Novitates gabonenses 13. Three new species and one new combination in Combretum (Combretaceae)

6 Pages·1992·2.8 MB·

by  C C H Jongkind

258
cm
1
1cm
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1mm
I
I
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I
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cm
1
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mm
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1
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J
1m
m
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m
m
25^
2S)A
mm
1
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G
K
\
L
— —
Combretum
robustum
Fig. 1. A, leaf; B, flower; C, scale from above. Combretum rabiense D, leaf; E, flower;
—
:
:
F, flower cut length wise, petals and three stamens removed G, scale from above. Combretum ivanii H, leaf; J,
; :
domatium, hairs removed; K, flower; L, scale from above.
;;
259
mm
fragrant. Receptacle greenish, covered by grey brown
to hairs lower
receptacle long
ca.
; 1
mm
mm
upper
receptacle 4-6 long and
2 wide, long
ca. infundibuliform, hairy Calyx
inside.
mm
lobes not conspicuous. Petals spatulate, obscure up to long, glabrous. Stamens
2-seriate,
1
4mm
3mm
0.5mm
ca. exserted, yellow; anthers
ca. long. Style
ca. exserted, glabrous. Disc'
inconspicuous. 5.5cm
Fruit ca. in diameter, with papery wings, glabrous; up 2cm
stipe to
long.
—
Material Gabon
examined.
de Wilde
—
:
WAG
Central African Republic
type). Eq. Tisserant
; :
WAG)
WAG)
P, Eq. Tisserant 1626, Boukoko, Oct.
(P,
fl.,
;
WAG)
BR,
Boukoko,
A, P, Eq. Tisserant 2445, Febr.
fr. juv.,
;
(BM
—
&
Note. Combretum Combretum
In flower robustum resembles auriculatum Engl.
Diels,
but this second species has wingless fruits, in contrast with the large winged fruits of the new
species. There
are small differences in the shape of the petals and the receptacle between the collections of the
two
different localities, but the similarities are so dominating, that they almost certainly belong
same
to the
species.
—
Combretum
D-H;
rabiense Jongkind,
sp. nov. Fig. Fig. B.
2,
1,
Liana magna.
Folia papyracea
elliptica in vivo vel coriacea, in sicco papyracea, venis majoribus
Inflorescentiae
ifl
Receptaculum
viride, basi velutinum. Receptaculum superius campanulatum. Lobi calycis deltoidei. Petala
obovata
ciliata aliter glabra alba. Stamina exserta, filamentis flavescentibus, antheris luteis. Stylus exsertus
glaber. Fructus immaturus
glaber.
&
Type
Breteler, Jongkind, Mossavou Wieringa 9807, Gabon, Rabi oil-exploitation area, juv.,
fl., fr.
:
WAG:
March (holo-, BM. BR. K. LBV. M. MO. PV
iso-.
m
cm
Liana up
to 40 long. Branchlets velutinous. Petiole up to long. Leaves up
elliptic,
1
x
to 20 10 cm, papery to leathery, puberulous on the larger veines, otherwise glabrous on both
sides; 6-9 pairs of main lateral nerves, domatia inconspicuous, tertiary nervation almost
parallel; base attenuate; apex acuminate, mucronate. Scales circular, 50-65 \im in diameter,
with embedded
ca. 8 thick-walled usually in a glutinous exudate. Inflorescences axillary
cells,
and cm
up
terminal, 4 Leaves subtending
rachis to long, velutinous. the inflorescence greenish-
mm
white. Bracts 2 puberulous. Flowers 4-merous, protogynous. Receptacle
ca. long, sessile,
green; lower 1.5mm upper campanulate,
receptacle long, angular, velutinous; receptacle
ca.
x mm, mm,
x
3.5 3 puberulous. Petals obovate, 1.5-2 1.2-1.5 ciliate otherwise glabrous, white.
5mm
0.7mm
Stamens
1-seriate, ca. exserted; filaments yellowish-white; anthers ca. long,
mm
yellow. Disk glabrous except for the ca. wide edge that covered with long hairs, this
is
1
mm
cm
edge Immature
hides the insertion of the stamens. Style ca. 3 exserted, glabrous. fruit 3
long, winged,
glabrous.
—
o
Material Gabon Waka,
examined. Arends al near the "Falaise", 18'S-10°57'E,
et 428,
l
:
WAG);
altitude 380m, Nov. (LBV, Breteler et 9807, Rabi oil-exploitation area, ca. 1°54' S-9°53' E,
al.
fl.,
260
—
Fig. 2. A, Distribution of Combretum robustum B, Distribution of Combretum rabiense C, Distribution of
Combretum
ivanii.
261
March (BM, BR, LBV, M, MO, WAG; &
juv., K, km
fl., fr. P, type); de Wilde Jongkind 9617, 48 along
road Doussala-Bongo, WAG);
forest ca. 2°15'S-10°25'E, 270m, March (LBV, Le 8224
alt. Testu
fl.,
&
Moucwala,
1°23'S-12 14'E, Aug. (BR, P); Louis Nzabi Ngounie
fl., 3000, Prov., forest road near
Bilengui, ca. 1°55'S-11 25'E, altitude 300-400m, (LBV, WAG).
juv., April
fl., fr.
—
Note. For
a long time this species has been confused with Combretum sordidum
Exell,
with which has much common. The most
it in obvious differences of C. sordidum with the new
species are the narrower and glabrous and The
petals the longer anthers. rich collection of the
new
species that was made in the Rabi area first made clear that there existed a neglected
it
second mixed up
species with C. sordidum, therefore Combretum
this species called
rabiensis.
is
—
Combretum
Jongkind,
ivanii sp. nov. Fig. J-L; Fig. C.
1, 2,
Liana magna.
Folia anguste ovata glabra sed aliter domatiis profulta, basi rotundata usque ad
attenuata, apice longe acuminata.
Inflorescentiae axillares et terminales, rhachidibus puberulis. Folia
inflorescentias subtentes angusta et viridule alba. Bracteae lineares. Flores tetrameri sessiles odorantes.
Receptaculum
lepidotum. Receptaculum superius cupelliforme Lobi calycis inconspicui Petala
acuti.
.
Stamina
absentia.
exserta, filamentis albis, antheris cordatis apiculatis luteis. Stylus exsertus glaber. Fructus
ignotus.
R
Type Nek
van 488, Gabon, Rabi-Kounga area, Pipeline track near the Rabi compound, Dec.
fl.,
:
WAG;
MO,
LBV,
(holo-,
iso-, P).
woody cm Wood
Large liana. Branches up to 2 diameter. with a transparent sticky
cm
exudate. Petiole up to long. Leaves narrowly ovate, up to 12 x 6 cm, glabrous except for
1
the domatia 4-7 pairs of main lateral nerves with hairy pit domatia, tertiary nervation almost
;
parallel base rounded to attenuate apex long acuminate. Scales circular to shallowly lobed,
; ;
45-90
jxm in diameter, with usually thick-walled probably glandular. Inflorescences
8 cells,
and cm
axillary terminal, rachis up to 5 long, puberulous. Leaves subtending the inflorescence
mm
narrow
and
greenish -white. Bracts ca. long, linear. Flowers 4-merous, sessile, protogy-
1
mm
nous,
fragrant. Receptacle covered by a contiguous layer of scales lower receptacle long
1
;
mm
1.5mm
angular; upper receptacle cupuliform, high and wide, hairy inside. Calyx lobes
1
2mm
not
conspicuous, acute. Petals absent. Stamens ca. exserted; filaments white; anthers
mm mm
cordate, ca. 0.3 long, apiculate, yellow. Style ca. 1.5 exserted, glabrous. Disc hairy.
unknown.
Fruit
—
Material Gabon Nek Rabi compound,
examined. van 488, Pipeline track near the ca. 1°54'S-
:
WAG;
MO,
9°53'E, Dec. (LBV,
P, type).
fl.,
—
Note. By the very small flowers with a cupuliform upper receptacle and the absence of
The named
petals this species can be easily distinguished from others. species is after its
collector Ivan van Nek.
(Welwitsch
Quisqualis falcata Welwitsch ex Hiern, Cat. Afr. Welw. 355 (1898). Type Welwitsch 4348,
PI.
1
: :
BM;
BR,
Angola, Cuanza Norte, Golungo Alto, between Sanga and Bango, (holo-, iso-,
fr.
fl.,
K,
P).
262
&
Combretum Engler Monogr.
— mussaendiflorum Diels, afr. Pflanzen. 3 87, tab. 25e (1899).
:
&
Quisqualis mussaendiflora (Engler Diels) Exell, Journ. of Botany 69 121 (1931). Type
: :
Deschamps Zaire, Mtowa, June anno 1895 (holo-, BR).
s.n.,
fl.,
&
Combretum Engler Monogr. Type
sericogyne Diels, afr. Pflanzen. 3 87 (1899). E. Laurent s.n.,
: :
Lusambo,
Zaire, Dec. (holo-, BR).
fl.,
Combretum
pellegrinianum Exell, Journ. of Botany 67 177
— (1929), syn. nov.
:
Quisqualis pellegriniana (Exell) Exell, Journ. of Botany 69 121 (1931) (not sensu Keay,
W
:
Flora of Trop. Afr., sec. ed. 1 (1) 275 (1954) Talbot 498 is not this species but Grif-
: :
fonia physocarpa Baill., a Caesalpinioideal). Type de Brazza Gabon, Ossiga,
J. 83,
fl., fr.
:
BM;
(holo-, iso-, P).
C
Cacoucia littorea Engler, Pflanzenwelt Ost-Afrikas und der Nachbargebiete, 293 (1895), syn.
:
nov.
—
Quisqualis littorea (Engler) Exell, Journ. of Botany 69 121 (1931). Type Volkens 147,
: :
Tanzania, Tanga, fl., fr., Febr. (syn-, B delet. lecto-, designated here, BR; iso-, BM, E, K);
;
HBG,
B B
Hoist 2061, fl., fr., Jan. (syn-, delet,; iso-, K); Hoist 4034 (syn-, delet.).
Note The new
addition of two synonyms does not really expand the variation of this
:
species, only the ultimate dimensions of the flowers are somewhat extended.
REFERENCES
—
Jongkind, C. C. H., 1990 (publ. 1991). Novitates gabonenses Some observations on
6. critical
Combretum
versus Quisqualis (Combretaceae) and description of two new of Combretum.
species
Mus.
Bull. natn. Hist, nat., Paris, 4e ser., 12, sect. B, Adansonia, nos 3-4 275-280.
:
Mus.
Bull. natl. Hist, nat., Paris, 4 C 1992
ser., 14, (publ.
1993),
section B, Adansonia, n° 2 263-278.
:
Anatomie
florale des Culcasia (Araceae)
&
D. Barabe Forget
S.
Resume
Les
auteurs analysent la vascularisation florale de quatre especes de Culcasia
(C.
:
C
piperoides, C. saxatilis scandens et C. striolata) en vue de comprendre nature des gynecees
la
t
pseudo-monomeres dans La
ce genre. vascularisation florale des Culcasia presente peu de
similitudes avec celle des Philodendron. Ces donnees sont discutees en rapport avec
la
Grayum.
classification des Araceae proposee par
Summary
The
authors analyse the floral vascularization of four species of Culcasia (C.
:
piperoides, C. saxatilis C. scandens and C. striolata) to better understand the nature of
t
pseudomonomerous
The
gynocia in this genus. floral vascularization of Culcasia presents few
similarities with that of Philodendron. These facts are discussed in relation of the classification of
the Araceae proposed by Grayum.
as
Denis Barabe et Suzanne Forget, Institut de recherche en biologie vegetale, Jardin botanique de
H1X
Montreal 4101, rue Sherbrooke Montreal (Quebec) 2B2, Canada.
est,
\
INTRODUCTION
Les caracteres floraux representent un element important dans classification des sous-
la
$
compte (Grayum,
families et des genres Araceae, famille qui 107 genres et 2 500 especes
A
1990). cause de grande d'un genre a Fautre, des Araceae prete
sa variability la fleur se tres
rpholo
Eyde
A
Hotta
1986c) et (1971). partir de leurs analyses, ces auteurs ont deduit des considerations
phylogeniques importants pour
et fait ressortir certains caracteres la classification infra-
Grayum
Recemment
familiale. a une synthese de Involution des caracteres
(1990) realise
floraux en rapport avec phylogenie.
la
Depuis plusieurs annees, une etude anatomique des caracteres floraux de differents genres
& &
Barabe Labrecque,
Araceae a au Jardin botanique de Montreal 1984;
ete entreprise, (e.g.
&
Barabe Barabe Forget, dans but de comprendre revolution de
et 1986, 1987; 1988), le
al.,
pseudo-monomeres que Fon rencontre frequemment dans
la fleur et la nature des gynecees
cette famille. Ces gynecees representent un cas typique de reduction de Fappareil reproducteur
Par pseudo-monomere nous entendons un gynecee syncarpe qui ne semble
femelle. gynecee
compose
superficiellement que d'un seul carpelle.
Eckardt que Araceae presentaient plusieurs cas de pseudo-
(1937) insista sur le fait les
%
monomerie. Dans de 40 des genres possedent des gynecees uni-loculaires
pres
cette famille,