Three Critically Endangered new species of Capurodendron (Sapotaceae) from Madagascar
Author
Gautier, Laurent
Conservatoire et Jardin botaniques de la Ville de Genève and Laboratoire de botanique systématique et biodiversité de l’Université de Genève, C. P. 71, 1292 Chambésy, Switzerland
laurent.gautier@ville-ge.ch
Author
Naciri, Yamama
Conservatoire et Jardin botaniques de la Ville de Genève and Laboratoire de botanique systématique et biodiversité de l’Université de Genève, C. P. 71, 1292 Chambésy, Switzerland
text
Candollea
2018
2018-06-25
73
1
121
129
journal article
3467
10.15553/c2018v731a13
df71488b-e5e8-4563-9d8e-d3d90c442349
2235-3658
5684500
Capurodendron sahafariense
L. Gaut. & Naciri
,
spec. nova
(
Fig. 4
,
5
).
Holotypus
:
MADAGASCAR
. Prov.
Antsiranana
:
Reg.
DIANA
,
Sadjoavato
,
forêt de Sahafary
,
12°36’26”S
49°26’43”E
,
280 m
,
8.I.2007
, fl. & fr.,
Ratovoson
et al. 1217
(
G
[
G00418681
]!
;
iso-
:
CNARP
,
MO
[
MO-2108542
],
P
[
P04568840
]!,
TAN
).
Capurodendron sahafariense L. Gaut. & Naciri
shares a 5-ridged fruit with
C. costatum Aubrév.
from which it markedly differs by its much smaller leaves (6-25 × 2-7 vs 50 ×
30 mm
). Its venation pattern is similar to
C. ludiifolium Aubrév.
which also has much larger leaves. Its leaves are similar in size to that of
C. androyense Aubrév.
from which it differs by its winged fruits and its venation pattern.
Shrub
2 m
to small tree 10 (-15) m tall, with white latex and creviced bark; ultimate twigs
1-1.5 mm
in diam., greyish glabrous.
Leaves
coriaceous, caducous, spirally arranged at the tip of short 1.5-6.0 mm lateral branches (brachyblasts) with scars of fallen leaves and protuberances resulting from swollen stem below leaf insertion; blade 0.6-2.5 ×
0.2-0.7 cm
, obovate to narrowly obovate, brownish and clearly discolorous when dry with upper side darker, glabrous except for a few minute (
0.2-0.3 mm
) golden trichomes at base; apex obtuse to rounded, to retuse; base narrowly cuneate, indistinctly passing to a short petiole (max.
1.5 mm
long,
0.8 mm
in diam.); venation inconspicuous when fresh, especially on upper side, raised on both sides on dry specimens, reticulate, secondaries 3-4 on each side, almost indistinct from tertiaries, ascending at an angle of c. 20° from primary nerve, looping near margin.
Flowers
grouped in clusters of 1-6 among the leaves or on leafless brachyblasts; flowering pedicels 1.5-3.5 ×
0.5 mm
, densely golden-villous.
Sepals
5, quincuncial, glabrous inside, densely golden-villous outside, circular to ovate, apex rounded to obtuse, 2.4-3.0 ×
2.4 mm
, the three inner ones slightly keeled.
Corolla
gamopetalous with 5 lobes, glabrous, tube
1.8 mm
long, lobes broadly lanceolate, 3.0 ×
1.2 mm
, contorted in bud, spreading at anthesis, cream-coloured when fresh.
Stamens
5, filaments attached to the top of the corolla tube, the free part
0.9 mm
long. Anthers pair medifixed, extrorse, 1.0 ×
0.7 mm
, villous, connective broad, prolonged above anthers in a triangular glabrous apex
0.9 mm
long,
0.45 mm
at base.
Staminodes
5, alternate with respect to petals and stamens, 2.5 × 1.0 mm, densely villous with golden trichomes, carnose, connivent and concealing the ovary, spreading at apex.
Ovary
spherical but tapering towards style base,
1.2 mm
high and broad, slightly 5-lobed, villous with golden trichomes, with 5 ovules; style
5 mm
long, glabrous,
0.2 mm
in diam.
Fruiting pedicels
3.5 ×
1.1 mm
, glabrescent, with a persistent calyx.
Fruit
ovoid and slightly beaked, 18-20 ×
10-11 mm
, 5-ridged, mostly glabrous but with a pubescent base; apparently only one seed develops.
Fig. 3. -
Known distribution of
(A-B)
Capurodendron sahafariense
L. Gaut. & Naciri
(green),
(A, C)
C. schatzii
L. Gaut. & Naciri
(pink), and
(A, D)
C. nanophyllum
L. Gaut. & Naciri
(blue). Limits of protected areas in yellow. [Google Earth Images. Copyright 2018 DigitalGlobe. Reproduced per attribution guidelines]
Etymology
. – The epithet is derived from the name of the forest where the majority of the specimens, including the
type
, have been collected.
Fig. 4. -
Capurodendron sahafariense
L. Gaut. & Naciri.
A.
Longitudinal section of flower;
B.
Flower;
C.
Corolla opened seen from inside;
D.
Corolla opened seen from outside;
E.
Brachyblast with leaves and post-anthesis flower;
F.
Branch with flowers and fruit;
G.
Fruit;
H.
Transverse section of ovary. [Drawings: G. Loza]
Fig. 5. -
Field photograph of the type collection of
Capurodendron sahafariense
L. Gaut. & Naciri.
[Photo: F. Ratovoson]
Distribution, ecology and phenology
. – The species is only known from the dense dry deciduous forest on sands, in Sahafary and its SE vicinity (
Fig. 3
), in the northern part of the Western Phytogeographical Domain (
HUMBERT, 1955
). The flowering and fruiting collections were gathered between November and February.
Conservation status. –
The Sahafary forest has an area of c.
12 km
2
, and is well-known for being home of a range of narrow endemics, including another
Sapotaceae
species,
Manilkara sahafariensis
Aubrév.
It is very unfortunate that this forest has not been included in the recent extension of
Madagascar
protected area network, as it is under threat of being converted to agricultural land. Under these conditions and with an EOO of
41 km
2
and an AOO of
16 km
2
,
C.sahafariense
is assigned a preliminary IUCN conservation status of “Critically Endangered” [CR B1ab(i,ii,iii)].
Notes. –
Capurodendron sahafariense
has the remarkable feature of having a ridged fruit. In the genus, the only other species with ridged fruits is
C. costatum
,
which has also leaves on brachyblasts, but with blades 2.5 times longer and 5 times broader, and which is only found in the western part of the island, from Bemaraha to Ankarafantsika,
i.e.
more than
450 km
south-west from the Sahafary forest where the new species has been discovered. The two species might be related, but this still has to be confirmed by an undergoing molecular study. The venation pattern in
C. sahafariense
reminds
C. ludiifolium
,
which has unridged fruits and larger leaves.
Paratypi
. –
MADAGASCAR
. Prov.
Antsiranana
:
Reg.
DIANA
, forêt
d’Analafondro
, au pied SE du plateau de Sahafary (bassin inférieur du Rodo),
27.XII.1963
, fl.,
Service Forestier
23087
(
G
,
P
,
TEF
)
;
ibid. loco,
7.II.1966
, fl.,
Service Forestier
24517
(
G
,
P
,
TEF
)
;
forêt de Sahafary (bassin de la Saharenena)
,
7.II.1966
, fl.,
Service Forestier
24487
(
G
,
P
,
TEF
)
;
Ambolobozobe
,
Ambovomavo
, à
1 km
W du village d’Ambolobozobe,
12°31’13”S
49°31’21”E
,
24.XI.2007
, fl.,
Rakotonandrasana
1207
(
CNARP
,
G
,
MO
,
P
,
TAN
).