Xylopia elliotii Engler & Diels, Monogr. afrik. Pflanzen-Fam. 6: 65. 1901.

Johnson, David M. & Murray, Nancy A., 2018, A revision of Xylopia L. (Annonaceae): the species of Tropical Africa, PhytoKeys 97, pp. 1-252 : 135-138

30. Xylopia elliotii Engler & Diels, Monogr. afrik. Pflanzen-Fam. 6: 65. 1901. Fig. 40

Type.

GUINEA ["Sierra Leone"]. Farana Region , riverside woods of Niger, Farana, 26 Mar 1892 (fl), G. F. Scott-Elliot 5325 (lectotype, here designated: B! [100153142]; isolectotypes: BM! [000510796, lower half of sheet], GH! K! [000199071], P! [00169156]) .

Description.

Shrub or small tree up to 10 (-18) m tall, much-branched; bark gray or dark brown. Twigs reddish brown to dark gray, eventually light gray, densely erect-hairy, the hairs 0.2-0.8 mm long, on new flushes of growth (bud scales still visible at base), eventually glabrate, sometimes with bark exfoliating; nodes commonly with two axillary branches. Leaf with larger blades 4.5-9.5 cm long, 1.8-5.6 cm wide, subcoriaceous, discolorous, lanceolate-ovate to elliptic, oblong, or oblong-lanceolate, apex obtuse, attenuate, emarginate, or acute, occasionally with a short acumen 4 mm long, base cuneate to rounded, short-decurrent on petiole, glabrous except for the pubescent midrib adaxially, finely appressed-pubescent to glabrate abaxially; midrib raised or impressed adaxially, raised abaxially, secondary veins indistinctly brochidodromous, 10-16 per side, diverging at 45-70° from the midrib, these and higher-order veins slightly raised on both surfaces; petiole 3.5-6 mm long, shallowly canaliculate, pubescent. Inflorescences axillary, 1(-2)-flowered, pubescent; pedicels not pedunculate, 3.0-6.1 mm long, 0.9-1.1 mm thick; bracts 2, one to either side of pedicel midpoint, caducous or persistent, 1.6-2.6 mm long, ovate to semicircular, apex acute to obtuse; buds linear-lanceolate, sometimes falciform, apex acute. Sepals slightly spreading at anthesis, 1/4-1/2-connate, 2.3-4.5 mm long, 2.5-3.6 mm wide, coriaceous, ovate to broadly ovate, apex acute or apiculate at the apex, densely sericeous abaxially. Petals white, tinged with purple at the base in vivo; outer petals spreading at anthesis, (12.6-) 19-32 mm long, 2.3-4 mm wide at base, 1.2-2.5 mm wide at midpoint, fleshy, linear, apex obtuse, densely puberulent adaxially, densely appressed-pubescent abaxially; inner petals bent outward from the base at anthesis, 16-24 mm long, 2.3-3.9 mm wide at base, 0.9-1.4 mm wide at midpoint, fleshy, linear, apex acute, base with undifferentiated margin, pubescent on both surfaces, becoming glabrous at base. Stamens ca. 120; fertile stamens 1.1-1.6 mm long, narrowly oblong-clavate, apex of connective 0.2-0.3 mm long, depressed-globose to shieldlike, overhanging the anther thecae, minutely papillate or glabrous, anthers 10-13-locellate, filament 0.2-0.5 mm long; outer staminodes 1.3-1.7 mm long, oblong to clavate, apex acute, obtuse or truncate; inner staminodes 0.8-1.1 mm long, oblong, apex truncate, occasionally innermost stamens reduced in size but still with a few anther locelli so not truly staminodial; staminal cone 1.4-1.8 mm in diameter, 0.6-1.3 mm high, completely concealing the ovaries, rim irregularly laciniate. Carpels 9-10; ovaries 1.3-1.5 mm long, linear-oblong, pubescent, stigmas connivent, 1.3-2.3 mm long, trowel-shaped, apex obtuse, glabrous or pubescent at the apex. Torus flat, 1.9-2.5 mm in diameter. Fruit of up to 8 sparsely pubescent to glabrate monocarps borne on a pedicel 10-12 mm long, 1.3-6 mm thick, glabrate; torus 2.5-16 mm in diameter, 2.5-4 mm high, depressed-globose. Monocarps with red- to purple-tinged green exterior and red endocarp in vivo, 2.0-3.8 cm long, 0.9-1.3 cm wide, 1.1-1.2 cm thick, irregularly oblong or obovoid, slightly torulose, apex rounded, base sessile or contracted into a stipe 3-6 mm long, 2-3 mm thick, slightly wrinkled, finely verrucose and somewhat shiny; pericarp 0.8-0.9 mm thick. Seeds up to 9 per monocarp, in two rows, lying oblique to perpendicular to long axis, 9.2-11.8 mm long, 6.8-7.8 mm wide, 5.3-6.8 mm thick, oblong to flattened-ellipsoid, elliptic to semicircular in cross-section, truncate at micropylar end, rounded at chalazal end, light brown, smooth, dull, raphe/antiraphe not evident, micropylar scar 3.5-4 mm long, 2-2.8 mm wide, broadly elliptic to obovate; sarcotesta unknown in vivo; aril absent.

Phenology.

Specimens with flowers have been collected from January to May, and with fruit from October to March and in May.

Distribution

(Fig. 41 ). Occurs from northeastern Sierra Leone eastward to Togo, then disjunct to central Cameroon and the Central African Republic, in gallery forest along streams and rivers and occasionally extending into drier uplands, at elevations of 280-1400 m.

Local names.

nkankalan jé ( Malinké, Duvall 271), ké (Westphal & Westphal-Stevels 10047, 10048, 10049, 10172), kenema (Nongowa, Jordan 2063).

Representative specimens.

GUINEA BISSAU. Gabú, Pitche, Cambore (Fondo de Cambore), 7 Dec 1955 (yg fr), Explorações Botânicas 3780 (B, FI-T, K, MO, WAG). GUINEA. Beyla, Moribadougou, Apr 1945 (fl), Adam 123 (K, MO, P); Macenta, Tènèmadou, 10 Aug 1949 (st), Adam 5917 (MO); Dalaba, Dalaba, 9 Apr 1956 (fl), Adam 11846 (MO); Chaine de Tibè, 1943 (fr), Adam 26905 (P); Macenta+Beyla Prefectures, Simandou Range, N of Pic de Fon, near the pass on path between villages Moribadou and Lamadou, 8°35'23"N, 8°53'52"W, 1040 m, 27 Mar 2008 (fr), van der Burgt 1167 (K); Fouta Djallon, 23 Apr 1907 (fl), Caille 18149 (P); Macenta+Beyla Prefectures, Simandou Range, Monts Simandou, Pic Dabatini, 8°33'16"N, 8°53'12"W, 1008 m, 23 Mar 2008 (fl), Haba 180 (K); environs de Pita, Jan 1936 (fr), Jacques-Félix 735 (P); Timbo, Mar 1907 (fl, fr), Pobéguin 1529 (P); Lorbé à Pita, May 1909 (fl), Pobéguin 2130 (P); in woods by Niger River, Farana, 26 Mar 1892 (fr), Scott-Elliot 5328 (GH, K); Beyla Prefecture, Tibé Mont., collines SE du Pic de Tibé, en face du village Sondou, 910 m, 8°50'27"N, 8°52'16"W, 10 Dec 2007 (fr), Traoré 35 (K). SIERRA LEONE. Nongawa, Kambui Forest Reserve, Neaboi Valley, 15 Apr 1955 (bud, fl), Jordan 2063 (K, P); Sulimania Road, Falaba Marsh, 24 Mar 1892 (fl), Scott-Elliot 5288 (B, GH, K, P). MALI. 32.8 km SW of Manantali, Arrondissement de Bamafélé, Cercle de Bafoulabé, Région de Kayes, 12°57.009'N, 10°36.613'W, 280-320 m, 12 Nov 1999 (fr), Duvall 371 (MO-4 sheets); near the village of Solo, northern edge of Korofing National Park (formerly Bafing Faunal Reserve), 1 3°00.362'N, 10°26.137'W, 29 Jan 2004 (st), Duvall 513 (MO); Pilimili Riv. Konnoa, s. d. (fl), Vuillet 68 (P). BURKINA FASO. Tourny (Cascade) (SW Haute Volta), 1 Mar 1971 (fr), Buonounou Ouétien 35 (P). IVORY COAST. Entre Odienné et Sangouani, 1 Mar 1973 (fl), Aké Assi 11969 (K). GHANA. Shiare, Buem-Krachi Dist., 2500' alt., 18 Apr 1959 (fl), Hall 1450 (K). TOGO. Sakoda, Apr 1905 (fl, old fr ped), Kersting I 84.a (A); without definite locality or date (fl), Kersting A.567 (GH, PH). CAMEROON. W. Cameroons, Ndop Plain, road to French Cameroons, 3800 ft, ca. 6°N, 10°30'E, 30 Mar 1962 (fl), Brunt 261A (K); Mbalang, 16 km E Ngdéré, 27 Jan 1978 (fl), Fotius 2984 (P); Tchal Mbabo, 16 Mar 1978 (fl), Fotius 3108 (P); Bayangam, Jan 1939 (fr), Jacques-Félix 2965 (P); Koutchamkap, Feb 1939 (fl), Jacques-Félix 3039 (P); Adamoua oriental, Hosséré Sillé, 20 Oct 1967 (fr), Jacques-Félix 8724 (P); Tibati, 10 Nov 1967 (fr), Jacques-Félix 9110 (P); Sadolkoulay (36 km E Ngaoundéré), 5 Dec 1964 (fr), Raynal & Raynal 12228 (P-2 sheets); a 20 km E de Foumbot, 5°34'N, 10°48'E, 1100 m, 26 Oct 1974 (fr), Sabatie 15 (MO, P); Près Katil-Foulbe, 50 km SE Ngaoundéré, 20 Oct 1983 (fr), Sabatie 687 (P); Bayangam, 17 May 1978 (fr), Westphal & Westphal-Stevels 10047 (P, WAG-2 sheets); Chutes de Tello, 45 km E de Ngaoundéré, 7°14'N, 13°57'E, 1250 m, 9 Apr 1983 (fl), van der Zon 2105 (WAG). CENTRAL AFRICAN REPUBLIC. Oubangui, Reg Zango, Jan 1920 (fl), Allouette s. n. (L); Chari Oriental (Pays dou Snoussi), [Voyage au Mamoun] Golo près Noellé, 7-28 Mar 1903 (fl), Chevalier 7741 (G, P-2 sheets); Manovo-Gounda-St. Floris National Park, 5 km S of Camp Koumbala along the Koumbala River (8°27'N, 21°13'E), 600 m, 3 Feb 1983 (fr), Fay 4191B (MO); Manovo-Gounda-St. Floris National Park, Koumbala River at Camp Koumbala, 08°29'N, 21°13'E, 590 m, 30 Mar 1983 (fr), Fay 4351 (K), 30 Mar 1983 (fl), Fay 4359 (K); Manovo-Gounda-St. Floris National Park, 9.3 km S of Koumbala Pende confluence on Pende Creek, 8°21'N, 21°14'E, 610 m, 15 May 1984 (fl), Fay 6641 (MO); région de Yalinga, Haut Oubangui, entre Wanda-Djalé et Wadda, 26 Feb 1922 (fl), Le Testu 3787 (BM, P, US); région de la Ouaka, région Ippy, Riv. Monga, 35 km NW Moronbas, 18 Feb 1925 (fl), Tisserant 1778 (BM, P).

Xylopia elliotii is more widespread than has been previously understood but has a number of characteristics consistent across its distribution: it is a small tree of gallery forest, the twigs have a dense indument of erect reddish brown hairs 0.2-0.8 mm long, the abaxial surface of the leaf blade has fine appressed hairs creating a dull surface to the leaf, the pedicels are somewhat elongate and always bear two bracts, one to either side of the pedicel midpoint (Fig. 40A-C ), and the monocarps are sessile to short-stipitate with seeds usually in two rows and with a thin pericarp.

The species is largely restricted to the Sudanian biogeographic region ( Linder et al. 2012) where few other species of Xylopia occur, but it is not an Upper Guinea endemic as indicated in Holmgren et al. (2004). There is a large disjunction in the distribution between Togo and Cameroon, and specimens from the eastern portion of the range tend to have slightly larger leaves and slightly longer pedicels and outer petals.

The collection McPherson 21337 (MO) from the Nimba Mountains of Guinea is problematic. The leaves and fruit resemble those of other specimens of X. elliotii from Guinea, but the habit, a tree 25 m tall, and the habitat, a forested slope at 860 m, are unusual for the species. The seeds were described as orange. A specimen identified as X. acutiflora in Robson (1960), Holmes H.1273 (K), from the Mwinilunga region of Zambia, also resembles X. elliotii in its reddish-brown erect twig pubescence and relatively long pedicels with only two bracts. The leaves on the specimen, however, are smaller than those of X. elliotii , the tree is described as occurring in mushitu swamp forest, and the specimen is widely disjunct from the range of X. elliotii .

There is little ecological information for Xylopia elliotii . The collections of Fay from Manovo-Gounda-St. Floris National Park, Central African Republic list the following associates in gallery or gallery-associated swamp forests: Adina microcephala , Gardenia imperialis , Ixora brachypoda , Ouratea flava , Rhynchospora corymbosa , Syzygium guineense , and Uapaca togoensis , as well as species of Ancistrophyllum , Berlinia , Cyrtosperma , Gaertnera , Mitragyna , and Raphia . The fragrance of the flowers was noted by several collectors. Two flowers on the collection Fay 6641 (MO) are distorted by galls, similar to those seen in flowers of X. mwasumbii .

Collections made by Westphal and Westphal-Stevels from the area of Bayangam, Cameroon, in 1978 document that the plant is locally kept around houses and the fruits used as a condiment. A collection by Jacques-Félix from the same locality made in 1939 notes that the plant is “cultivé” suggesting a long-standing local use for the fruits of this species.

The protologue for the name Xylopia elliotii Engl. & Diels gives the type locality as Sierra Leone, but Gledhill (1969) has documented that the type locality, Farana on the Niger River, is actually in present-day Guinea.

Figures

Figure 40. Xylopia elliotii. A Flower, side view, of specimen from Guinea B Flower bud, side view, of specimen from Central African Republic C Flower bud, side view, of isolectotype specimen from Sierra Leone D Seed, view of micropylar end and side view E Fruit F Habit. A from Adam 11846 (MO) B from Le Testu 3787 (P) C from Scott-Elliot 5325 (GH) D from Pobeguin 1529 (P) E from Scott-Elliot 5328 (GH) F from Scott-Elliot 5288 (BM).

Figure 41. Distribution of Xylopia elliotii. Bolder lines represent country borders, fainter lines lakes and major rivers.