Xylopia sclerophylla D.M.Johnson & N.A.Murray, 2020

Johnson, David M. & Murray, Nancy A., 2020, A revision of Xylopia L. (Annonaceae): the species of Madagascar and the Mascarene islands, Adansonia 42 (1), pp. 1-88 : 80-82

33. Xylopia sclerophylla D.M.Johnson & N.A.Murray , sp. nov. ( Figs 2G, H ; 27A-K )

In its sericeous abaxial leaf surfaces most similar to Xylopia lastelliana , but differing in the leaves that are subcoriaceous with slightly revolute margins, 2.9-3.9 cm long and 0.9-1.2 cm wide, and obtuse to rarely acute at the apex, as well as monocarps that are longitudinally ridged, while the leaves of X. lastelliana are usually chartaceous, rarely subcoriaceous, have flat margins, are 3.5-6.7 cm long and 1.1-2.5 cm wide, and have acute to acuminate apices; the monocarps of X. lastelliana lack longitudinal ridges.

TYPE. — Madagascar. Prov. Antsiranana [“ Centre (Nord )”], Massif de la Montagne d’Ambre , rive droite de la Rivière des Makis entre la Station des Roussettes et la grande cascade, 18-20.XI.1958 (fl., fr.), Capuron 20041 SF (holo-, BR!; iso-, K[K001208409]!, OWU!).

PARATYPES. — Madagascar. Prov. Antsiranana, Sous-préfecture de Vohemar, commune rurale de Daraina, Daraina, forêt d’Ansahabe , 13°13’S, 49°33’E, 585 m, 13.I.2004 (fr.), Nusbaumer LN 943 (G, K, MO, P[P06774750]) ; sous-préfecture de Vohemar, commune rurale de Daraina, forêt de Binara (13°15’S, 49°37’E, 600 m, 11.XI.2005 (fr.), Nusbaumer & Ranirison LN 1693 (G, P[P06901367]) ; sous-préfecture de Vohemar, commune rurale de Daraina, forêt de Binara , 13°15’S, 49°37’E, 702 m, 6.XII.2005 (fr.), Nusbaumer & Ranirison LN 2328 (G) ; Montagne d’Ambre , partie nord, 12°29’13”S, 49°10’28”E, 770 m, 19.XII.2011 (fr.), Ramandimbimanana & Randimbiarison SDR 186 ( MO) ; Vohemar, Daraina, Daraina , forêt sur montagne, au sud d’Antampon’Ambilodambo, 13°09’28”S, 49°38’20”E, 681 m, 18.XI.2005 (fr.), Razafitsalama et al. 851 ( MO) .

DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Xylopia sclerophylla , sp. nov., is known only from northern Madagascar, where it occurs in humid evergreen forests at elevations of 585-770 m ( Fig. 30 ). The specimen with flowers was gathered in November, those with fruits from November to January. With an EOO of 859 km 2 and an AOO of 20 km 2, this species is given a preliminary conservation assessment of Endangered ( Table 2 ).

LOCAL NAME. — Hazoambo (Capuron 20041 SF).

DESCRIPTION Tree up to 16 m tall; d.b.h. up to 22 cm.

Twigs densely pubescent, the hairs 0.2-0.6 mm long, at length glabrate; nodes with one or occasionally two axillary branches.

Leaves with larger blades 2.9-3.9 cm long, 0.9-1.2 cm wide, subcoriaceous, concolorous or slightly discolorous and then purplish brown adaxially, light brown abaxially, lanceolate to oblong-lanceolate, apex acute to obtuse, base cuneate and short-decurrent on the petiole, margin slightly revolute, glabrous or with hairs on the midrib adaxially, densely and finely sericeous abaxially; midrib slightly darkened adaxially, secondary veins weakly brochidodromous, 8-11 per side, di- verging at 50-75° from midrib, these and higher-order veins raised adaxially, slightly raised but indistinct abaxially; petiole 2-3 mm long, shallowly canaliculate, smooth, pubescent.

Inflorescences axillary, 1-2-flowered, pedunculate or not, densely sericeous-pubescent; peduncle 0.9-1.0 mm long; pedicels 2 per peduncle or arising separately from leaf axil, 4.2-6.8 mm long, 0.5-0.7 mm thick; bracts 2, one attached near midpoint and the other just proximal to the sepals, usually caducous, 1.6-1.8 mm long, ovate; buds linear-lanceolate, apex obtuse.

Sepals spreading at anthesis, 1/8-¼-connate, 1.1-1.8 mm long, 2.0- 2.3 mm wide, coriaceous, broadly triangular to nearly semicircular, apex acute, densely sericeous abaxially.

Petals with color in vivo unknown; outer petals erect at anthesis, 12.7-14.5 mm long, 2.6-3.3 mm wide at base, 1.2-1.7 mm wide at midpoint, subcoriaceous, linear to linear-lanceolate, keeled only at the apex adaxially, indistinctly keeled abaxially, apex obtuse, pubescent except for glabrous concave base adaxially, sericeous abaxially; inner petals curved outward from the base with the apices curved inward at anthesis, 10.5- 12.7 mm long, 1.9-2.7 mm wide at base, 0.8-0.9 mm wide at midpoint, subcoriaceous, linear-subulate, keeled on both surfaces except for the adaxial basal concavity, apex obtuse, base concave with undifferentiated margin, densely puberulent except for glabrous base on both surfaces.

Stamens c. 100; fertile stamens 0.9-1.1 mm long, narrowly oblong, anther connective apex 0.2-0.3 mm long, depressed-globose, overhanging anther thecae, papillate, anthers 6-8-locellate, filament 0.3-0.4 mm long; outer staminodes 1.1-1.2 mm long, oblong to clavate, apex rounded to truncate; inner staminodes c. 0.8 mm long, oblong to clavate, apex truncate; staminal cone 1.3-1.5 mm in diameter, 0.5-0.8 mm high, concealing all but the apices of the ovaries, rim irregularly laciniate.

Carpels 4-6; ovaries c. 0.9 mm long, narrowly oblong, densely pubescent, stigmas connivent, 1.7-1.8 mm long, narrowly oblong, pubescent at apices.

Fruit of up to 8 monocarps borne on a pedicel 6-8 mm long, 2.5-5.5 mm thick, glabrate; torus 7-15 mm in diameter, 4.5- 9 mm high, depressed-globose; monocarps with green to red exterior and pink endocarp in vivo, 2.3-3.9 cm long, 1.4-2.4 cm wide, 1.2-2.1 cm thick, ellipsoid, ovoid, or oblong, not torulose, apex obtuse to rounded, base sessile or contracted into a stipe 1-2 mm long, 5-6.5 mm thick, somewhat verrucose, weakly wrinkled, occasionally lenticellate, ridged longitudinally, glabrate; pericarp 2.1-2.3 mm thick.

Seeds up to 4 per monocarp, in a single irregular row, perpendicular to long axis, 12-13 mm long, 8.2-8.7 mm wide, 5.8-7.3 mm thick, oblong to ellipsoid, ovate to semicircular in cross-section, brown to light brown, smooth, dull, perichalazal ring faintly visible but not elevated; sarcotesta pale green to green-yellow in vivo; aril absent.

NOTES

Xylopia retusa , sp. nov., and X. sclerophylla , sp. nov., have the smallest leaves of any Madagascar Xylopia species, but the subcoriaceous leaves of X. sclerophylla , sp. nov., are thicker. The monocarps have a thicker pericarp and are rounded at the apex, and the seeds have a green rather than orange sarcotesta. Xylopia sclerophylla , sp. nov., also resembles X. lastelliana in the sericeous indument of the abaxial leaf surfaces, but its leaves are consistently much smaller and thicker and are obtuse to occasionally acute rather than acuminate. The inland upland habitat also sets it apart from these two more coastal species.

The label of Nusbaumer LN 943 reports that lemurs eat the fruits, but no details were given as to the species of lemur eating the fruits or the part of the fruit eaten by the animals.

Figures

FIG. 2. — Fruits and seeds of Madagascar Xylopia L. species: A, fruits of X. retusa, sp. nov., showing at left a dehiscent monocarp with one seed covered by an orange sarcotesta (Rabenantoandro et al. 1249); B, fruit of X. perrieri Diels, one monocarp dehiscing to reveal barely visible seed with light green sarcotesta (Antilahimena 7187); C, dehiscing monocarps of a Xylopia sp., possibly X. carinata, sp. nov., with orange sarcotesta of seeds visible; D, fruit of X. bemarivensis Diels, with one dehiscing monocarp and seed with orange sarcotesta visible (Ranirison PR 808); E, immature fruit of X. flexuosa Diels, showing the elongate monocarp characteristic of species in sect. Xylopia (Rakotovao 4687); F, fruit of X. humblotiana Baill., with one dehisced monocarp and black seeds with white arils visible (Rakotovao 4886); G, fruits of X. sclerophylla, sp. nov.; monocarp at lower right is probably recently dehisced because green sarcotesta of seed is fully intact (Nusbaumer LN 943); H, dehisced monocarp of X. sclerophylla, sp. nov., at a slightly later stage, showing the sarcotesta collapsing and losing its color (Nusbaumer LN 943). Photos: A, P. P. Lowry II; B, P. Antilahimena; C, J. Tan; D, P. Ranirison (© Conservatoire et Jardin botaniques de la Ville de Genève); E, F, C. Rakotovao; G, H, by L. Nusbaumer (© Conservatoire et Jardin botaniques de la Ville de Genève). A, B, D, E, F, used under the terms of the Creative Commons license for Tropicos,the botanical information system at the Missouri Botanical Garden; C, used under the terms of the the Creative Commons license for iNaturalist.

FIG. 27. — Xylopia sclerophylla, sp. nov.,and X.retusa, sp. nov. A-K, X. sclerophylla, sp. nov.: A, leaves;B, leaf base, lower surface;C, flower, side view; D, flower bud,side view;E, inner petal,adaxial surface;F, outer petal,adaxial surface;G, monocarps;H, seed, side view;I, seed, view of micropylar end; J, stamen,abaxial view; K, outer staminode, abaxial view. L-R, X. retusa, sp. nov.: L, leaves; M, leaf base, abaxial surface; N, monocarps; O, seed, side view; P, seed, view of micropylar end; Q, outer petal, adaxial surface; R, inner petal, adaxial surface. A-K, from Capuron 20041_SF (OWU); L-N, from Capuron 28060_SF (B); O, P, from Ludovic & Rakotoarivony 212 (OWU); Q, R, from Rabevohitra et al. 5073 (OWU). Scale bars: A, G-I, L, N-P, 1 cm; B-D, M, 5 mm; E, F, Q, R, 3 mm; J, K, 1 mm.

FIG. 30. — Distributions of Xylopia perrieri Diels, X. ravelonarivoi, sp. nov., X. retusa, sp. nov., X. sclerophylla, sp. nov., X. sericolampra Diels and X. sahafariensis Cavaco & Keraudren on Madagascar.