to 7 rows, ca. 2 mm long, broad; connective discoid, glabrous, red; staminodes absent; carpels free, 4 to 5, ovary ca. 2 mm long, stigma lobed, pubescent. Monocarps sessile, 1 to 2, 18-23 mm long, ca. 18 mm in diameter, ellipsoid, apex mucronate or rounded, pubescent to tomentose, verrucose, irregularly ribbed, white pink turning wine red to dark sepia when ripe; seeds 2 to 8 per monocarp, ca. 12 mm long, ca. 15 mm in diameter, ellipsoid; aril absent.

Distribution.

From Cameroon to the Democratic Republic of the Congo, one specimen from Ghana and two from Gabon; in Cameroon known from the South, Central, Littoral and South-West regions.

Habitat.

A common species when present; in lowland rain forest understory, often on inundated or swampy soils and along rivers. Altitude 30-700 m a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

Least Concern (LC) ( Cosiaux et al. 2019a n).

Uses in Cameroon.

None reported.

Notes.

Piptostigma mortehanii is easily distinguished by its densely pubescent or tomentose midrib and secondary veins on the lower side of the leaf blade, which sometimes has a brownish aspect like P. calophyllum . In some specimens, the hairs on the petiole and young foliate branches are long and hispid (i.e. the type specimen of Piptostigma fouryi ), resembling P. longepilosum , but in the later species these hairs are significantly longer (1 mm vs. more than 4 mm). In addition, the leaf blade base of the latter is rounded while in P. mortehanii it is acute.

Piptostigma mortehanii produces the longest inflorescences of the genus, which can be to up 2.7 m long with axial internodes up to 10.5 cm. However, this is quite variable within the species, and the inflorescence ranges from compact to panicle-like.

Specimens examined.

Central Region: Ottotomo Forest Reserve 3 km after reserve base near small loggers road, 3.66°N, 11.28°E, 02 May 2013, Couvreur T.L.P. 436 (WAG,YA); Ottotomo Forest Reserve 45 km South of Yaoundé 5 km on path into reserve, 3.65°N, 11.32°E, 15 January 2015, Couvreur T.L.P. 667 (WAG,YA); Yaoundé, 3.87°N, 11.52°E, 01 January 1935, Foury P. 73 (P); Route vétère (Likouk-Likoundji), 3.48°N, 10.32°E, 14 January 1974, Mezili P. 250 (P,WAG,YA). Littoral Region : Ca 40 km NW of Eséka on the other border of Kele River W of Yaoundé, 3.82°N, 10.48°E, 13 December 1963, de Wilde W.J.J.O 1476 (B,BR,MO,P,WAG,YA). South-West Region: Boa, 4.62°N, 9.3°E, 03 May 1994, Ndam N. 1205 (K); Korup National Park, 4.98°N, 8.85°E, 01 April 1979, Thomas D.W. 1110 (K) .

Figures

Map 11. A Piptostigma glabrescens B Piptostigma goslineanum C Piptostigma longepilosum D Piptostigma macranthum E Piptostigma macrophyllum F Piptostigma mayndongtsaeanum G Piptostigma mortehanii H Piptostigma multinervium I Piptostigma oyemense. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 90. Piptostigma multinervium A leaf B inflorescence C receptacle, inner petals removed D stamen E carpel side view and detail of ovules F monocarp. Piptostigma mortehanii G leaves H details of leaf, lower side I inflorescence J flower, inner petals removed A-F from Lolo 6 G-J from Foury C. 73. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris; 1 - 6 modified from Le Thomas (1969 b, pl. 21, p. 123).

Figure 92. Piptostigma mortehani A single monocarp B base of leaf blade, lower side C base of leaf blade, upper side. Piptostigma pilosum D leaf, lower side, note numerous secondary veins E base of leaf blade, upper side F inflorescence with two flowers, side view. Piptostigma submontanum G leaf, lower side, note numerous secondary veins H base of leaf blade, upper side I base of leaf blade, lower side J cauliflorous inflorescence, note compact nature A Bidault 3633, Gabon B, C Couvreur 436, Ebolbom, Cameroon D, E Couvreur 1070, Gabon F Bidault 1414, Gabon G-J Couvreur 625, Ebo, Cameroon. Photos B-E, G-J Thomas L. P. Couvreur A, F Ehoarn Bidault. Tropicos. org, Missouri Botanical Garden.