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
32.
Xylopia retusa
D.M.Johnson & N.A.Murray
,
sp. nov.
(
Figs 2A
;
27L-R
)
Xylopia
species resembling
X. buxifolia
in the small leaves having retuse to emarginate apices, but differing in the leaves proportionally narrower, 0.6-1.1 versus
1.2-2.7 cm
wide, the densely sericeous petals with the apices of the inner petals strongly bent outward at anthesis, the stigmas
c.
0.8 mm
long and oblong versus
1.9-3.3 mm
long and filiform, the monocarps
3.2 cm
long or shorter that are obliquely wrinkled and have a broad beak at the apex, and the orange sarcotesta of the seeds.
TYPE. —
Madagascar
.
Prov. Toamasina
,
Fivondronana Sainte Marie
,
Firaisana Lokintsy
,
Fokontany Ambohidena
,
16°51’11”S
,
49°57’18”E
,
18.II.2004
(fl.),
Rabevohitra
et al. 5073
(holo-,
MO
!;
iso-, OWU!).
PARATYPES
. —
Madagascar
. Prov.
Toamasina
,
Antsinanana Region
,
Mahavelona Foulpointe
, sur la piste des lémuriens,
17°42’21”S
,
49°27’21”E
,
72 m
,
8.X.2011
(fr.),
Andriamiarinoro
&
Amosa
256
(
MO
, P[P01197860])
;
Est
: forêt sublittorale, sur sables, à
Ambila-Lemaitso
,
14.XII.1967
(fr.),
Capuron
28028 SF
(K,
OWU
)
;
Est
: partie méridionale de la forêt
de Vohibola
(
Tampina
), au lieu-dit
Ankany
ny nofy,
17.XII.1967
(fr.),
Capuron
28060_SF
(
AAU
, B)
;
Pref. Brickaville
,
Com. Amboniaonana
,
Fok. Andranokoditra
, 18°35’53”-
18°34’20”S
, 49°14’42”-
49°14’54”E
,
53 m
,
7.I.2003
(fr.),
Ludovic
&
Rakotoarivony
212
(
MO
,
OWU
)
;
Fivondronana
:
Brickaville
,
Firaisana
:
Ambinaninony
,
Fokontany
:
Andranonkoditra
, forêt littorale sur sable du label
Conservation Biodiversité Développements
(
CBD
) à
Vohibola
,
18°34’50”S
,
49°15’16”E
,
10 m
,
8.XII.2001
(fr.),
Rabenantoandro
et al. 855
(
MO
[2 sheets])
;
Fivondronana Brickaville
,
Firaisana Ambinaninony
,
Fokontany Andranokoditra
,
18°35’32”S
,
49°14’02”E
,
5 m
,
11.II.2003
(fr.),
Rabenantoandro
et al. 1244
(
MO
,
OWU
, P[P01986994])
;
Fivondronana Brickaville
,
Firaisana Ambinaninony
,
Fokontany Andranokoditra
,
18°35’32”S
,
49°14’02”E
,
5 m
,
11.II.2003
(fr.),
Rabenantoandro
et al. 1249
(K,
MO
,
OWU
, P[P01986991])
;
Toamasina District
,
Analalava forest
, far southwest corner of the forest occurring north of the road from
Foulpointe
to
Sahamamy
,
17°42’28”S
,
49°27’04”E
,
17.VI.2005
(fr.),
Skema
et al. 73
(
MO
)
.
DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. —
Xylopia retusa
,
sp. nov.
, is restricted to central-eastern
Madagascar
, in littoral forests on sandy soil near the coast at elevations from sea level up to 70 meters (
Fig. 30
).The specimen with flowers was collected in February, those with fruits have been collected in January, February, June, October, and December.
Xylopia retusa
,
sp. nov.
, was estimated to have an EOO of
1751 km
2 and an AOO of
32 km
2
, and is given a preliminary conservation assessment of Endangered (
Table 2
).
LOCAL NAME. — Hazoambo (
Andriamiarinoro & Amosa 256, Skema et al. 73
).
DESCRIPTION
Tree
up to
12 m
tall; d.b.h. up to
18 cm
.
Twigs
finely pubescent, the hairs
0.1-0.2 mm
long, soon glabrate; nodes with one or often two axillary branches.
Leaves
with larger blades
2.4-3.6 cm
long,
0.6-1.1 cm
wide, chartaceous to subcoriaceous, slightly discolorous, pale graygreen adaxially, dull brown abaxially, elliptic, narrowly oblong, oblanceolate, or linear-lanceolate, apex rounded and retuse to emarginate, base cuneate, short-decurrent on petiole, margin slightly revolute, glabrous adaxially, sparsely appressed-pubescent abaxially, a tuft of hairs often visible in the apical notch; midrib concolorous with blade adaxially, secondary veins weakly brochidodromous, 9-11 per side, diverging at 50-70° from midrib, these and higher-order veins indistinct to slightly raised
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.
on both surfaces; petiole
0.8-2 mm
long, semi-terete, smooth, with a few scattered hairs.
Inflorescences
axillary, 1-flowered, not pedunculate, pubescent; pedicels
5-6.3 mm
long,
0.5-0.7 mm
thick; bracts 3,
one attached just distal to the pedicel base and the other 2 on the distal 1/3 of the pedicel, caducous or sometimes persistent,
1-1.5 mm
long, semicircular to triangular; buds lanceolate, apex obtuse.
Sepals
slightly spreading at anthesis, ¹⁄5-1/2-connate,
1.6- 2.4 mm
long, 2.0-
2.2 mm
wide, coriaceous, broadly ovate, triangular, or semicircular, apex obtuse to rounded, appressedpubescent abaxially.
Petals
yellow to yellowish orange
in vivo
; outer petals erect at anthesis,
9.3-11.4 mm
long,
1.7-2.2 mm
wide at base, 0.7- 1.0 mm wide at midpoint, coriaceous, linear, keeled from midpoint to apex adaxially, keeled abaxially, apex obtuse, densely puberulent except for the glabrous base adaxially, sericeous abaxially; inner petals erect with the apices sharply bent outward at anthesis, 6.0-
7.5 mm
long,
1.9-2.6 mm
wide at base,
0.5-0.7 mm
wide at midpoint, coriaceous, long-subulate, keeled adaxially except for concave base, slightly keeled abaxially, apex acute, base concave with undifferentiated margin but transversely thickened at the widest point, puberulent on both surfaces except for the glabrous base.
Stamens
c.
120; fertile stamens
0.8-1.1 mm
long, narrowly oblong, anther connective apex
0.1-0.2 mm
long, capitate to depressed-globose, overhanging anther thecae, papillate, anthers 7-8-locellate, filament
0.2-0.3 mm
long; outer staminodes
c.
1.0 mm long, clavate, apex obliquely truncate; inner staminodes
c.
1.0 mm long, clavate, apex truncate-emarginate; staminal cone
1.2-1.4 mm
in diameter,
0.4-0.5 mm
high, completely concealing the ovaries, rim even.
Carpels 2-3; ovaries
0.
4-0.5 mm long, oblong, pubescent, stigmas connivent,
c.
0.8 mm
long, narrowly oblong, glabrous or with a few hairs.
Fruit
of up to 5 monocarps borne on a pedicel
8-12 mm
long,
3-3.5 mm
thick, glabrate; torus
5.5-8 mm
in diameter,
5.7- 7 mm
high, depressed-globose to globose; monocarps with greenish red exterior and red endocarp
in vivo
,
2.4-3.2 cm
long,
1.2-1.6 cm
wide,
1.2-1.5 cm
thick, oblong, sometimes slightly torulose, apex rounded to a broad beak
1-2 mm
long, base contracted into a stipe
1-4 mm
long,
4-5 mm
thick, verrucose, obliquely wrinkled, usually with a prominent longitudinal ridge abaxially, dull, glabrate; pericarp
c.
1 mm
thick.
Seeds
up to 4 per monocarp, in a single row, perpendicular to long axis,
10-11.7 mm
long,
7.9-8.7 mm
wide, 4.8-7.0 mm thick, ellipsoid to broadly ellipsoid, flattened-elliptic or semicircular in cross-section, light brown, smooth, dull, perichalazal ring not evident; sarcotesta orange
in vivo
; aril absent.
NOTES
The small leaves of
X. retusa
,
sp. nov.
, which are retuse to emarginate at the apex, resemble those of
X. buxifolia
, which occurs in some of the same habitats and localities. This appears to represent a convergence, as
X. retusa
,
sp. nov.
, by virtue of its pubescent petals with the apices of the inner petals bent strongly outward and the orange sarcotesta of the seeds, most closely resembles
X. arenaria
of eastern Africa. Additional features of
X. retusa
,
sp. nov.
, distinguishing it from
X. buxifolia
include the narrowness of the leaves, the outer petals densely sericeous rather than sparsely so (and not turning black when dried), and the smaller and somewhat beaked monocarps usually marked by strong oblique wrinkles on the surface. The short stigmas that barely exceed the tops of the stamens are also unusual.