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
29.
Xylopia longirostra
D.M.Johnson & N.A.Murray
,
sp. nov.
(
Fig. 25A-E
)
Species resembling
Xylopia ambanjensis
and
X. lastelliana
in the lanceolate leaves under
9 cm
long with acuminate apices, but differing from both in the leaf acumen forming 1/4-1/5 rather than 1/6-1/8 of the leaf length. It additionally differs from
X. ambanjensis
in the subcoriaceous rather than chartaceous leaves, the absence of persistent hairs along the leaf margins, and the mature monocarps larger,
3.8-5 cm
long, and more prominently lenticellate. From
X. lastelliana
it differs in the sparsely appressed-pubescent rather than densely sericeous abaxial leaf surfaces.
TYPE. —
Madagascar
.
Prov. Toamasina
,
Vohibola
,
forest N to NNW of village of Andranokoditra
,
N of Lac Ampitabe
,
18°33’34”S
,
49°15’17”E
,
5 m
,
12.II.2003
(fr.),
Lowry et al. 6064
(holo-,
MO
!;
iso-,
OWU
!, P[P01987028]!).
PARATYPES
. —
Madagascar
. Prov.
Toamasina
,
Analanjirofo Region
,
Vavatenina
,
Sahatavy
,
Sahalangina
, forêt
d’Anjirobe
,
17°28’02”S
,
48°54’23”E
,
550 m
,
26.X.2000
(buds),
Andrianjafy
et al. 120
(
MO
)
;
à
Ambila-Lemaitso
,
14.XII.1967
(fr.),
Capuron
28035 SF
(K, P[P01987026]
;
Foulpointe
,
22.I.1973
(st.),
Debray
1974
(P[P02034676, P02034677])
;
Fivondronana
:
Brickaville
,
Firaisana
:
Ambinaninony
,
Fokontany
:
Andranokoditra
, 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. 854
(K,
MO
, P[P01987029])
;
Analanjirofo Region
,
Fivondronana Vavatenina
,
Commune Ambodimangavalo
, limite
du Parc
national
de Zahamena
,
17°33’41”S
,
48°54’14”E
,
850 m
,
2.V.2003
(immature fr.),
Rakotonandrasana
et al. 682
(
OWU
, P[P01954127])
;
Fivondronana
:
Brickaville
,
Firaisana
:
Ambinaninony
,
Fokontany
:
Andranonkoditra
, forêt littorale
de Vohibola
,
18°33’55”S
,
49°15’22”E
,
3 m
,
24.X.2002
(fr.),
Razakamalala
266
(K,
MO
,
NY
)
.
DISTRIBUTION, ECOLOGY AND CONSERVATION STATUS. — Five of the seven collections of
X. longirostra
,
sp. nov.
, were made in the Vohibola coastal littoral forest area of east-central
Madagascar
, where the species occurs with
X. retusa
,
sp. nov.
, another near-endemic to the area and two more widespread
Xylopia
species,
X. buxifolia
and
X. humblotiana
. Two incomplete specimens of
X. longirostra
,
sp. nov.
, have also been collected from humid forest on low summits inland at elevations of 550 and 850 meters (
Fig. 29
). A specimen with flower buds was collected in October, and the specimens with fruits were collected in February, May (immature), October, and December. The EOO of
5003 km
2
and AOO of
24 km
2
lead to a preliminary conservation assessment of Endangered (
Table 2
).
LOCAL NAME. — Ankahatra madinika lava ravina (
Rakotonandrasana 682
), hazoambo (
Andrianjafy et al. 120
).
DESCRIPTION
Tree
up to
12 m
tall; d.b.h. up to
20 cm
.
Twigs
glabrous or sparsely pubescent, the hairs
0.1-0.4 mm
long, soon glabrate; nodes with one or often two axillary branches.
Leaves
with larger blades 4.9-7.0 cm long,
1.3-1.7 cm
wide, subcoriaceous, slightly discolorous, brown-olive adaxially, light brown abaxially, lanceolate to oblong-lanceolate, apex acuminate, the acumen
9-16 mm
long, base cuneate, short-decurrent on petiole, margin slightly recurved, glabrous adaxially, sparsely appressed-pubescent abaxially; midrib reddened toward base adaxially, secondary veins weakly brochidodromous, 11-13 per side, diverging at 50-70° from midrib, these and higher-order veins slightly raised on both surfaces; petiole
3-5.5 mm
long, canaliculate, slightly wrinkled, glabrate or with a few hairs.
Inflorescences
axillary from the axils of newly expanding shoots, 1-flowered, not pedunculate, sparsely pubescent; pedicels [probably not fully elongated]
1.8-2.5 mm
long,
c.
0.7 mm
thick; bracts 2, both attached near the pedicel midpoint, persistent [but flowers immature],
0.9-1.2 mm
long, broadly ovate to semicircular; buds lanceolate, apex acute.
Sepals
with position at anthesis unknown, ¹⁄5-1/3-connate,
c.
1.3 mm
long,
c.
1.6 mm
wide, coriaceous, ovate to broadly triangular, apex acute, margins ciliate and with a few sparse hairs abaxially.
Petals, stamens, and carpels
unknown.
Fruit
of up to 4 monocarps borne on a pedicel
4-7 mm
long,
3.5-4.5 mm
thick, glabrate; torus
5.5-10 mm
in diameter,
6-7 mm
high, depressed-globose; monocarps with orange yellow to red exterior
in vivo
, 3.8-5.0 cm long,
2.3-2.4 cm
wide,
2.3-2.6 cm
thick, ellipsoid to ovoid, not torulose, apex rounded, base sessile or occasionally contracted into a stipe
3.5-4 mm
long,
5.5-9 mm
thick, verrucose, longitudinally wrinkled, conspicuously marked with raised lenticels, dull, glabrate; pericarp
c.
2.1 mm
thick.
Seeds
c.
10 per monocarp, in two rows, perpendicular to long axis,
18.7-19.6 mm
long,
10.7-11.4 mm
wide,
8.5-9.2 mm
thick, oblong-ellipsoid, broadly wedge-shaped in cross-section, chestnut brown, smooth, slightly shiny, perichalazal ring not evident; presennce of sarcotesta undeterminable; aril absent.
NOTES
Xylopia longirostra
,
sp. nov.
, has relatively small narrow leaves similar to those of
X. ambanjensis
, but the leaves are subco- riaceous and shiny adaxially and, as indicated by the specific epithet, have an acumen forming a greater proportion of the total blade length, about ¼-¹⁄5 rather than ¹⁄6-1/8. The leaves are also less hairy than those of
X. ambanjensis
, lacking the persistent hairs along the midrib and leaf margins. The monocarps of
X. longirostra
,
sp. nov.
, are prominently lenticellate and much larger than those of
X. ambanjensis
, with seeds over
18 mm
long. The lenticels are often prominent on the twigs as well, giving them a bumpy appearance. Another character that
X. longirostra
,
sp. nov.
, and
X. ambanjensis
have in common is that the leaf acumen is wrapped around itself early in development and sometimes remains that way in mature leaves (
Fig. 25B
).
Xylopia lastelliana
resembles
X. longirostra
,
sp. nov.
, in its leaf shape and fruit morphology, and occurs in similar localities in a comparable range of elevations.
Xylopia longirostra
,
sp. nov.
, is readily distinguished from
X. lastelliana
, however, by the absence of sericeous leaf indument on the leaves as well as by the longer and more abrupt leaf acumen.
The specimens
Andrianjafy et al. 120
and
Rakotonandrasana 682
were collected some distance from the coast and slightly north of the forests where the other specimens were collected, but the leaves are identical in shape and texture. One of these specimens has only flower buds, while the other has only immature fruits, which limits additional comparisons.