Xylopia Linnaeus, Syst. nat., ed. 10, 2: 1250 [+1378]. 1759, nom. conserv.

Johnson, David M. & Murray, Nancy A., 2018, A revision of Xylopia L. (Annonaceae): the species of Tropical Africa, PhytoKeys 97, pp. 1-252 : 24-25

Xylopia Linnaeus, Syst. nat., ed. 10, 2: 1250 [+1378]. 1759, nom. conserv.

Xylopicrum P. Browne, Hist. Jamaic. 250-251 + t. 5, fig. 2. 1756. Xylopicron , orth. mut., Adanson, Fam. 2: 365. 1763. Type: Xylopia muricata Linnaeus, typ. conserv. (lectotype designated by Setten and Maas, Regnum Vegetabile 127: 99, 1993: Browne s. n., Herb. Linn. No. 1077.1 (LINN)).

Unona Linnaeus f., Suppl. pl. 270. Apr 1782. Bulliarda Necker, Elem. bot. 2: 321. 1790, nom. superfl., non Candolle, 1801. Type: Unona discreta Linnaeus f.

Krockeria Necker, Elem. bot. 2: 317-318. 1790. Type: Unona concolor Willdenow (lectotype, here designated).

Coelocline A. de Candolle, Mém. Soc. Phys. Genève 5: 208-209. 1832. Type: Coelocline acutiflora (Dunal) A. de Candolle.

Parartabotrys Miquel, Fl. Ned. Ind., Eerste bijv. 3: 374. 1860. Type: Parartabotrys sumatranus Miquel. Note: Name only appears as a nomen nudum in Fl. Ned. Ind., Eerste bijv. 1: 154, 1860.

Pseudanona (Baillon) Safford, J. Wash. Acad. Sci. 3: 17. 1913, as " Pseudannona ." Xylopia Section Pseudanona Baillon, Adansonia 4: 141-142. Jan. 1864. Type: Pseudanona amplexicaulis (Lamarck) Safford (lectotype, designated by Safford, J. Wash. Acad. Sci. 3: 18. 1913).

Description.

Trees up to 50 m tall with a straight bole rising to a small conical to rounded crown, with narrow buttresses or, in a few species, stilt roots at the base of the trunk, or shrubs, the branches, in a few species, lianescent; bark smooth to scaly, variable in color. Indument of simple hairs. Twigs persistently pubescent to glabrate, usually sparsely lenticellate, longitudinally wrinkled; nodes in many African species with two axillary branches. Leaf with blades chartaceous to coriaceous, lanceolate, oblong, elliptic, ovate, oblanceolate, or obovate, apex rounded to acuminate, base cuneate to rounded, sometimes decurrent on petiole, midrib impressed to slightly raised adaxially, raised abaxially, secondary veins brochidodromous to weakly brochidodromous, petiole short, usually shallowly canaliculate. Inflorescences axillary, occasionally arising from the leafless portions of branches, 1-32-flowered; peduncles 1 to several per axil or absent, pedicels 1-several per peduncle, with 1-6 small caducous to persistent bracts; buds ovoid to linear, apex obtuse to acute. Flowers bisexual. Sepals 3, usually connate at the base and forming a cuplike calyx, in a few species free and imbricate at base. Petals 6, in 2 series of three, free, white, cream-colored, pale yellow, pale orange, or, in a few species, red in vivo; outer petals erect, slightly spreading, or curved outward at anthesis, ovate to linear, flattened to a concave base adaxially, flat, often with a faint ridge, abaxially; inner petals slightly shorter and narrower (much shorter in X. rubescens ) than outer petals, ovate to linear, keeled on both surfaces but becoming concave at the base adaxially and flat at the base abaxially, often narrowed into a short claw; in a few species, the margins of the basal concavity are differentiated from the tissue of the rest of the petal. Stamens 40-200; fertile stamens clavate to oblong, apex of connective shieldlike, conical, globose, or rudimentary, often overhanging anther thecae, pubescent or papillate, rarely glabrous, anthers transversely septate, 4-24-locellate, filament much shorter than anther, articulated with the staminal cone; outer staminodes oblong to clavate, apex obtuse to obliquely truncate, rarely absent; inner staminodes often adhering to the bases of the stigmas, usually shorter than outer staminodes, clavate to oblong, apex rounded, rarely absent; filament bases connate into a staminal cone that partially or completely encloses the ovaries, the rim even or sometimes laciniate, or staminal cone absent. Carpels 2-50; ovaries oblong or ovoid, usually hairy, stigmas free or loosely connivent with tips spreading, linear, falciform, narrowly oblong, or clavate, smooth or studded with round tubercles in some species, often hairy at the apex. Torus flat or slightly concave. Fruit of up to 36 glabrate to pubescent dehiscent monocarps borne on a short woody pedicel and slightly expanded torus. Monocarps with green, red, or purple exterior and a green or pink to scarlet endocarp in vivo, linear, oblong, ovoid, or globose, often somewhat falcate, occasionally weakly torulose, apex rounded or with a curved beak or mucro, base contracted into a stipe or sessile, smooth, longitudinally ridged, finely wrinkled, or verrucose; pericarp leathery to woody when dried. Seeds up to 20 per monocarp, attached laterally in one or two rows, lying parallel, oblique, or perpendicular to long axis, oblong to ellipsoid, oblong, elliptic, or ovate in cross section, flattened at micropylar end, rounded at chalazal end, brown to black, smooth or rarely slightly pitted, dull or shiny, raphe/antiraphe forming a raised ridge encircling the seed or flat and not evident, micropylar scar elliptic to circular; seeds arillate, the aril attached around the micropyle, white, yellow, orange, red, pink, or violet in vivo, fleshy or papery, or aril absent; seed coat with a fleshy outer layer (sarcotesta) and hard inner layer, or sarcotesta absent.

A pantropical genus of ca. 180 species, in tropical Africa represented by 45 species. The only other African Annonaceae genus with elongate flower buds such as those commonly seen in Xylopia is Greenwayodendron Verdc., and the latter genus is sometimes mistaken for Xylopia on this basis; Greenwayodendron species, however, always have terminal inflorescences, which appear supra-axillary or leaf-opposed ( Verdcourt 1969). The dehiscent monocarps set Xylopia apart from all other African Annonaceae genera except the East African Mkilua Verdc. ( Verdcourt 1970) and Ophrypetalum Diels, neither of which has a brightly colored endocarp or seeds.

Patonia Wight ( Wight 1838) is usually treated as a generic synonym of Xylopia (van Setten and Maas 1990, Turner 2011). In his generic description, however, Wight explicitly described and mentioned an apical ovule and seed, and a calyx that grows up to cover the maturing fruit. These are characters of Diospyros , not of Annonaceae . We suggest that Hiern was correct in adopting the name Patonia as a synonym of Diospyros and that Patonia walkeri Wight should be its type, as the lectotype designated is in conflict with the generic protologue. Patonia parvifolia , the other species placed in the genus when it was proposed, is a Xylopia , now re-named Xylopia patoniae I. M. Turner for nomenclatural reasons ( Turner 2011).

Key to the African species of Xylopia

Xylopia Linnaeus, Syst. nat., ed. 10, 2: 1250 [+1378]. 1759, nom. conserv.

Xylopicrum P. Browne, Hist. Jamaic. 250-251 + t. 5, fig. 2. 1756. Xylopicron , orth. mut., Adanson, Fam. 2: 365. 1763. Type: Xylopia muricata Linnaeus, typ. conserv. (lectotype designated by Setten and Maas, Regnum Vegetabile 127: 99, 1993: Browne s. n., Herb. Linn. No. 1077.1 (LINN)).

Unona Linnaeus f., Suppl. pl. 270. Apr 1782. Bulliarda Necker, Elem. bot. 2: 321. 1790, nom. superfl., non Candolle, 1801. Type: Unona discreta Linnaeus f.

Krockeria Necker, Elem. bot. 2: 317-318. 1790. Type: Unona concolor Willdenow (lectotype, here designated).

Coelocline A. de Candolle, Mém. Soc. Phys. Genève 5: 208-209. 1832. Type: Coelocline acutiflora (Dunal) A. de Candolle.

Parartabotrys Miquel, Fl. Ned. Ind., Eerste bijv. 3: 374. 1860. Type: Parartabotrys sumatranus Miquel. Note: Name only appears as a nomen nudum in Fl. Ned. Ind., Eerste bijv. 1: 154, 1860.

Pseudanona (Baillon) Safford, J. Wash. Acad. Sci. 3: 17. 1913, as " Pseudannona ." Xylopia Section Pseudanona Baillon, Adansonia 4: 141-142. Jan. 1864. Type: Pseudanona amplexicaulis (Lamarck) Safford (lectotype, designated by Safford, J. Wash. Acad. Sci. 3: 18. 1913).

Description.

Trees up to 50 m tall with a straight bole rising to a small conical to rounded crown, with narrow buttresses or, in a few species, stilt roots at the base of the trunk, or shrubs, the branches, in a few species, lianescent; bark smooth to scaly, variable in color. Indument of simple hairs. Twigs persistently pubescent to glabrate, usually sparsely lenticellate, longitudinally wrinkled; nodes in many African species with two axillary branches. Leaf with blades chartaceous to coriaceous, lanceolate, oblong, elliptic, ovate, oblanceolate, or obovate, apex rounded to acuminate, base cuneate to rounded, sometimes decurrent on petiole, midrib impressed to slightly raised adaxially, raised abaxially, secondary veins brochidodromous to weakly brochidodromous, petiole short, usually shallowly canaliculate. Inflorescences axillary, occasionally arising from the leafless portions of branches, 1-32-flowered; peduncles 1 to several per axil or absent, pedicels 1-several per peduncle, with 1-6 small caducous to persistent bracts; buds ovoid to linear, apex obtuse to acute. Flowers bisexual. Sepals 3, usually connate at the base and forming a cuplike calyx, in a few species free and imbricate at base. Petals 6, in 2 series of three, free, white, cream-colored, pale yellow, pale orange, or, in a few species, red in vivo; outer petals erect, slightly spreading, or curved outward at anthesis, ovate to linear, flattened to a concave base adaxially, flat, often with a faint ridge, abaxially; inner petals slightly shorter and narrower (much shorter in X. rubescens ) than outer petals, ovate to linear, keeled on both surfaces but becoming concave at the base adaxially and flat at the base abaxially, often narrowed into a short claw; in a few species, the margins of the basal concavity are differentiated from the tissue of the rest of the petal. Stamens 40-200; fertile stamens clavate to oblong, apex of connective shieldlike, conical, globose, or rudimentary, often overhanging anther thecae, pubescent or papillate, rarely glabrous, anthers transversely septate, 4-24-locellate, filament much shorter than anther, articulated with the staminal cone; outer staminodes oblong to clavate, apex obtuse to obliquely truncate, rarely absent; inner staminodes often adhering to the bases of the stigmas, usually shorter than outer staminodes, clavate to oblong, apex rounded, rarely absent; filament bases connate into a staminal cone that partially or completely encloses the ovaries, the rim even or sometimes laciniate, or staminal cone absent. Carpels 2-50; ovaries oblong or ovoid, usually hairy, stigmas free or loosely connivent with tips spreading, linear, falciform, narrowly oblong, or clavate, smooth or studded with round tubercles in some species, often hairy at the apex. Torus flat or slightly concave. Fruit of up to 36 glabrate to pubescent dehiscent monocarps borne on a short woody pedicel and slightly expanded torus. Monocarps with green, red, or purple exterior and a green or pink to scarlet endocarp in vivo, linear, oblong, ovoid, or globose, often somewhat falcate, occasionally weakly torulose, apex rounded or with a curved beak or mucro, base contracted into a stipe or sessile, smooth, longitudinally ridged, finely wrinkled, or verrucose; pericarp leathery to woody when dried. Seeds up to 20 per monocarp, attached laterally in one or two rows, lying parallel, oblique, or perpendicular to long axis, oblong to ellipsoid, oblong, elliptic, or ovate in cross section, flattened at micropylar end, rounded at chalazal end, brown to black, smooth or rarely slightly pitted, dull or shiny, raphe/antiraphe forming a raised ridge encircling the seed or flat and not evident, micropylar scar elliptic to circular; seeds arillate, the aril attached around the micropyle, white, yellow, orange, red, pink, or violet in vivo, fleshy or papery, or aril absent; seed coat with a fleshy outer layer (sarcotesta) and hard inner layer, or sarcotesta absent.

A pantropical genus of ca. 180 species, in tropical Africa represented by 45 species. The only other African Annonaceae genus with elongate flower buds such as those commonly seen in Xylopia is Greenwayodendron Verdc., and the latter genus is sometimes mistaken for Xylopia on this basis; Greenwayodendron species, however, always have terminal inflorescences, which appear supra-axillary or leaf-opposed ( Verdcourt 1969). The dehiscent monocarps set Xylopia apart from all other African Annonaceae genera except the East African Mkilua Verdc. ( Verdcourt 1970) and Ophrypetalum Diels, neither of which has a brightly colored endocarp or seeds.

Patonia Wight ( Wight 1838) is usually treated as a generic synonym of Xylopia (van Setten and Maas 1990, Turner 2011). In his generic description, however, Wight explicitly described and mentioned an apical ovule and seed, and a calyx that grows up to cover the maturing fruit. These are characters of Diospyros , not of Annonaceae . We suggest that Hiern was correct in adopting the name Patonia as a synonym of Diospyros and that Patonia walkeri Wight should be its type, as the lectotype designated is in conflict with the generic protologue. Patonia parvifolia , the other species placed in the genus when it was proposed, is a Xylopia , now re-named Xylopia patoniae I. M. Turner for nomenclatural reasons ( Turner 2011).

Key to the African species of Xylopia