Xylopia ambanjensis Cavaco & Keraudren, 1956

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 : 38-42

11. Xylopia ambanjensis Cavaco & Keraudren ( Fig. 14L-P )

Bulletin de la Société botanique de France 103: 275, 276 (1956). — Type: Madagascar. Prov. Antsiranana [“ Domaine du Sambirano ”], Anaborano-Ambanja, 18.IX.1951 (fl.), Service Forestier 3878 (holo-, P[P030362]!; iso-, TEF[photo]!).

MATERIAL EXAMINED. — Madagascar. Prov. Antsiranana. Ampasindava, forêt de Betsitsika, 13°45’38”S, 47°59’27”E, 21.I.2009 (fr.), Ammann et al. MYA 304 (K n.v., MO) ; Sava Region , Vohemar , Ampisikina , Ambararatamisakana, sur flanc rocheux du sommet d’Antseramborona, 12°57’10”S, 49°36’52”E, 510 m, 29.IX.2013 (fr.), Andriamiarinoro et al. 369 ( MO, P[P01047533]) ; Ambobaka , on savoka, Fiv. Ambanja, 13°44’54”S, 48°31’59”E, 200 m, 8.IV.2000 (fr.), Antilahimena et al. 455 ( MO, P[P01954132]) ; Réserve spéciale de Manongarivo, Ambongomirahavavy (13°59’S, 48°17’E), confluence Manongarivo / Marofotrotro, 100 m, 29.IX.1996 (fl.), Gautier et al. LG 3160 (K, P[P01954145]) ; Réserve spéciale de Manongarivo, Ambahatra, cours supérieur (13°59’S, 48°26’E), 650 m, 9.VI.2000 (fr.), Gautier et al. LG 3774 (K n.v., MO, P[P01954153]) ; Diana , Antsiranana II, Anjakely , Andrafiamena, Ampantsona Forest, 12°54’49”S, 49°17’24”E, 494 m, 18.VI.2007 (fr.), Letsara & Jaomora LRK 238 ( CAS) ; Diana Region , Ambilobe , Beramanja , Anketrabe Belinta, forêt de Galoko, 13°35’17”S, 48°42’49”E, 325 m, 2.X.2013 (fl.), Manjato et al. 433B ( OWU, P[P01060835]) ; Antsiranana (Diego Suarez) region , c. 80 road-km S of city, in Réserve spéciale Ankarana, 12°52’S, 49°14’E, 320 m, 23.XI.1989 (fl. buds), McPherson 14522 (K n.v., MO) ; Daraina , forêt de Bekaraoka, 13°06’38”S, 49°42’29”E, 261 m, 12.II.2004 (fr.), Nusbaumer & Ranirison LN 1160 (G, K n.v., P[P06774748]) ; Fiv. Ambanja , Fir. Ambodimanga-Ramena , Fkt. Antsahabe , Village Mandrizavona, rivière d’Antsahasoa, 13°47’31”S, 48°45’26”E, 460 m, 12.IV.2000 (fr.), Rabenantoandro et al. 166 (K n.v., MO, P[P01954146]) ; Antsiranana , Fiv. Ambanja , Domaine de Sambirano , village de Benavony , Bekaka, à 6 km au SE d’Ambanja, 13°43’32”S, 48°28’48”E, 80 m, 15.V.1988 (fr.), Randrianaivo et al. 233 ( MO, P[P01954147]) ; Daraina , forêt de Bekaraoka, partie nord, 13°07’03”S, 49°42’41”E, 360 m, 12.II.2004 (fr.), Ranirison & Nusbaumer PR 438 (G, K n. v., P[P06774747]) ; Marotongoza , district de Nossy Bé, 13.III.1957 (st.), Réserves Naturelles 9400 (B, K n.v., P[P01954151, P01954152]) ; Manisakaomby , Latsory , Ankaramy Canton, Analalava District, 14.V.1959 (st.), Service Forestier 32 33 R 362 (K, P[P01954148]) ; Ambanja , Béamfrangibé Marotovy, 16-30.III.1951 (fr.), Service Forestier 2958 SF (P[P01954150]) ; Benavony-Ambanja , 8.IV.1953 (fr.), Service Forestier 7247 (P[P02008537, P01954130, P01954131]) ; Station forestière de Sakaramy-Diego, 17.XII.1953 (fl. buds), Service Forestier 7962 (P[P02005956]) ; Forêt d’Ambre , Diégo, 18.VI.1954 (st.), Service Forestier 10284 (P[P02008536]) .

DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Xylopia ambanjensis is restricted to a small area of northern Madagascar, usually in dry deciduous forest but occasionally in humid evergreen

forest ( D’Amico & Gautier 2000), often on rocky or sandy sites, at elevations from 80 to 650 meters ( Fig. 28 ). Specimens with expanding flower buds have been collected in November and December, specimens with flowers in September and October, and specimens with fruits from January to June and in September. With an EOO and AOO of 5498 km 2 and 48 km 2, respectively, and documented from 12 localities, X. ambanjensis is given a preliminary conservation assessment of Endangered ( Table 2 ).

LOCAL NAMES. — Fotsiavadika (Andriamiarinoro et al. 369), hazoambo (Réserves Naturelles 9400, Service Forestier 2958 SF), mampahy (Gautier LG 3160), moranga (Randrianaivo et al. 233, Service Forestier 7247), morango (Antilahimena et al. 455).

DESCRIPTION

Tree up to 25 m tall, rarely a shrub; d.b.h. up to 20 cm.

Twigs sparsely appressed-pubescent, the hairs 0.1-0.3 mm long, soon glabrate; nodes with one or occasionally two axillary branches.

Leaves with larger blades 6.4-8.8 cm long, 1.5-2.2 cm wide, chartaceous, discolorous, greenish gray and shiny adaxially, brown and dull abaxially, narrowly lanceolate, apex gradually acuminate, the acumen 9-12 mm long, occasionally acute, base cuneate, short-decurrent on petiole, margin flat or slightly recurved, glabrous adaxially, finely appressed-pubescent but eventually glabrate abaxially; midrib darkening toward base adaxially, secondary veins brochidodromous, 13-17 per side, diverging at 45-70° from midrib, these and higher-order veins indistinct, plane adaxially, very slightly raised abaxially; petiole 3.8-6 mm long, shallowly canaliculate, faintly wrinkled, glabrate.

Inflorescences axillary, 1-8-flowered, the inflorescence axis sometimes becoming leafy, pedunculate or not, sparsely appressed-pubescent; peduncle 1-2.5 mm long, or absent; pedicels two per peduncle or arising separately from leaf axil, 4.2-6.4 mm long, 0.5-0.6 mm thick; bracts 2, spaced evenly along the length of the pedicel, caducous or distal bract often persistent, 1.1-1.7 mm long, ovate; buds lanceolate, apex obtuse.

Sepals slightly spreading at anthesis, 1/3-connate, 1.3-1.6 mm long, 1.9-2.3 mm wide, subcoriaceous, triangular to semicircular, apex acute to obtuse, appressed-pubescent abaxially.

Petals yellow-green, red at base in vivo; outer petals spreading at anthesis, 10.9-12.1 mm long, 1.9-2.1 mm wide at base, 1.0- 1.3 mm wide at midpoint, slightly fleshy, lanceolate, keeled at apex adaxally, keeled abaxially, apex obtuse, puberulent adaxially, appressed-pubescent abaxially; inner petals slightly spreading at anthesis, 8.4-8.8 mm long, 1.8-2.2 mm wide at base, 0.6-0.7 mm wide at midpoint, slightly fleshy, linearsubulate, keeled on apical ¼-1/2 adaxially, keeled abaxially, apex acute, base concave with undifferentiated margin and long claw, puberulent but becoming glabrous toward the base on both surfaces.

Stamens c. 100; fertile stamens 1.3-1.4 mm long, narrowly oblong, anther connective apex 0.2-0.4 mm long, shieldshaped, overhanging anther thecae, minutely papillate, anthers 14-16-locellate, filament 0.4-0.5 mm long; outer staminodes 1.3-1.4 mm long, oblong to clavate, apex obtuse to truncate; inner staminodes 0.8-1.0 mm long, oblong, apex rounded to truncate; staminal cone 1.2-1.4 mm in diameter, c. 0.8 mm high, concealing lower half of ovaries, rim irregularly laciniate.

Carpels c. 5; ovaries c. 1 mm long, oblong, pubescent, stigmas loosely connivent, c. 2.5 mm long, filiform, setose at apex.

Fruit of up to 5 monocarps borne on a pedicel 3.5-12 mm long, 1.5-4.5 mm thick, glabrate or with a few hairs; torus 3-8 mm in diameter, 2-6 mm high, globose to depressed-globose; monocarps with yellowish, greenish, or blackish red exterior and red endocarp in vivo, 2.3-3.1 cm long, 1.5-1.8 cm wide, 1.3-1.5 cm thick, oblong to obovoid, not torulose, apex rounded, base sessile or contracted into a stipe 2-3 mm long, 5-7 mm thick, finely verrucose, rugose, sparsely lenticellate, dull, frequently with a pronounced abaxial ridge, glabrate; pericarp 2-4 mm thick.

Seeds up to 6 per monocarp, in two rows, perpendicular to oblique to long axis, 9.9-11.6 mm long, 6.7-8.3 mm wide, 4-6.1 mm thick, broadly ellipsoid, elliptic, semicircular, or wedge-shaped in cross-section, brown, smooth, dull, perichalazal ring faintly or not evident; presence of sarcotesta not determined; aril absent.

NOTES

Xylopia ambanjensis is readily separated from most Madagascar Xylopia species by the narrow leaves with gradually acuminate apices. It is most similar to X. longirostra , sp. nov., but that species has leaves with a proportionately longer acumen and its monocarps are much larger and lenticellate. Xylopia ambanjensis also resembles X. lastelliana , but lacks the sericeous indument of the leaves and twigs and has smaller monocarps that are somewhat wrinkled but not strongly lenticellate. An odd characteristic of X. ambanjensis seen in several specimens is that one branch of the inflorescence may continue to grow out as a leafy shoot. The shoot is usually not persistent, but leaves a stub that remains visible on the pedicel of the fruit. Xylopia ambanjensis overlaps in distribution and habitat with several other northern dry forest species in Madagascar. The cuneate leaf base distinguishes it from X. bemarivensis , X. sahafariensis , and X. sericolampra , and the larger and gradually acuminate leaves distinguish it from X. sclerophylla , sp. nov. The specimen Service Forestier 5539 (P[P01989232]) from Sakaramy – Diego, 12.VIII.1952 (fr.), has twigs and foliage typical in appearance for X. ambanjensis , but the monocarps on the specimen are distinctly stipitate with strong oblique wrinkles, a fruit morphology that was not seen on any other specimens.

In the phylogenetic study of Stull et al. (2017) an accession of X. ambanjensis, Ammann et al. MYA 304, was part of a subclade with the Madagascar species X. buxifolia and X. lemurica , but with weak branch support. This subclade includes all Madagascar species known to have a green sarcotesta on the seed, but the label of Rabenantoandro et al. 166 describes the seed of X. ambanjensis as having an “arille de couleur rouge”. No aril was seen on the seeds of this species, however, so it is not possible to decide if the red color is a reference to the red endocarp in which the seeds are embedded, or to a sarcotesta.

Figures

FIG. 14. — Xylopia bemarivensis Diels, X. ambanjensis, and X. lastelliana Baill. A-K, X. bemarivensis: A, stamen, abaxial view; B, inner petal, adaxial surface; C, outer petal, adaxial surface; D, seed, side view; E, seed, view of micropylar end; F, habit; G, flower, side view; H, bud, side view with one outer petal removed to show inner petals; I, flower with petals, stamens, and stigmas removed to show staminal cone; J, fruit; K, leaf. L-P, X. ambanjensis: L, inflorescence; M, fruit; N, leaves; O, seed, side view; P, seed, view from micropylar end. Q-Y, X. lastelliana: Q, stamen, abaxial view; R, outer staminode, abaxial view; S, T, inner petals adaxial surface; U, outer petal, adaxial surface; V, flower with petals and stamens removed to show stigmas and staminal cone; W, leaf base abaxial surface,

FIG. 28. — Distributions of Xylopia ambanjensis Cavaco & Keraudren, X. anomala, sp. nov., X. australis, sp.nov., X.beananensis Cavaco & Keraudren, X. bemarivensis Diels,X.buxifolia Baill., X.capuronii Cavaco & Keraudren,X. carinata, sp. nov., X. danguyella Ghesq. ex Cavaco & Keraudren, X. dielsii Cavaco & Keraudren, X. fananehanensis Cavaco & Keraudren, and X. flexuosa Diels on Madagascar.