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
10.
Xylopia sericolampra
Diels
(
Figs 6H
;
13
)
Notizblatt des Botanischen Gartens und Museums zu Berlin-Dahlem
9: 353 (1925).
—
Type
:
Madagascar
. Prov.
Mahajanga
[“Madagascaria occidentalis”],
Boina
,
Bongolava
, in silvis sabulosis aridis,
X.1907
(fl.),
Perrier de la Bâthie
4966
(holo-, B!;
iso-, P[P030425, P00364248]!).
MATERIAL EXAMINED. —
Madagascar
. Prov.
Mahajanga
. Canton Tsaramandroso, District A[mba]to Boina, Antongomlilanivy de Ankarafantsika,
5.X.1948
(fl.),
Réserves Naturelles
[
Ramamanjisoa
]
1665 RN
(K n.v.,
OWU
, P[P01953995, P01953996, P02133042]);
R. N. 7, Canton Tsaramandroso, District Ambato-Boeni,
10.XI.1952
(fl.),
Ramamanjisoa 4737 RN
(K, P[P01953991, P01953992, P02133041]);
Ampijoroa, Ankarafantsika, J. Botanique, on gentle slope
1 mi
from lake,
26.VII.1970
(buds),
Richard 429
(K); Without definite locality, s. d. (fr.),
Service Forestier 114 SF
(P[P00524384, P01953990]).
DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. —
Xylopia sericolampra
is known only from a small area of dry forest on sand in northwestern
Madagascar
(
Fig. 30
). Specimens with flowers have been collected in October and November; the one specimen with fruits is undated. Several iNaturalist postings from the vicinity of Sofia show new flushes of leafy shoots and flowers appearing in late September and November, and an apparently mature fruit in January (
Fig. 6H
). In the September photographs the leaves of the previous growing season are still present, but in the November photographs they have been shed from the plant. With an EOO and AOO estimated as
859 km
2
and
20 km
2
, respectively, it is given a preliminary conservation assessment of Endangered (
Table 2
).
LOCAL NAME. — Lompingo (
Réserves Naturelles
[
Ramamanjisoa
]
1665 RN
). According to
Baron (1890)
, this name is also given to a species of
Diospyros
.
FIG. 12. —
Xylopia sahafariensis
Cavaco & Keraudren:
A
, outer petal, adaxial surface;
B
, inner petal, adaxial surface;
C
, inflorescences;
D
, flower with petals and stamens removed to show staminal cone and carpels;
E
,
F
, stamens, abaxial view;
G
, habit. All from
Ratovoson et al. 1067
(MO). Scale bars: A, B, D, 1 mm; C, 2 mm; E, F, 0.5 mm; G, 1 cm.
DESCRIPTION
Shrub
up to
4 m
tall.
Twigs
short silvery appressed-pubescent, the hairs
0.1-0.2 mm
long, eventually glabrate; nodes with one axillary branch.
Leaves
with larger blades
4.7-7.2 cm
long, 2.0-3.0 cm wide, subcoriaceous, discolorous, gray to brown and shiny adaxially, dull grayish tan abaxially, oblanceolate to narrowly elliptic, apex obtuse to rounded, sometimes slightly emarginate, base truncate or sometimes rounded, margin flat to slightly revolute, glabrous adaxially, sparsely and finely appressed-pubescent abaxially; midrib pinkish brown toward the base adaxially, secondary veins weakly brochidodromous, 9-14 per side, diverging at 45-60° from midrib, these and higher-order veins plane and indistinct on both surfaces; petiole
1.8-3.5 mm
long, semi-terete, longitudinally wrinkled, glabrate or with a few sparse hairs.
Inflorescences
arising from axils of the first 3-4 bracts of newly expanding shoots, 1-flowered, not pedunculate, densely sericeous; pedicels
1.7-3.2 mm
long,
c.
1.0 mm thick; bracts 3-4, evenly spaced on pedicel, proximal bracts usually caducous,
distal bract
2.3-4 mm
long, orbicular to reniform; buds lanceolate, apex obtuse, sometimes slightly falciform.
Sepals
slightly spreading at anthesis, ¼-¾-connate, 3.0-
4.2 mm
long,
2.9-4 mm
wide, coriaceous, broadly ovate, apex acute or apiculate, densely sericeous abaxially.
Petals
yellow
in vivo
; outer petals spreading at anthesis,
13.9- 17.4 mm
long,
2.4-2.9 mm
wide at base, 1.0-
1.6 mm
wide at midpoint, coriaceous, linear-lanceolate, flat, apex acute, densely puberulent except at base adaxially, densely sericeous abaxially; inner petals more or less spreading at anthesis,
10- 15.8 mm
long,
1.5-2.2 mm
wide at base,
0.7-0.8 mm
wide at midpoint, slightly fleshy, linear, faintly keeled on both surfaces, apex acute, base concave with undifferentiated margin, thinly puberulent except at base adaxially, more densely puberulent but sparse toward base abaxially.
Stamens
c.
100; fertile stamens
1.2-1.3 mm
long, narrowly oblong, anther connective apex
c.
0.1 mm
long, conical or slightly bifid, rudimentary, not overhanging anther thecae, glabrous, anthers
c.
10-locellate, filament
0.5-0.6 mm
long; outer stami- nodes (loose in packet)
c.
1.4 mm
long, clavate, apex obtuse; inner staminodes (loose in packet)
c.
1.0 mm long, oblong, apex obliquely truncate; staminal cone rudimentary or absent.
Carpel
1,
c.
1.7 mm
long, lanceolate; ovary and stigma continuous, apex obtuse, pilose.
Fruit
a single monocarp borne on a pedicel
3 mm
long,
3.5 mm
thick, pubescent; torus
c.
4.2 mm
in diameter, not expanded; monocarp with peach-colored exterior
in vivo
,
2.5-4.8 cm
long, 2.0-
2.5 cm
wide,
1.9-2.5 cm
thick, pyriform, oblong, or ovoid, not torulose, apex rounded, base sessile, rounded or slightly tapered, smooth or slightly wrinkled, surface marked by a pattern of raised longitudinal veins, pubescent; pericarp
c.
3.4 mm
thick.
Seeds
c.
3 per monocarp, in a single row, lying perpendicular to long axis,
c.
15.4 mm
long,
12-13.9 mm
wide,
8.8-9 mm
thick, ellipsoid, irregularly elliptic in cross-section, light brown, smooth, dull, perichalazal ring not elevated; sarcotesta presence or absence undeterminable; aril absent, micropylar end of seed marked by a light brown smooth area.
NOTES
Xylopia sericolampra
is distinguished from other
Madagascar
species by the combination of silvery indument of the new shoots and inflorescences, the shiny leaves with blunt apices and truncate bases, and the remarkable single ovoid monocarp with raised venation on its surface. The raised monocarp venation is shared with
X. mwasumbii
of coastal
Tanzania
, but the latter has flattened rather than ovoid monocarps.
Xylopia sericolampra
differs from the second
Madagascar
species of section
Verdcourtia
,
X. sahafariensis
, the fruits of which are unknown, by its longer and narrower petals, truncate leaf bases, and indument of silver hairs on the young growth. Its inflorescences appear with the expansion of the new vegetative shoots, which are enclosed by overlapping conduplicate leaves. The label of the
type
specimen reports the bark to be black.