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
7.
Xylopia ravelonarivoi
D.M.Johnson & N.A.Murray
,
sp. nov.
(
Figs 6B
;
11
)
Species resembling
Xylopia humblotiana
Baill.
in its small blunt coriaceous leaves, obtuse petals, and narrowly oblong monocarps, but differing in the tree habit, more strongly decurrent leaf bases, densely pubescent pedicels and sepals, lanceolate outer petals, and more strongly wrinkled monocarps borne on pedicels
13-19 mm
long and
1.6-3.7 mm
thick.
TYPE. —
Madagascar
.
Prov. Toamasina
,
Antsimanana Region
:
Brickaville
,
Maroseranana
,
Ambodilendemy
,
suivant la rivière d’Andrangato
,
18°26’05”S
,
48°46’51”E
,
658 m
,
14.III.2011
(fl.),
Ravelonarivo et al. 3641
(holo-,
MO
!).
PARATYPES
. —
Madagascar
.
Prov.
Antsiranana
,
Sava Region
,
Diego
,
Sambava
,
Anjangoveratra
,
Anamboafo
, forêt
de Makirovana-Beraharaha
,
14°09’07”S
,
49°57’13”E
,
549 m
,
6.III.2014
(fl.),
Martial
et al. 548
(
MO
)
;
Sava Region
,
Sambava
,
Anjangoveratra
,
Anamboafo
, forêt
de Belalitra
,
Makirovana
,
14°09’14”S
,
49°58’09”E
,
585 m
,
8.III.2014
(fl.),
Rakotonirina
et al. 537
(
MO
)
;
Marojejy
RNI,
Analamboahangy
,
Andrakata
,
Andapa
, aux environs
de Manenobasy
,
14°35’16”S
,
49°41’20”E
,
1171 m
,
18-24.I.1995
(fr.),
Rasoavimbahoaka
509
(
MO
, P[P01954048])
;
Andrakata Canton
,
Andapa District
[
14°37’S
,
49°43’E
],
13.VIII.1957
(fr.),
Safy
9089 RN
(P[P01954046])
.
Prov.
Mahajanga
,
Ruisseau Ambatoharanana Andranomena
commune rurale de Matsoandakana
,
district de Befandrina Nord
,
15°08’16”S
,
49°21’02”E
,
1045 m
,
12.II.2008
(fr.),
Bernard et al. 778
(
K
,
MO
).
Prov. Toamasina
,
Fivondronana Maroantsetra
,
Commune Ambinanitelo
,
Fokontany Marovovonana
,
Ankiriandro Mountain
,
15°17’37”S
,
49°33’10”E
,
640 m
,
10.I.2003
(fr.),
Antilahimena et al. 1683
(
K
,
P
[
P01954047
])
;
Analanjirofo Region
, Fivondronana Vavatenina, Commune Ambodimangavalo, à
3 km
à l’Ouest du village Ambatoharanana, dans
le Parc
national
de Zahamena
, le long de la piste vers Antevibe,
17°33’54”S
,
48°53’18”E
,
875 m
,
29.IV.2003
(fr.),
Rakotonandrasana 676
(
OWU
)
;
Toamasina
sous-préfecture, Vavatenina, commune: Ambodimangavelo, Moango, dans l’Aire protégée
de Zahamena
,
17°33’32”S
,
48°53’55”E
,
800 m
,
4.V.2003
(immature fr.),
Rakotondrajaona et al. 281
(K,
MO
)
;
Antsinanana Region
, Vohimanana, Dist. Brickaville, Com. Maroseranana, Fkt. Ambatolampy,
18°23’27”S
,
48°48’11”E
,
846 m
,
23.I.2012
(fr.),
Ravelonarivo et al. 4171
(
MO
)
.
DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. —
Xylopia ravelonarivoi
,
sp. nov.
, occurs in humid lowland and lower montane forest on ridges and slopes in northeastern
Madagascar
at elevations from 549 to 1171 meters.Specimens have been collected with flowers in March and with fruits in January, February, April, and May. With an EOO and AOO estimated as
7118 km
2
and
40 km
2
, respectively, the species is given a preliminary conservation assessment of Endangered. It is documented by two collections from within the protected area of Zahamena National Park and one collection from the Marojejy Reserve.
LOCAL NAMES. — Hazoambo (
Rakotondrajaona et al. 281
), hazoambo boriboriravina (
Rakotonandrasana 676
), moranga (
Martial et al. 548
), morango (
Rakotonirina et al. 537
).
DESCRIPTION
Tree
up to
15 m
tall, or rarely a shrub up to
8 m
; d.b.h. up to
30 cm
.
Twigs
densely appressed-pubescent, the hairs
0.1-0.3 mm
long, eventually glabrate; nodes with one axillary branch.
Leaves
with larger blades 5.0-
7.2 cm
long, 2.0-
3.4 cm
wide, subcoriaceous to coriaceous, discolorous, dark brown to gray and often shiny adaxially, light brown and dull abaxially, obovate, oblanceolate, elliptic, or elliptic-oblong, apex obtuse, rounded, retuse, or emarginate, base cuneate, decurrent on petiole, margin slightly recurved or revolute, glabrous adaxially, sparsely appressed-pubescent, especially along midrib, abaxially; midrib dull red to brown, darkening toward base adaxially, secondary veins weakly brochidodromous, 8-11 per side, diverging at 50-70° from midrib, these and higherorder veins raised and forming a conspicuous reticulum on both surfaces; petiole
1.5-7 mm
long, shallowly canaliculate or a little flattened, smooth or faintly wrinkled, glabrous or with a few hairs.
Inflorescences
axillary from the axils of fallen leaves, 1-3-flowered, pedunculate, densely appressed-pubescent; peduncle
1.7-1.8 mm
long; pedicels up to 3 per peduncle,
4.8-9.7 mm
long, 1.0-
1.2 mm
thick; bracts 2, one near base of the pedicel and the other near midpoint, caducous, only scars seen; buds lanceolate, apex obtuse.
Sepals
spreading at anthesis, ¼-1/2-connate,
1.4-3.6 mm
long,
3.5-4 mm
wide, coriaceous, broadly triangular, apex acute or rarely obtuse, appressed-pubescent abaxially.
Petals
greenish white
in vivo
; outer petals slightly spreading at anthesis, 10.0-
12.2 mm
long,
2.7-4.5 mm
wide at base, 2.4-3.0 mm wide at midpoint, fleshy, lanceolate, keeled at the apex but otherwise flat adaxially, flat abaxially, apex obtuse, densely pubescent except for glabrous base adaxially, densely appressed-pubescent abaxially; inner petals slightly spreading at anthesis,
10.5-10.9 mm
long, 2.2-3.0 mm wide at base,
0.9-1.2 mm
wide at midpoint, fleshy, linear-subulate, keeled on both surfaces, apex acute, concave with undifferentiated margin, densely pubescent on both surfaces except for glabrous base, with a band of papillae across widest point adaxially.
FIG. 11. —
Xylopia ravelonarivoi
,
sp. nov.
:
A
, habit;
B
, leaf base,oblique adaxial view to show decurrence of leaf blade on petiole;
C
, flower bud, side view;
D
, leaf;
E
, fruit;
F
, fertile stamen, abaxial view;
G
, outer staminode, abaxial view;
H
, adaxial staminode, abaxial view;
I
, outer petal, adaxial view;
J
, inner petal, adaxial view;
K
, seed, side view;
L
, seed, view of micropylar end.
A
, from
Rakotondrajaona et al. 281
(MO);
B
,
D
,
E
,
K
,
L
, from
Ravelonarivo et al. 4171
(MO);
C
,
F -J
, from
Ravelonarivo et al. 3641
(MO). Scale bars: A, D, E, 1 cm; B, C, I-L, 5 mm; F-H, 1 mm.
Stamens
c.
250; fertile stamens
1.1-1.4 mm
long, narrowly oblong, anther connective apex
0.2-0.3 mm
long, shield-shaped to capitate, overhanging anther thecae, minutely papillate, anthers 7-9-locellate, filament
0.4-0.6 mm
long; outer staminodes
c.
1.3 mm
long, oblong to clavate, apex truncate or rounded; inner staminodes 1.0-
1.1 mm
long, clavate, apex truncate; staminal cone
2.2-2.6 mm
in diameter, 1.0-
1.5 mm
high, completely concealing the ovaries, rim even.
Carpels
10-13; ovaries 1.0-
1.1 mm
long, narrowly oblong, pubescent, stigmas connivent,
1.8-2.2 mm
long, filiform, glabrous or with a few apical hairs.
Fruit
of up to 13 monocarps borne on a pedicel
13-19 mm
long,
1.6-3.7 mm
thick, glabrate or with a few scattered hairs; torus
5-12 mm
in diameter,
3.5-9 mm
high, depressed-globose; monocarps with red exterior
in vivo
,
2.2-4.5 cm
long,
0.5-0.9 cm
wide,
0.5-0.8 cm
thick, narrowly oblong, often slightly torulose, apex obtuse to rounded, sometimes slightly beaked, base tapered gradually, sometimes forming a stipe
c.
4 mm
long,
3 mm
thick, obliquely wrinkled, shiny, glabrate; pericarp
0.3-0.8 mm
thick.
Seeds
up to 5 per monocarp, in a single row, nearly parallel to long axis,
5.6-7.8 mm
long,
2.9-4.6 mm
wide, 3.3-4.0 mm thick, broadly ellipsoid to oblong, elliptic in cross-section, dark brown to black, smooth or slightly wrinkled and pitted, shiny, perichalazal ring slightly raised; sarcotesta absent; aril white
in vivo
, white to amber-colored when dried, bilobed, lobes 2.0-
2.5 mm
long, 3.0-
3.6 mm
wide, fleshy, surface wrinkled.
NOTES
Xylopia ravelonarivoi
,
sp. nov.
, is similar to
X. humblotiana
but differs in a number of characters that, together with the ecological differences, distinguish the two species. It is usually a tree up to
15 m
tall, rather than a shrub or treelet. The leaves have a more decurrent base, such that the demarcation between blade and petiole is indistinct (
Fig. 11B
). The pedicels and sepals are densely pubescent. The sepals are longer, and the outer petals are lanceolate rather than oblong; the latter character is also expressed in the buds that are lanceolate rather than oblong as in
X. humblotiana
. The monocarps of this species are obliquely wrinkled, while those of
X. humblotiana
are usually smooth. There is a sharp difference in elevation range between the two species:
X. ravelonarivoi
,
sp. nov.
, grows at elevations from
550 to 1170 m
and
X. humblotiana
from sea level to
50 m
.
Xylopia madagascariensis
also has monocarp and leaf sizes similar to those of
X. ravelonarivoi
,
sp. nov.
, but its leaves are blunt- acuminate rather than obtuse to rounded and its monocarps are smooth and finely verrucose rather than strongly wrinkled. In addition,
X. madagascariensis
reaches its upper elevational limit at just over 500 meters, while the lower elevational limit for
X. ravelonarivoi
,
sp. nov.
, is
c.
550 meters.
The specimen
Rakotondrajaona et al. 281
was the source of molecular data used in the phylogenetic analysis of
Xylopia
by
Stull
et al.
(2017)
, where it was identified as
X. humblotiana
; the seed illustrated in
Figure 4H
of that work is, however, correctly identified as
X. humblotiana
.
The species is named for Désiré Ravelonarivo, the collector of the
type
specimen, who has contributed to a clearer understanding of
Xylopia
diversity on
Madagascar
by making 16 critical
Xylopia
collections representing six species.