A revision of Xylopia L. (Annonaceae): the species of Tropical Africa
Author
Johnson, David M.
Department of Botany-Microbiology, Ohio Wesleyan University, Delaware, OH, 43015, USA
Author
Murray, Nancy A.
Department of Botany-Microbiology, Ohio Wesleyan University, Delaware, OH, 43015, USA
namurray@owu.edu
text
PhytoKeys
2018
2018-04-24
97
1
252
http://dx.doi.org/10.3897/phytokeys.97.20975
journal article
http://dx.doi.org/10.3897/phytokeys.97.20975
1314-2003-97-1
BD026E15CD67FF99E01FF605FFF6FFEF
1239255
39.
Xylopia piratae D. M. Johnson & N. A. Murray
sp. nov.
Figs 3F
, 33H-J
Diagnosis
.
Species resembling
Xylopia thomsonii
in the twig indument consisting of both short and long erect hairs, the one-flowered inflorescence with multiple overlapping bracts on the short pedicel, and the linear petals, but differing in the more
strongly
lianescent habit with ultimate branches departing at right angles to the twig that bears them, the leaves only 4.1-11.3 cm long, the outer petals reaching 73 mm in length, carpels only 4-9 per flower, and monocarps only 0.5-0.7 cm in width with a more pronounced beak.
Type
.
IVORY COAST
.
Grand Bassam Department
,
foret
de
l'Abouabou
, between
Abidjan
and
Grand Bassam
,
2 m
,
6 Jan 1959
,
A. J. M. Leeuwenberg
2365
(
holotype
: WAG! [0005952]; isotypes: K! P!)
.
Description.
Liana
extending to 20 m, or occasionally a shrub, the ultimate branches often departing at right angles to the twig that bears them and slightly thickened at the base.
Twigs
brown, pubescent, the hairs 0.5-1.2 mm long, soon dark brown to gray-brown, glabrate, sometimes with bark exfoliating; no nodes with two axillary branches seen.
Leaf
with larger blades 4.1-11.3 cm long, 1.9-3.9 cm wide, chartaceous, concolorous to discolorous, elliptic, oblong, oblong-oblanceolate, or lanceolate, apex acuminate, the acumen 2-11 mm long, base broadly cuneate to rounded, pubescent on the midrib but otherwise glabrous adaxially, finely appressed-pubescent to glabrate abaxially; midrib plane adaxially, raised abaxially, secondary veins weakly brochidodromous, 8-15 per side, diverging at 65-70° from the midrib, these and higher-order veins indistinct to raised adaxially, slightly raised to raised abaxially; petiole 1.2-3.5 mm long, shallowly canaliculate, sparsely pubescent to glabrate.
Inflorescences
axillary, 1-flowered, pubescent; pedicels 3.2-4.5 mm long, 0.8-1.2 mm thick; bracts 4-5, imbricate over length of pedicel, persistent, 1.7-3 mm long, ovate to circular, apex acute to rounded; buds linear-lanceolate, somewhat falciform, apex acute.
Sepals
slightly spreading at anthesis, 1/4-1/3-connate, 2.4-3.1 mm long, 2.2-3.0 mm wide, chartaceous, ovate to broadly triangular, apex acute to acuminate, sericeous abaxially.
Petals
cream-colored to white
in vivo
; outer petals spreading but curved inward toward the apices at anthesis, 24.3-73 mm long, 2.6-4 mm wide at base, 1.0-1.5 mm wide at midpoint, subcoriaceous, linear, apex acute, puberulent but becoming glabrous and warty in the proximal 1/3-1/2 adaxially, puberulent abaxially; inner petals spreading but curved inward toward the apices at anthesis, 25.8-48 mm long, 2.1-3.4 mm wide at base, 0.6-1.0 mm wide at midpoint, subcoriaceous, linear, apex acute, base with undifferentiated margin, puberulent, glabrous in the proximal 1/3 adaxially, sparsely puberulent abaxially.
Stamens
ca. 100; fertile stamens 0.9-1.5 mm long, narrowly oblong, apex of connective ca. 0.2 mm long, shieldlike to dome-shaped, overhanging the anther thecae, glabrous, anthers ca. 12-13-locellate, filament 0.2-0.4 mm long; outer staminodes 1.3-1.6 mm long, clavate, apex obtuse to obliquely truncate; inner staminodes 0.8-1 mm long, oblong to clavate, apex truncate; staminal cone 1.7-2.0 mm in diameter, 0.6-1.1 mm high, concealing lower half of the ovaries, rim laciniate.
Carpels
4-9; ovaries 1.0-1.4 mm long, narrowly oblong, densely pubescent, stigmas connivent, 3.4-4 mm long, filiform, apex acute, with short tuft of hairs at apex but otherwise glabrous.
Torus
flat, ca. 2.4 mm in diameter.
Fruit
of up to 6 sparsely pubescent to glabrate monocarps borne on a pedicel 6.5-6.8 mm long, 2.2-2.7 mm thick, sparsely pubescent to glabrate; torus ca. 5.5 mm in diameter, 3.5 mm high, depressed-globose.
Monocarps
with a green, sometimes purple-tinged, exterior and red endocarp
in vivo
,
3.1
-6.6 cm long, 0.5-0.7 cm wide, ca. 0.7 cm thick, narrowly oblong and slightly falciform, torulose, apex with a curved beak 1.5-3 mm long or occasionally rounded, base contracted into a stipe 5-12 mm long, 1.2-3.2 mm thick, verrucose; pericarp ca. 0.4 mm thick.
Seeds
up to 9 per monocarp, in a single row, lying oblique to long axis, 9-10.9 mm long, 5.5-7.5 mm wide, 5.6-6.1 mm thick, ellipsoid, broadly elliptic in cross-section, obliquely truncate at micropylar end, rounded at chalazal end, light brown, smooth, dull, raphe/antiraphe not evident, micropylar scar 1.7-5 mm long, 1.4-3.5 mm wide, elliptic, oblong, or circular with the endostome protruding; sarcotesta pale gray to green
in vivo
; aril absent.
Phenology.
Specimens with flowers have been collected from October to February and in April, May, July, and August; specimens with fruits have been collected from November to January and in July and August.
Distribution
(Fig.
34
). Occurs from southern Ivory Coast east to southwestern Ghana, growing in coastal thickets and savanna, sometimes in secondary forest, at elevations from sea level up to 50 m.
Additional specimens examined.
IVORY COAST
.
Bords de la lagune
Ebrie
, 1932 (fr),
Aubreville
1537
(K); Km 25 Sassandra-Gagnoa, ca.
5.5N
,
6.5W
,
30 Oct 1968
(fl),
Breteler 5856
(K, MO, WAG); near
Grand Bassam
, NW
along Rd. to Aboisso, ca.
5°13'N
,
3°43'W
,
12 Nov 1968
(fl),
Breteler 5983
(B, K, M, MO, NY, U, WAG); near
Mafere
,
5°23'N
,
3°05'W
,
23 Apr 1974
(fl),
Breteler 7445
(MO);
Banco Forest Reserve
, near
Abidjan
,
50 m
,
24 Jan 1970
(fl),
de Koning
84
(WAG-2 sheets);
Banco Forest Reserve
,
22 Dec 1972
(fl),
de Koning
983
(WAG);
25 Apr 1973
(fl),
de Koning
1555
(WAG);
10 Dec 1974
(fl),
de Koning
4999
(WAG-2 sheets),
10 Dec 1974
(bud, fr),
de Koning
5000
(WAG);
Abidjan
,
Banco Forest Reserve
,
5 May 1976
(fl),
de Koning
6856
(WAG-2 sheets);
foret
de
l'Abouabou
, between
Abidjan
and
Grand Bassam
,
5°14'N
,
3°33'W
,
2 m
,
1 Aug 1970
(fl),
Leeuwenberg
8022
(B, K, MO, P, U); about
10 km
W of Jacqueville
, island
Aladian
,
5°11'N
,
4°32'W
, 0 m,
3 Aug 1970
(yg fr),
Leeuwenberg
8089
(K); E of
Tabou
,
Yokobo
,
4°26'N
,
7°22'W
,
9 Nov 1981
(fl),
Leeuwenberg
12304
(WAG);
Ile Bonbay
,
pres
Adiopodoume
,
29 Aug 1955
(fr),
Nozeran
s. n.
(BR, P); savane
d'Abouabou
,
between Abidjan and Grand Bassam
,
28 Nov 1963
(fl),
Oldeman
682
(K, P);
Arboretum
,
foret
du Banco
(cultiv.),
6 Dec 1956
(fl),
de Wilde
982
(WAG); I.
R. H.
O. (Cocos cultures) ca.
20 km
W of Grand Bassam
, near the beach on sandy soil between
Port Bouet
and
G. Bassam
,
1 Jul 1963
(fl),
de Wilde
354
(K, P),
1 Jul 1963
(fr),
de Wilde
356
(K, P); ca.
5 km
SE of O.
R. S.
T. O.
M.,
Ile Boulay
, beyond
Lagune
Ebrie
,
22 Jul 1963
(fr),
de Wilde
497
(BR, K);
foret
d'Andouin
,
24 Aug 1955
(fr),
de Wit
7999
(WAG)
.
GHANA
.
Princes
[Town],
9 Jan 1939
(fl, fr),
Akpabla 767
(K-2 sheets);
Atwabo, W
. Province,
Feb 1934
(fl),
Irvine 2299
(K); Western, Bia Reserves, along borderline
between Bia National Parc and Bia Production Reserve
, near Camp 15,
6°32'42"N
,
3°02'00"W
,
13 Nov 1993
(fr),
Jongkind
et al. 1301
(MO)
.
Xylopia piratae
bears pure white flowers with slender petals that, at
70 mm
, are among the longest known in the genus.
The
climbing habit of the plants is more strongly developed than in any other species of
Xylopia
: label descriptions invariably refer to the climbing or scrambling growth form, and on the label of
de Koning
983
the
plant
is described as reaching a length of
20 m
.
Plants
identified as
X. acutiflora
by
Hall and Swaine (1981)
from forest plots in southwestern
Ghana
and described as "a woody climber with leafy shoots of limited growth inserted approximately at right angles to the main stem, as in
Uvaria ovata
," probably represent this species rather than
X. acutiflora
.
In
addition, there is a tendency in
X. piratae
for the shoots inserted at right angles to have a slight thickening where they join the supporting branch;
Xylopia dinklagei
shows a similar tendency.
The
sweet scent of the flowers has been noted by many collectors;
Leeuwenberg
12304
added that the flowers were fragrant at 1700 h.
This
species is named in memory of
Celine Pirat
, who photographed the plants (Fig.
3F
) on
Ile Assoko
,
Ivory Coast
, on
10 May 2014
.
Xylopia piratae
most closely resembles
X. thomsonii
from central Africa. Both species have a tendency for the branches to become lianescent, although this is more extreme in
X. piratae
. Both have a mixture of both long and short erect hairs persistent on the twigs. The petals of
X. thomsonii
, while they do not reach the length of those of
X. piratae
, are long for this species subgroup but broader. The liana habit and extremely long petals combine to distinguish
X. piratae
from both
X. acutiflora
and
X. dinklagei
, the other two species of the
X. acutiflora
subgroup found in West Africa.
Three specimens from southern
Togo
may represent
Xylopia piratae
:
Schaefer
7577
(GH, MO, WAG-2 sheets),
de Wit & Morton A2895
(WAG), and
Ern 2710
(B-2 sheets). The specimens are incomplete, and no habitat information is given for these specimens.
Xylopia piratae
is one of three
Xylopia
species endemic to the
Guinea
Coast region of West Africa, all of them with relatively narrow distributions and all belonging to the
Xylopia acutiflora
subgroup. For
Xylopia piratae
, we calculated an EOO of
31,476 km
2 and an AOO of
64 km
2. Its narrow coastal savanna distribution may make it vulnerable to habitat loss. It may be somewhat tolerant of disturbance, however, as several collections are from secondary forest habitat and the collection
Leeuwenberg 8022
, bearing flowers, was taken from a shoot regenerating from a stump in
Alchornea cordifolia
thicket.