A revision of the endemic Malagasy genus Beguea (Sapindaceae)
Author
George E. Schatz
Africa and Madagascar Program, Missouri Botanical Garden, P. O. Box 299, St. Louis, MO 63166 - 0299, U. S. A.
george.schatz@mobot.org
Author
Roy E. Gereau
Africa and Madagascar Program, Missouri Botanical Garden, P. O. Box 299, St. Louis, MO 63166 - 0299, U. S. A.
Author
Porter P. Lowry Ii
Africa and Madagascar Program, Missouri Botanical Garden, P. O. Box 299, St. Louis, MO 63166 - 0299, U. S. A. and Institut de Systématique, Evolution, et Biodiversité (UMR 7205 - CNRS MNHN UPMC EPHE), Muséum national d’Histoire naturelle, Sorbonne Universités, C. P. 39, rue Cuvier 57, 75231 Paris CEDEX 05, France
text
Candollea
2017
2017-03-30
72
1
45
65
journal article
32147
10.15553/c2017v721a6
c05afdbe-5c00-406f-abf5-69a53d227a8b
2235-3658
888177
3.
Beguea australis
G.E. Schatz, Gereau & Lowry
,
spec. nova
(
Fig. 5
).
Typus
:
MADAGASCAR
.
Prov. Toliara
:
Anosy Region
,
RNI Andohahela
,
Parcelle 1
,
Ambahibe
,
Isaka Ivondro
,
24̊47’S 46̊50’E
,
0-500 m
,
10-27.IX.1993
,
fr.,
Randriamampionona
633 (
holo-
:
MO-6641487!
;
iso-
:
BM
!,
C
!,
CAS
!,
E
!,
G
[
G00341687
]!,
K
!,
L
!,
M
!,
NY
!,
P
[
P00580343
]!,
PRE
!,
TAN
!,
UPS
!,
US
!).
Haec species a congeneris foliolis ad apicem retusis usque profunde emarginatis atque fructu lignoso mesocarpio 3-4.7 mm crasso distinguitur.
Tree
to 20 m tall, bole c. 20 cm in diam.; stems densely light reddish tan tomentose.
Petioles
7.5-10 cm, densely light reddish tan tomentose.
Leaves
with 12-30 alternate to subopposite leaflets; rachis 18-21 cm, densely light reddish tan tomentulose, not keeled; petiolule 2-7 mm, densely light reddish tan tomentulose; leaflet blade 4.6-12.6 × 2.4-4.4 cm, elliptic to narrowly obovate, chartaceous to subcoriaceous, flat in pressed material, glabrous and somewhat glossy and verrucose above, initially reddish tomentulose below, glabrescent or indument persistent close to the midvein below, base asymmetrical, cuneate to attenuate and decurrent along petiolule, margins flat, apex retuse to deeply emarginate, the notch to 1 cm deep and often with straight sides (“v ”-notched), midvein flat to raised towards the base above, initially densely light brown tomentulose, glabrescent, distinctly raised below, persistently light reddish brown tomentulose, secondary veins 8-13 per side, slightly raised above and below, initially reddish tomentulose below, glabrescent, tertiary venation slightly raised above and below.
Flowers
unknown.
Infructescence
axis 5.6-15.4 cm long, 2.8-3.5 mm in diam., unbranched, densely light reddish tan tomentose; pedicels in fruit 3-4 mm, c. 1.1 mm in diam., reddish tomentulose.
Fruit
ellipsoid, 1.4-3.1 cm long, 1.1-2.3 cm in diam, glabrous, apex acute and slightly curved, sometimes with an apiculum to 1 mm, mesocarp (fruit wall) 3-4.7 mm thick, rendering the fruits hard and woody; seed flattened ellipsoid, 5-17 × c. 13 × c. 12 mm.
Etymology. –
The epithet
australis
refers to the southernmost occurrence of the genus
Beguea
in Madagascar.
Conservation status
. – Despite the very restricted Area of Occupancy within well-protected Andohahela National Park (
Fig. 4
), there appear to be no current threats, and thus
Beguea australis
is assigned a status of “Least Concern” [LC] using the IUCN Red List Criteria (
IUCN, 2012
), with the caution that this status is highly dependent on continued effective protection.
Fig. 5. –
Begueo
oustrolis
G.E. Schatz, Gereau & Lowry.
A.
Fruiting
branch;
B.
Leaflet (lower surface);
C.
Leaflet (upper surface);
D.
Fruit (with close-up of surface);
E.
Section of fruit. [
Rondriomompionono 633
, MO] [Drawing: R.L. Andriamiarisoa]
Notes
. –
Beguea australis
is known from only two collections made in humid forest at Andohahela National Park (
Fig. 4
). It can be easily recognized from all other species of
Beguea
by its large leaves with 12-30 leaflets whose apex is usually deeply emarginate, and its large woody fruits with a wall 3-4.7 mm thick (
Fig. 5
).
Paratypi
. –
MADAGASCAR
.
Prov. Toliara
:
Anosy Region
,
RNI 11
,
Andohahela
,
Parcelle 1
,
Isaka Ivondro
,
24̊40’S 46̊52’E
,
100-500 m
,
12-23.VI.1993
,
fr.,
Randriamampionona
454 (
BM
,
G
,
K
,
MO
,
NY
,
P
,
TAN
,
US
).