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
17.
Xylopia holtzii Engler, Bot. Jahrb. Syst. 34: 159. 1904.
Figs 27G-K
, 28A
Type
.
TANZANIA
.
Dar-es-Salaam Region
,
Dar-es-Salam
,
Puguberge
,
Dichter Busch
,
29 Feb 1903
,
W. Holtz
s. n.
(
lectotype
, here designated: B! [100153143])
.
Tree
up to
20 m
tall, d.b.h. up to
30 cm
, clear bole to
8 m
on
12 m
tree, trunk fluted or with small narrow buttresses at base; bark light gray to gray-brown, sometimes blotched with white, smooth or transversely ringed by fine lenticels.
Twigs
light brown, orange-brown, gray-brown, brownish gray, or blackish brown, initially pubescent, the hairs
0.1-0.8 mm
long, becoming glabrate; nodes occasionally with two axillary branches.
Leaf
with larger blades
4.8-11.4 cm
long,
1.7-4.4 cm
wide, chartaceous to subcoriaceous, concolorous to slightly discolorous, lanceolate to narrowly oblong, elliptic, or oblanceolate, apex obtuse, often attenuate, rarely emarginate, base broadly cuneate to rounded, glabrous to sparsely pubescent adaxially, sparsely appressed-pubescent abaxially; midrib slightly raised to plane adaxially, raised abaxially, secondary veins weakly brochidodromous, 8-17 per side, diverging at 40-70° from the midrib, slightly raised on both surfaces, higher-order veins indistinct adaxially, indistinct to slightly raised abaxially; petiole
3-12 mm
long, shallowly canaliculate to flattened, pubescent or rarely glabrous.
Inflorescences
axillary, 1-6-flowered, pubescent; at least some inflorescences with peduncles, 1-2 peduncles per axil,
2-4.5 mm
long; pedicels 2-4 per peduncle, or arising directly from axil, 2.0-
7.5 mm
long,
0.7-0.8 mm
thick; bracts 2-3, evenly spaced along length of pedicel, caducous or rarely persistent,
0.9-1.3 mm
long, ovate to semicircular, apex acute to rounded; buds linear, slightly falciform, apex acute.
Sepals
erect to slightly spreading at anthesis, 2/5-1/2-connate,
1.6-2.4 mm
long,
1.9-2.8 mm
wide, coriaceous, orbicular, apex acute to short-acuminate, appressed-pubescent abaxially.
Petals
yellow-green, yellow, or cream-colored with pinkish purple at the base adaxially
in vivo
; outer petals curved outward but with the apices weakly incurved at anthesis,
10.5-25 mm
long,
2.1-3.7 mm
wide at base, (0.7-)
0.9-1.9 mm
wide at midpoint, coriaceous, linear, apex acute to obtuse, weakly keeled on abaxial surface, gray-puberulent adaxially, golden appressed-pubescent abaxially; inner petals curved outward but with the apices strongly incurved at anthesis,
7.7-21.4 mm
long,
1.6-2.7 mm
wide at base,
0.5-1.2 mm
wide at midpoint, coriaceous, linear-subulate, apex acute, base with undifferentiated margin, ridged on both surfaces, densely puberulent on both surfaces.
Stamens
60-70; fertile stamens 1.0-
1.5 mm
long, narrowly oblong, apex of connective red to reddish purple
in vivo
,
0.1-0.3 mm
long, shieldlike, overhanging anther thecae, glabrous, anthers 10-13-locellate, filament
0.3-0.5 mm
long; outer staminodes
0.9-1.4 mm
long, quadrate to broadly clavate, apex truncate; inner staminodes 1.0-
1.2 mm
long, clavate, apex truncate; staminal cone
0.7-1.9 mm
in diameter,
0.7-1.1 mm
high, concealing only the bases of the ovaries, rim laciniate.
Carpels
5-12; ovaries
0.9-1.1 mm
long, narrowly oblong, pubescent; stigmas loosely connivent,
0.9-1.8 mm
long, linear, apices pubescent.
Torus
flat,
1.6-2.4 mm
in diameter.
Fruit
of up to 8 pubescent monocarps borne on a pedicel
4.5-8 mm
long, 1.6-3.0 mm thick, pubescent; torus 3.0-
6.7 mm
in diameter,
2.6-5.4 mm
high, irregularly globose.
Monocarps
with green exterior and white (immature?) endocarp
in vivo
, up to 8 per fruit, 2.3-4.0 cm long,
0.8-1.3 cm
wide,
0.7-0.8 cm
thick, oblong, irregularly torulose, apex obtuse to rounded, often with a wide beak
1.5-2.2 mm
long, base contracted into a stipe
6-10 mm
long,
3-3.5 mm
thick, finely verrucose, pubescence most persistent on stipe; pericarp 0.4-1.0 mm thick.
Seeds
1-3 per monocarp, in a single row, lying oblique to long axis,
11.8-12.3 mm
long, 5.9-7.0 mm wide, 4.9-6.0 mm thick, flattened-ellipsoid, broadly elliptic in cross-section, obliquely truncate at micropylar end, rounded at chalazal end, brown, smooth, shiny, raphe/antiraphe not evident, micropylar scar
1.4-1.9 mm
long, 0.9-1.0 mm wide, oblong, elliptic, or ovate-elliptic; sarcotesta orange
in vivo
; aril absent.
Figure 27.
Xylopia longipetala
,
X. holtzii
,
X. katangensis
, and
X. shirensis
.
A-F
X. longipetala
A
Fruit
B
Seed, side view
C
Seed, view of micropylar end
D
Base of inner petal, adaxial view
E
Habit
F
Gynoecium surrounded by staminal cone with a few attached stamens
G-K
X. holtzii
G
Habit
H, I
Detached monocarps
J
Gynoecium surrounded by staminal cone with a few attached stamens
K
Base of inner petal, inner (adaxial) surface
L
X. katangensis
, habit
M-P
X. shirensis
M
Fruit
N
Habit
O
Seed, view of micropylar end
P
Seed, side view.
A-C
from
Jongkind & Nieuwenhuis 3031
(WAG)
D, F
from
McPherson 17911
(MO)
E
from
Halle
& Le Thomas 190
(
P
), and following photograph of fresh flowers of same collection in
Le Thomas (1969)
G, J, K
from
Johnson et al. 1938
(OWU)
H, I
from
Templer H167/53
(K),
L
from
Letouzey 4498
(MO)
M
from
Richards 13266
(K)
N
from
Richards 14438
(K)
O, P
from
Bredo 6276
(BR).
Phenology.
Specimens with flowers have been collected in February, March, from May to July, and from October to December, and with fruits from January to March, in May and August, and from October to December.
Distribution
(Fig.
26
). Occurs near the Indian Ocean coast from southern Kenya to central Tanzania, extending inland in Tanzania to the scarp of the Udzungwa Mountains and the Selous region, growing in dry evergreen or semi-deciduous forest, less commonly in miombo (
Brachystegia
) woodland, at elevations of 0-800 (-1670) m.
Local names.
Lulema mbala (
Rodgers 388
); mlawilila (Kidoe,
Abeid 550
), muporota (Kihehe,
Haerdi 214/0
), mporoto (Kimbunga,
Haerdi 214/0
), mporota (Kisagara,
Haerdi 214/0
). An ethnobotanical study of the Digo people on the coast between Tanga and Mombasa reported mnyinyi [shining leaves], mchiza tasaka, and mwahula tsaka [forest breaker, i.e. emergent through the canopy] (
Pakia 2005
) as additional local names in that area.
Additional specimens examined.
KENYA
.
Kwale
:
Jardini
,
Jun 1962
(fl),
Birch
62/188
(K);
Jilori
,
Black M.
37
(K)
;
Kwale District
,
Mwasangombe Forest
15 km
SW of
Kwale
,
230 m
,
27 Aug 1953
(fr),
Drummond
&
Hemsley
4015
(B, EA, FI-T, K);
Jardini Hotel
, forest ca.
30 km
S of
Mombasa
,
22-23 Jun 1970
(fl),
Faden
70/201
(EA, K, MO);
Diani Forest
,
1 km
N to
1.5 km
S of the turnoff for the new road to
Jadini Hotel
,
4°19'S
,
11-13 Jul 1972
(fl),
Gillett
&
Kibuwa
19846
(B, BR, EA, K, MO, NHT, P, WAG);
Gillett
&
Kibuwa
19847
(K);
Mkongani North FR
,
4°17'S
,
39°19'E
,
280 m
,
13 Jul 1987
(bud),
Luke
&
Robertson
508
(MO);
Diani Forest
,
4°20'S
,
39°34'E
,
5 m
,
16 Jun 1994
(fl),
Robertson 6957
(K, MO); Mrima Hill,
4°29'S
,
39°16'E
,
170 m
,
4 Feb 1989
(st),
Robertson
et al. MDE 50
(K);
Gogoni
,
30 mi
S of
Mombasa
,
7 Oct 1953
(fl, fr),
Templer H
167/53
(K-2 sheets, MO)
.-
Lamu
:
Witu District
,
Mambasasa
,
7 Nov 1957
(old fl),
Greenway
9471
(FI-T, K, PRE)
.
TANZANIA
.
Iringa
:
Kilolo District
,
Kisegese Village
, at base of hill,
08°01'58"S
,
036°22'46"E
,
360 m
,
13 Mar 2006
(fl, fr),
Festo
et al. 2213
(MO)
.-
Lindi
:
Selous Game Reserve
, T8, ca.
15 km
SSW of Kingupira
,
8°35'S
,
38°31'E
, ca.
150 m
,
15 Nov 1975
(fl),
Vollesen
2992
(K, WAG)
.-
Morogoro
:
Hundupila
/
Kiberege
,
Ifakara
,
6 Mar 1959
(fl),
Haerdi
214/0
(K, WAG); along trail to
Mwanihana Peak
,
SW of Udzungwa Mountains National Park
headquarters, 19/
20 Feb 1996
(fl, fr),
Johnson
&
Murray
1889
(OWU spirit collection)
;
Ulanga District
,
Iragua village
,
100 m
SE of main road from
Iragua
to
Itete
,
8°33'54"S
,
36°29'52"E
,
360 m
,
21 Jan 1999
(fr),
Kayombo
1589
(MO);
Sanje Logging Camp
,
1670 m
,
30 Dec 1980
(fr),
Rodgers
388
(DSM)
.-
Pwani
:
Bagamoyo District
,
Zaraninge Forest Reserve
, near WWF office, near forest
guards'
camp,
6°17'S
,
38°34'E
,
150 m
,
8 Jun 1999
(fl),
Abeid
550
(MO);
Pugu-Berge
, s. d.,
Holtz
3202
(B, PH)
;
Coast Region
,
Kisarawe
District,
Pugu Forest Reserve
, bus roundabout area ca.
4 km
E of Kisarawe
,
06°53'30"S
,
39°06'00"E
,
200 m
,
26 May 1996
(fl),
Johnson
&
Murray
1938
(OWU)
;
Rufiji District
, forest near WWF
Office
,
08°18'57"S
,
38°57'39"E
,
250 m
,
6 Dec 1998
(fl),
Kibure 320
(MO); T6,
Kisarawe
,
Pugu Forest Reserve
,
June 1954
(fl),
Semsei 1718
(EA, K-2 sheets);
Selous Game Reserve
, Beho Beho,
07°40'S
,
37°55'E
,
250 m
,
6 Jun 1977
(fl),
Vollesen
4619
(DSM, WAG)
.-
Tanga
:
Kihuhwi R.
,
E Usambaras
,
900 ft
,
Greenway
4959
(K).-
Region
undetermined: T6,
Nahomba
,
Selous Game Reserve
,
7 Nov 1970
(fr),
Ludanga
1166
(K);
Kijawe
,
Selous Game Preserve
,
2 Feb 1971
(fl),
Ludanga
1193
(EA, K); T6,
Selous Game Reserve
,
24 May 1978
(fr),
Mhoro
2917
(MO); T8,
Balani
water hole,
Selous Game Reserve
,
4 Oct 1970
(fl),
Rodgers
1148
(K)
.
Xylopia holtzii
is another member of the
X. odoratissima
subgroup of eastern and southern Africa, set apart from other species of the subgroup by the combination of branched inflorescences, purple coloration at the bases of the petals, and pubescent stipitate monocarps that are only weakly verrucose. The number of branched inflorescences on herbarium specimens varies-some sheets of
Vollesen 2992
from the Selous region, for example, have no branched inflorescences, but correspond to the species in leaf and floral morphology. In
Tanzania
,
X. holtzii
is not known to overlap in distribution with either
X. shirensis
or
X. gracilipes
. The former is a species of the interior miombo woodlands to the west of the Eastern Arc Mountains, while the latter is only known from the miombo woodlands of the extreme southern
Tanzania
, where it reaches the northern limit of its distribution.
Given the variable nature of the habitats in which this species occurs, it is not surprising that tree associates vary correspondingly from location to location. The most frequently mentioned associates are
Milicia excelsa
and species of
Erythrophleum
and
Diospyros
.
Marshall (2007)
reported
X. holtzii
(as
X. parviflora
) to be one of the ten most common canopy tree species in disturbed semi-deciduous forest plots in the Udzungwa Mountains, comprising 7.5% of the 3346 canopy tree individuals sampled.
The
type specimen of
Xylopia holtzii
cited above, which was marked as the
Typus
at B, bears information slightly different from that which is included in
Engler's
protologue:
"Sansibarkuestgebiet
: Pugu-Berge in
Buschgehoelzen
auf rotem Lehm (Holtz n. 897 - Fruchtend im
Feb 1903
)." The specimen is not discordant with the protologue, but in the case that there was a specimen with this number that has now been lost, the extant specimen is designated as a
lectotype
rather than assumed to be the
holotype
.