A revision of Xylopia L. (Annonaceae): the species of Madagascar and the Mascarene islands
Author
Johnson, David M.
Author
Murray, Nancy A.
text
Adansonia
2020
2020-02-05
42
1
1
88
journal article
21758
10.5252/adansonia2020v42a1
28f94b79-38d7-4c25-ac76-cf64809114fc
1639-4798
3877215
6.
Xylopia madagascariensis
Cavaco & Keraudren
(
Fig. 9A-F
)
Bulletin de la Société botanique de France
103: 276 (1956).
—
Type
:
Madagascar
. Prov.
Toamasina
[“Domaine
de l’Est
”],
Vohimarangitra
, environs
de Tamatave
[=
Betampona
,
17°55’S
,
49°13’E
],
22.II.1950
(fl.),
Réserves Naturelles de Madagascar
2440
(holo-, P[P030410]!;
iso-, K[K000199049]!, P[P030411, P030412]!).
MATERIAL EXAMINED. —
Madagascar
.
Prov
.
Antsiranana
.
Sava Region, Sambava, Anjangoveratra, forêt de Tsihomanaomby,
14°06’S
,
50°02’E
,
17.II.2013
(fl. buds, fr.),
Martial et al. 34
(
MO
,
OWU
).
Prov.
Toamasina
. Canton Ambodiriana,Tamatave District,
9.II.1962
(fr.),
Momohizaza 11999 RN
(P[P01987141]); R. N. I. Tamatave,
24.III.1951
(fr.),
Rakotoniama 2861 RN
(P[P01987142, P01987143]);
Antsinanana
,
District
Toamasina
II,
Commune Rurale Sahambala
,
Fokontany Sahavongo
, village le plus proche
Sahavongo
,
Iambeau
de forêt
d’Ambavadilagna
,
18°01’16”S
,
49°05’42”E
,
529 m
,
5.II.2017
(fl., fr.),
Ralaijaona
et al. 74
(
MO
)
;
Masoala Peninsula
, flat coastal sand forest just N of
Tampolo
, approximately
11 km
S of Ambanizana
,
15°43’S
,
49°57-58’E
,
0-5 m
,
26.XII.1990
(fl., fr.),
Schatz
&
Modeste
3095
(G, K n.v.,
MO
, P[P01954052],
WAG
)
;
Faranharoina-Maroantsetra
,
8.III.1955
(fr.),
Service Forestier
12977
(
BR
, K n.v., P[P06901365])
.
DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. —
Xylopia madagascariensis
occurs in eastern
Madagascar
, in humid forest near the coast, at elevations from 0-5 meters up to
529 m
(
Fig. 29
). The specimens with flowers were collected in February and December, and with fruits in February, March, and December. With an EOO and AOO estimated as
3780 km
2
and
24 km
2
, respectively, the species is given a preliminary conservation assessment of Endangered.
LOCAL NAMES. — Hazoambo (
Momohizaza 11999 RN, Ralaijaona et al. 74
), hazoambolahy (
Rakotoniama 2861 RN
), moranga (
Martial et al. 34
).
DESCRIPTION
Tree
up to
16 m
tall; d.b.h. up to
28 cm
.
Twigs
sparsely appressed-pubescent, the hairs
0.1-0.4 mm
long, becoming glabrate; nodes with a single axillary branch.
Leaves
with larger blades
5.2-6.6 cm
long,
1.8-2.7 cm
wide, subcoriaceous, slightly discolorous, dull gray to gray-green adaxially, tan to reddish brown abaxially, lanceolate to elliptic, apex blunt-acuminate, the acumen
4.5-11 mm
long, base broadly cuneate, short-decurrent on petiole, margins flat or slightly revolute, glabrous adaxially, sparsely sericeous abaxially; midrib red toward the base adaxially, secondary veins brochidodromous, 11-13 per side, diverging at 60- 70° from midrib, these and higher-order veins raised and forming a conspicuous reticulum on both surfaces; petiole
3.3-6 mm
long, semi-terete, transversely and longitudinally wrinkled, glabrous to sparsely pubescent.
Inflorescences
axillary or from the axils of fallen leaves, 2-4-flowered, pedunculate, appressed-pubescent; peduncle
1.8-2.2 mm
long; pedicels 2-4 per peduncle,
5.5-9 mm
long, 0.8-1.0 mm thick; bracts 2-3, attached proximal to the pedicel midpoint, caducous,
0.5-0.7 mm
long, semicircular; buds narrowly oblong, apex obtuse.
Sepals
slightly spreading at anthesis, 1/2-connate,
2.3-2.5 mm
long, 4.0-
4.3 mm
wide, coriaceous, semicircular, apex broadly acute to rounded, appressed-pubescent abaxially.
Petals
dull yellow to orange, with the outer petals whitish at the base and the inner petals red-tinted at the base
in vivo
; outer petals spreading at anthesis,
16-18 mm
long,
3.5-3.9 mm
wide at base,
2.3-2.8 mm
wide at midpoint, coriaceous to slightly fleshy, narrowly oblong, flat, apex obtuse, appressed-pubescent except for the glabrous base adaxially, velutinous abaxially; inner petals possibly erect and somewhat connivent at anthesis,
14-20 mm
long, 2.9-3.0 mm wide at base,
0.8-1.1 mm
wide at midpoint, fleshy, linear, laterally compressed, weakly keeled on upper ¾ adaxially, strongly keeled abaxially, apex obtuse to acute, base concave with undifferentiated margin, densely puberulent except for glabrous base on both surfaces.
Stamens
c.
140; fertile stamens
1.2-1.6 mm
long, narrowly oblong, anther connective apex
0.1-0.2 mm
long, shield-shaped, overhanging anther thecae, papillate, anthers 9-14-locellate, filament
0.5-0.6 mm
long; outer staminodes
c.
1.5 mm
long, clavate, apex rounded; inner staminodes
c.
1 mm
long, clavate, apex truncate; staminal cone 2.0-
2.6 mm
in diameter, 1.0-
1.4 mm
high, completely concealing the ovaries, rim even.
Carpels
c.
15; ovaries
c.
1 mm
long, narrowly oblong, sericeous, stigmas connivent,
2.2-2.9 mm
long, filiform, smooth, glabrous.
Fruit
of up to 10 monocarps, borne on a pedicel
8-14 mm
long, 2.0-
3.5 mm
thick, glabrate; torus 4.7-8.0 mm in diameter,
3.5-5.5 mm
high, depressed-globose to globose; monocarps with red exterior and red endocarp
in vivo
,
2-3.7 cm
long,
0.8-1.1 cm
wide,
0.7-0.8 cm
thick, oblong to narrowly cylindrical, not torulose, apex rounded or obtuse, base sessile or contracted into a stipe
2-3 mm
long,
c.
3 mm
thick, verrucose, smooth or faintly wrinkled, glabrate or bearing a few sparse hairs; pericarp
c.
1.5 mm
thick.
Seeds
up to 3 per monocarp, in a single row, oblique or perpendicular to long axis,
6-8.6 mm
long,
4.2-4.6 mm
wide,
c.
3.8 mm
thick, oblong, broadly elliptic in cross-section, black, smooth, shiny, perichalazal ring slightly raised; sarcotesta absent; aril white
in vivo
, whitish orange to dull orange when dried, bilobed, lobes
c.
2.2 mm
long,
3-3.4 mm
wide, papery, smooth to somewhat wrinkled.
NOTES
Xylopia madagascariensis
is very similar to
X. humblotiana
, but differs consistently in the proportionally narrower leaves that are acuminate rather than obtuse to rounded. In addition, its leaves are sparsely appressed-pubescent abaxially rather than glabrous. In the limited sample available, the inner petals are wider at the base and narrower at the midpoint than in
X. humblotiana
. The monocarps average smaller with fewer seeds, which are oblique to perpendicular to the long axis of the monocarp rather than parallel. Although little habitat information is given on the labels for any of the specimens of
X. madagascariensis
, it seems to frequent a wider range of forest habitats and elevations than the littoral forests on sand where
X. humblotiana
occurs. The specimen
Randriatafika 16
(MO), from Fianarantsoa Province (forêt dense humide de l’Est d’Andranobetokana, Ampasimadinika, Marofototra, Mananjary,
20°49’51”S
,
48°05’00”E
,
16-21.I.1999
[fl.]) resembles
X. madagascariensis
, but the bracts and pedicels are less pubescent and the petals shorter (but only large buds on the specimen). It was collected to the south of the main range of
X. madagascariensis
, and additional collections from the area would be helpful in determining its status.