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
13.
Xylopia collina Diels, Notizbl. Bot. Gart. Berlin-Dahlem 13: 271-272. 1936.
Figs 3I
, 4E
, 21A, C, F, H, I, J
Xylopia latipetala
Verdcourt, Kew Bull. 25(1): 12. 1971. Type. TANZANIA. Lindi District: Rondo Plateau, Nahoro in
Albizia
,
Chlorophora
woodland, on old termite-hill, 11 Dec 1955 (fl),
Milne-Redhead & Taylor 7617
(holotype: K-2 sheets!).
Type
.
TANZANIA
.
Lindi Region
,
40 km
westlich von
Lindi
,
Lutambasee
[
"Lumbatasee"
],
14 Oct 1934
,
H.-J. E. Schlieben
5470
(
lectotype
, here designated: B! [10 0153136]; isotypes: B! [100153137, 100153138, 100153139], BM! [000511056], BR! [0000008824783], G! [00190716], HBG [502482, 502483, 502484], K! LISC! [000402], M! [0107918], MA! [385126], MO! [1703951], P! [00363256], PRE! [0397107-0], S! [07-13459],
US
! [2214646]).
Description.
Shrub or small tree
up to 4 m tall, d.b.h. up to 4 cm, twigs often somewhat flexuous on new growth.
Twigs
brown to reddish brown, densely erect-pubescent, the hairs 1-2 mm long, becoming gray-brown, glabrate or with the hairs somewhat persistent, bark developing minute exfoliations on the leafless growth; nodes occasionally with two axillary branches.
Leaf
with larger blades 4-8.4 cm long, 2.1-4.4 cm wide, chartaceous, concolorous or slightly discolorous, elliptic to ovate, occasionally lanceolate or obovate, apex acute to rounded, base subcordate or rounded, uniformly pubescent with hairs persistent on both surfaces and on the margin, slightly denser on the midrib; midrib plane to slightly raised adaxially, slightly raised abaxially, secondary veins indistinctly brochidodromous, 6-13 per side, diverging at 35-70° from the midrib, these and higher-order veins slightly raised on both surfaces; petiole 2-4 mm long, shallowly canaliculate, pubescent.
Inflorescences
axillary, 1-flowered, pubescent; pedicels not pedunculate, 1-3 mm long, 0.6-1.5 mm thick; bracts 2, evenly spaced along pedicel, caducous or rarely persistent, 1-2.7 mm long, semicircular or crescent-shaped, apex obtuse; buds lanceolate to ovoid, apex acute.
Sepals
erect to slightly spreading at anthesis, 1/5-1/2-connate, 2.5-4.1 mm long, 2.5-3 (-4.8) mm wide, coriaceous, ovate, apex acute, pubescent abaxially.
Petals
dull red to grayish pink
in vivo
; outer petals erect at anthesis, 9-20.4 mm long, 2.5-8 mm wide, 1.4-3.9 mm wide at midpoint, coriaceous to fleshy, linear-lanceolate to lanceolate, apex acute, densely puberulent on both surfaces except for a glabrous patch at base adaxially; inner petals geniculate at anthesis, with the apices bent sharply outward between the outer petals, 6-15.4 mm long, 2-5.2 mm wide, wide, 0.4-2.3 mm wide at midpoint, coriaceous to fleshy, lanceolate-acuminate, apex acute, base with undifferentiated margin, transversely thickened at the widest point adaxially, bearing a band of corrugated tissue just above the claw, puberulent except for glabrous base adaxially, puberulent on narrow apical portion and medial region of base but otherwise glabrous abaxially.
Stamens
120-200; fertile stamens 0.8-1.4 mm long, narrowly oblong to clavate, apex of connective 0.1-0.3 mm long, shieldlike or slightly hemispheric, overhanging the anther thecae, papillate, anthers 10-17-locellate, filament 0.3-0.4 mm long; outer staminodes 1.0-1.3 mm long, clavate, apex truncate, sometimes oblique; inner staminodes 0.8-0.9 mm long, clavate to oblong, apex rounded to truncate; staminal cone 1.7-2.8 mm in diameter, 1.0-1.7 mm high, concealing only the bases of the ovaries, rim laciniate.
Carpels
3-7; ovaries ca. 1 mm long, oblong, sericeous, stigmas connivent, ca. 1.3 mm long, lanceolate to trowel-shaped, bearing a tuft of hairs at the apex.
Torus
flat, 2.5-3.2 mm in diameter.
Fruit
of up to 6 glabrate monocarps borne on a pedicel 3-7 mm long, 1.2-2 mm thick, pubescent, with sepals persistent; torus 2.5-4 mm in diameter, 2.0-2.2 mm high, globose to depressed-globose.
Monocarps
with yellowish or glaucous green exterior and scarlet endocarp
in vivo
, 1.3-3.6 cm long, 0.6-1.3 cm wide, (0.5-) 0.7-1.2 cm thick, oblong, irregularly torulose, apex obtuse to acute, rarely mucronate, contracted into a stipe 3-10 mm long, 1.7-2.2 mm thick, surface pruinose, longitudinally wrinkled and finely verrucose; pericarp ca. 0.5 mm thick.
Seeds
up to 7 per monocarp, in two irregular rows, lying oblique to long axis, 9.8-12.2 mm long, 5.5-7.4 mm wide, 4.5-7.0 mm thick, pyriform, narrowed into a cylindrical neck 1.6-2.3 mm long and 2.7-3.5 mm wide toward micropyle, irregularly ellipsoid in cross section, obliquely truncate at micropylar end, rounded at chalazal end, brown, smooth, shiny, raphe/antiraphe not evident, micropylar scar 1.4-1.5 mm long, 1.0-1.1 mm wide, elliptic; sarcotesta bright orange, fleshy
in vivo
; aril absent.
Phenology.
Specimens with flowers have been collected in February, March, October, and December, and with fruits in June and from November to March.
Distribution
(Fig.
22
). Restricted to southeastern Tanzania and northeastern Mozambique, where it grows in thickets and open woodland on slopes and plateau surfaces, usu
ally
on deep white sand and less commonly on loam, often locally common on roadsides and in areas mixed with planted cashew (
Anacardium
) trees, at elevations of 200-900 m.
Local names.
Mutuka (Kimakonde,
Busse 2858
), nampemedi (Kiswahili,
Johnson & Swedi 1914
), pempantavala (Kimuera,
Schlieben 5470
; the same common name was reported by Schlieben as being used for
Popowia
(now
Monanthotaxis
)
trichantha
, see
Diels 1936
).
Additional specimens examined.
TANZANIA
.
Lindi
:
Rondo Plateau
,
Rondo Forest Reserve
, below
Forest Station
,
10°07'S
,
39°14'E
,
13 Feb 1991
(fl),
Bidgood
et al. 1535
(DSM, EA, K, NHT),
13 Feb 1991
(fr),
Bidgood
et al. 1544
(EA, K-2 sheets, MO, NHT)
;
track from
Nyengedi
to
Rondo Plateau
,
10°12'S
,
39°20'E
,
16 Feb 1991
(fl),
Bidgood
et al. 1600
(DSM, EA, K, NHT)
;
["
Nordwestliches Muera-Plateau
, etwa
600 m
ue
. M., in dichter
Buschenklave
auf sandigen
Boden
",
14 Jun 1903
(fr), ex
Diels 1936
],
Busse
2858
(EA)
;
Mchinjiri
,
Rondo Plateau
,
Nov 1951
(buds),
Eggeling
6386
(K, TFD)
;
track from
Nyengedi
(between
Masasi
and
Mnazimoja
) to
Rondo Plateau
, ca.
3 km
N of Nyengedi
,
10°14'00"S
,
39°24'00"E
,
7 Mar 1996
(fl, fr),
Johnson
&
Swedi
1906
,
8 Mar 1996
(fl, fr),
Johnson
&
Swedi
1910
(DSM, OWU)
;
Lindi District
,
Nyangamara Forest Reserve
,
10°19'S
,
39°59'E
,
10 Mar 1996
(fl, fr),
Johnson
&
Swedi
1914
(DSM, OWU)
;
Noto Plateau
,
N of Chitoa Plateau
,
09°54'S
,
39°24'E
,
8 Jul 2008
(buds),
Mwangoka
et al. 5801
(OWU)
;
Lindi District
,
Rondo Forest Reserve
,
21 Jan 1968
(fr),
Shabani
43
(EA, TFD)
;
Lindi
Rural District
,
Mtama Division
,
Namiupa Ward
,
Rondo Forest Reserve
,
NW of Mihima Village
,
10°12'19"S
,
39°09'21"E
,
640 m
,
3 Nov 2005
(fr),
Simon Laizer
et al. 1352
(OWU)
.-
Mtwara
:
Newala District
,
Mahuta
,
16 Dec 1942
(buds),
Gillman
1055
(EA, K)
;
Mnima
,
23 Mar 1943
(fr),
Gillman
1293
(K)
;
Newala District
, road from
Mtama
to
Mkwiti
, ca.
2 km
N of Mkwiti
,
10°03'S
,
40°11'E
,
10 Mar 1996
(fl, fr),
Johnson
&
Swedi
1913
(DSM, OWU)
.
MOZAMBIQUE
.
Cabo Delgado
:
Palma area
, on old western road to
Quionga
,
10.8 km
from the roundabout at the white church,
10°40'49"S
,
40°26'11"E
,
60 m
,
12 Mar 2008
(fl buds),
Burrows
&
Burrows
10942
(K)
;
Palma area
,
1 km
E of Muangaza
S of
Palma
,
10°55'25.5"S
,
40°23'34.8"E
,
65 m
,
5 Dec 2008
(fr),
Goyder
et al. 5084
(K)
;
Nanhamba
,
7 km
S of Mocimboa do Rovuma
,
11°19'27"S
,
39°18'55"E
,
573 m
,
10 Sep 2009
(fr),
Loetter
&
Turpin
1882
(K)
;
Mueda Plateau
,
11°24'S
,
39°23'E
,
860 m
,
12 Dec 2003
(yg fr),
Luke
et al. 10039
(K, MO)
;
Niassa
,
Chomba
, entre o cruzamento e
Chomba
,
20 Sep 1948
(st),
Pedro
&
Pedrogao
5279
(EA)
;
Palma District
,
Miculumo area
,
10 km
NW of Palma
,
10°40'39.9"S
,
40°25'08.9"E
,
56 m
,
6 Dec 2008
(fl),
Timberlake
et al. 5640
(K)
.
The red flowers of
Xylopia collina
are unusual in the genus and, coupled with the shrub habit, the long erect hairs on the twigs and leaves, and the pruinose surface of the dried monocarps, make it a distinctive and easily recognized plant. With the examination of more extensive material, we do not maintain
Xylopia latipetala
Verdc. as a distinct species. The
type
specimen,
Milne-Redhead and Taylor 7617
, does indeed bear flowers with sepals and petals broader than in the
type
specimen of
X. collina
, but the gap in sizes presented in
Verdcourt's
(1971a)
description has now been filled by
additional specimens
:
Bidgood et al. 1535
, for example, has flowers with the outer petals
4.9-6.9 mm
wide, i.e. intermediate in size between the two described species. We
also
observed considerable variation in petal size and shape within field populations of
X. collina
, suggesting that variation in petal size is a normal attribute of this species.
Although the flowers emit an ester/vinegar scent of rotting fruit during the middle of the day, suggesting small flies, nitidulid beetles, or thrips as possible flower visitors, no pollinators were found. Color cues may be important in determining the timing of pollinator behavior, as the flower buds are initially white, then become pink or pinkish orange, and finally turn pinkish red. The tips of the petals often become black or dark gray. A band of corrugated tissue crosses the adaxial surface of the inner petal at its widest extent and may provide a food reward for pollinators. As in
X. arenaria
, onset of anthesis is signalled by the bending of the apices of the inner petals so that they emerge through the gaps between the erect outer petals.
Associates observed at several sites included
Bosqueiopsis gilletii
,
Milicia excelsa
,
Grewia conocarpa
, and species of
Albizia
,
Heinsia
,
Hymenocardia
,
Indigofera
,
Mimosa
, and
Pteleopsis
. In the area of a recent burn on the Rondo Plateau in March, 1996,
Xylopia collina
was one of several
Annonaceae
, including also
Dielsiothamnus divaricatus
,
Monanthotaxis buchananii
,
Monodora minor
, and
Uvaria acuminata
, observed to be regenerating from a rootstock after fire. The indurated black bud scales on the vegetative buds may play a role in allowing shoot regeneration after fire or drought; such bud scales are unusual in
Annonaceae
, where dormant shoot tips are typically naked. The growth of
X. collina
also exhibits distinctive stem galls (Fig.
20F
) that are seen in other African species of
Xylopia
.
There are four sheets of the type collection,
Schlieben 5470
, at B. None is in exact agreement with the protologue concerning the type locality, but the sheet with detail drawings of the floral parts attached is chosen as the
lectotype
.
As shown in Table
1
, the AOO for this species was relatively high (
76 km
2) for the size of its EOO (
12,374 km
2). We found
X. collina
to be locally frequent along roadsides, which may make it more frequently collected. In the IUCN Red List (version 3.1), it has been classified, however, as Endangered, largely due to the small size of its global distribution and local habitat alteration.
A decoction of the leaves of
Xylopia collina
was reported by local informants in the Nyangamara region of southern
Tanzania
to be used as a treatment for hernia.