Diospyros guineensis (Schumach. & Thonn.) E. Mestre, Meeprom, H. N. Rakouth & Lowry, 2025

Mestre Serra, Edgard, Puglisi, Carmen, Linan, Alexander G., Meeprom, Nattanon, Rakouth, Hasina N., Schmidt, Heidi H. & Lowry II, Porter P., 2025, A taxonomic revision of the continental African material previously included in Diospyros ferrea (Ebenaceae), Plant Ecology and Evolution 158 (1), pp. 82-99 : 82-99

2. Diospyros guineensis (Schumach. & Thonn.) E. Mestre, Meeprom, H. N. Rakouth & Lowry comb. nov.

Figs 1 B , 2 B

Ferreola guineensis Schumach. & Thonn. , Beskrivelse af Guineeiske Planter: 448. 1827. ( Schumacher and Thonning 1827)

Maba guineensis (Schumach. & Thonn.) A. DC. ( Candolle 1844: 231)

Diospyros ferrea (Willd.) Bakh. var. guineensis (Schumach. & Thonn.) Bakh. ( Bakhuizen van den Brink 1941: 433)

Type

GHANA – Volta Region • Quitta (= Keta); [5°54’S, 0°54’E]; Thonning s. n.; lectotype (designated here): C [ C 10003856 ] scan seen; isolectotypes: C [ C 10003857 , C 10003858 ] scans seen .

Description

Shrub ca 1.5 m tall. Bark grey, rugose, densely lenticellate, lenticels brown, elliptic to round. Young stems terete, pale grey, peeling to a darker grey bark, initially covered in sparse, semi-appressed, minute, yellowish hairs ca 0.3–0.7 mm long. Leaves alternate; petiole 1–4 mm long, 0.5–1 mm diam., somewhat glossy and tightly wrinkly (in sicco), terete to flattened above, with sparse, minute, semi-erect, white to yellowish-brown hairs or glabrescent; lamina 1.3–8.6 × 1–5.5 cm, elliptic to slightly ovate or obovate, symmetric (rarely slightly asymmetric), thinly coriaceous, glabrescent above, glabrescent or with scattered, semi-appressed, yellowish hairs ca 0.5 mm long below, concolourous to very slightly discolourous, shiny, with medium green-brown to reddish brown, dark, pitted glands sometimes present in pairs near the leaf base, rarely few elsewhere on the lamina, base attenuate to (broadly) acute, margin flat to weakly undulate and revolute, slightly thickened, sometimes paler than the leaf blade, apex acute, obtuse or nearly rounded, occasionally weakly and broadly acuminate; venation pinnate, midrib slightly impressed to flat above, raised below, secondary and tertiary venation usually visible on both sides, less conspicuous above, concolourous with the blade or slightly darker, raised on both sides; secondary venation acute or decurrent to the midrib, veins 5 or 6 (7) per side, weakly brochidodromous, forming irregular loops 1 / 2 to 2 / 3 of the way between the midrib and margin, the most apical smaller and more steeply angled; tertiary venation similar to the secondary in size and colour, irregularly reticulate and forming further loops between the secondary veins and the margin. Male flowers in 3 - to 6 - flowered axillary cymes or pseudo-umbels, axes with dense, semi-appressed, golden hairs <0.5 mm long, peduncle to 4 mm long, pedicel to 1 mm long; calyx with straight, appressed, golden to golden brown hairs 0.25–0.75 mm long inside and outside, denser closer to the inside margin, basal portion cupuliform, 1.5–2 × 2.5–3 mm, lobes 3, triangular, valvate, 1.5 × 1.5–2 mm, acute to broadly acute; corolla glabrous inside and outside except for a rhomboid central area of dense straight, appressed, golden hairs 0.75–1.25 mm long outside, tube narrowly urceolate, 2–2.5 × 2.5–3 mm, lobes 3, ovate, 2–2.5 × 2–2.5 mm, imbricate, apex acute; stamens 9 or 10, inserted at the base of the corolla tube, filament 0.5–1 mm, anther 1–1.5 mm; pistillode discoid, ca 0.5 × 1–1.5 mm, densely covered in erect, straight golden hairs ca 0.25–0.5 mm long. Female flowers axillary (branches sometimes appearing spike-like when leaves abscise prior to anthesis), solitary, rarely in pairs, pedicel 0.5–1.5 mm long, with sparse, semi-appressed, golden hairs <0.5 mm long; calyx moderately covered outside and inside in straight, appressed, whitish-golden hairs ca 0.25 mm long, basal portion cupuliform, 2–2.5 × ca 3 mm, lobes 3, broadly triangular, valvate, ca 1 × 2 mm, obtuse; corolla glabrous except for a rhomboid central area of dense straight, appressed, whitish-golden hairs 0.3–0.5 mm long, glabrous inside, tube cylindrical to slightly urceolate, 2.5–3 × ca 2 mm, lobes 3, broadly ovate, spreading, ca 3 × 2.5 mm, weakly imbricate, apex rounded; staminodes lacking; ovary ovoid, rounded-triangular in cross section, ca 1.5 × 1.5–2 mm, densely covered in straight, appressed, golden hairs ca 0.5 mm long, style 1–1.5 mm long, glabrous. Fruits axillary, solitary, pedicel to 0.5–1.5 mm; calyx cupuliform, 5–7 mm wide, with short, dense, appressed, pale hairs <0.5 mm long, denser inside, basal portion cupuliform, not closely appressed to the fruit wall (in sicco), 2–3.5 × 5–7 mm, lobes 3, broadly triangular, entire, 0.5–2.5 × 4–6 mm, apex broadly acute to obtuse; fruit ellipsoid to slightly ovoid, 8–12 × 6–8 mm, orangish brown (in vivo), surface smooth, with sparse, appressed, golden hairs ca 0.5 mm long, denser toward the apex, style persistent at the apex. Seeds 1 to 3, 9–10 × 3–4.5 mm, narrowly ovoid to ovoid-wedge shaped, minutely verrucose, dark grey, dull.

Distribution

Ghana, Ivory Coast, and Benin (Fig. 4 ).

Habitat

Diospyros guineensis is known from coastal areas, on sandy or rocky soil behind dunes, at elevations close to sea level.

Phenology

Flowering material has been collected in May and August to October, and fruiting material in February and April.

Preliminary IUCN conservation assessment

Diospyros guineensis has an Extent of Occurrence of 49,057 km 2 and a minimum Area of Occupancy of 48 km 2. The species is known from 12 collections made between 1907 and 1975 and a more recent one made in 1994, representing eight different occurrences, none of which fall within any formally protected areas and are therefore likely subjected to various threats including fire and land clearing for agriculture. Targeted collecting at all these sites is needed to confirm the status of the extant subpopulations. A continuing decline is inferred for the extent of occurrence, area of occupancy, area, extent, and / or quality of habitat, number of locations, and number of mature individuals. With respect to the most serious plausible threat (land clearing), Diospyros guineensis has been recorded at eight locations and is thus assessed as Vulnerable: VU B 2 ab (i, ii, iii, iv, v).

Additional material examined

BENIN – Littoral Department • Cotonou ; [06°21’23”N, 02°18’50”E]; 20 Mar. 1910; Chevalier 23364; P [ P 04595323 , P 04595320 ] • Cotonou ; [06°21’32”N, 02°19’35”E]; 29 Mar. 1910; Debeaux 345; K, P [ P 04595321 , P 04595322 ] .

GHANA – Without locality data • 20 Feb. 1932; Aubréville 903; P [ P 04595333 ] .

IVORY COAST – Abidjan District • Abouabo ; [05°17’56”N, 04°01’10”W]; 16 Oct. 1949; Adam 6498; P [ P 04595328 ] • Port-Bouët ; [05°14’30”N, 03°52’10”W]; 1932; Aubréville 1514; BR [ BR 0000016101500 ], P [ P 04595334 ; P 04595335 ] . – Bas-Sassandra District • Sassandra Port ; [04°56’24”N, 06°05’54”W]; 3 May 1907; Chevalier 17946; BR [ BR 0000016101487 ], FHO [ FHO-131141 ], P [ P 04595324 , P 04595325 , P 04595326 ], WAG [ WAG.1777958 ] . – Lagunes District • Entre Jacqueville et Toukouzou ; [05°09’00”N, 04°47’24”W]; 0–50 m; 18 Apr. 1994; Aké Assi 18943; MO [ MO-5657500 ] . – Montagnes District • Fabou ; [04°22’03”N, 07°30’59”W]; 12 Aug. 1907; Chevalier 19932; BR [ BR 0000016101494 ], FHO [ FHO-131142 ], P [ P 04595332 ], WAG [ WAG.1777956 ] . – Mouri Region • Mouri, near Cape Coast ; [05°07’37”N, 01°13’13”W]; 26 Apr. 1961; Hall 1907; K [ K 001561026 ] . – Woroba District • East of Tabou ; [04°25’00”N, 07°20’00”W]; 10 m; 3 Sep. 1975; Beentje 853; BR [ BR 0000016101357 ], K, MO [ MO-6573490 ], WAG [ WAG.1777954 , WAG.1777955 ] • Tabou ; [04°26’17”N, 07°19’02”W]; 17 Aug. 1907; Chevalier 19961 bis; P [ P 04595329 ] • Tabou ; [04°25’00”N, 07°21’00”W]; 11 Sep. 1975; de Koning 6007; BR [ BR 0000016101340 ], MO [ MO-6347092 ], WAG [ WAG.1777951 ], NY [ NY 02610014 ] .

Notes

Chevalier (1920: 396) listed the name ‘ Diospyros guineensis ’ in the first volume of his Exploration botanique de l’Afrique occidental française, but it was not validly published because he failed to provide a description or diagnosis, or a reference to a previously and effectively published description or diagnosis, rendering it illegitimate, as per Article 38.1 of the ICN ( Turland et al. 2018).

Figures

Figure 1. Leaves of Diospyros depicting abaxial (left) and adaxial (right) surfaces. A. D. angolensis (Gossweiler 9182, K 001561021). B. D. guineensis (de Koning 6007, NY 02610014). C. D. moutsambotei (Tadjouteu 570, BR 0000009522992). D. D. smeathmannii (Morton SL 1201, MO- 2865964). E. D. suaheliensis (Faulkner 2151, K 001561011). Photos by Alexander Linan.

Figure 2. Fruits of Diospyros. A. D. angolensis (holotype, Gossweiler 789, P 04595254). B. D. guineensis (Aubréville 903, P 04595333). C. D. moutsambotei (Bidault et al. 4494, MO- 6956210). D. D. smeathmannii (Jongkind 4327, MO- 6379106). E. D. suaheliensis (Faulkner 2151, K 001561011). Photos by Porter P. Lowry II.

Figure 4. Distribution map in Africa of the five species recognized among the African material previously included in Diospyros ferrea.