The genus Disperis (Orchidaceae) in Madagascar, the Comores, the Mascarenes and the Seychelles
Author
Croix, Isobyl la
Author
Bosser, Jean
Author
Cribb, Phillip J.
text
Adansonia
2002
3
24
1
55
87
journal article
http://doi.org/10.5281/zenodo.5180356
1639-4798
5180356
9.
Disperis ankarensis
H. Perrier
Not. Syst. (Paris) 8: 129 (1939)
; in Humbert H.
(ed.), Fl. Madag., 49
e
fam.,
Orchidées 1: 186 (1939)
;
Fig. 6. — Appendage of lip:
A
,
Disperis majungensis
(
Perrier de la Bâthie 13038
);
B
,
Disperis cordata
(
Cadet C11, in alcohol
);
C
,
Disperis hildebrandtii
(
Hildebrandt 3158
);
D
,
Disperis ciliata
(
Humbert & Capuron 25002
);
E
,
Disperis lanceana
(
Lance s.n
.);
F
,
Disperis saxicola
(
Bosser 17168
);
G
,
Disperis humblotii
(
Humblot 1592
)
;
H
;
Disperis perrieri
(
Humbert & Capuron 25758
);
I
,
Disperis oppositifolia
var.
mascarenensis
(
Bosser 21622
).
Fig. 7. — Flowers of
Disperis
species
:
A
,
D. hildebrandtii
;
B
,
D. saxicola
;
C
,
D
.
discifera
;
D
,
D. oppositifolia
var.
oppositifolia
;
E
,
D. oppositifolia
var.
mascarenensis
;
F
,
D. masoalensis
. (A, D, F, photos J.-N. LABAT; B, C, E, photos J. BOSSER).
mm 1
E
Fig. 8. —
Disperis ankarensis
: A
, flowering plant;
B
, flower;
C
, hood, side view;
D
, dorsal sepal;
E
, lateral sepal;
F
, petal;
G
, column and lip, front view;
H
, column and lip, back view;
I
, column and lip, side view;
J
, pollinarium;
K
, lip. (
Humbert 18986,
P).
Du Puy
et al.,
Orch. Madag.
: 133 (1999)
. —
Type
:
Humbert 18825 (= Humbert 18986),
Madagascar
, Ankarana,
N
of
Ambilobé
,
Jan. 1938
(holo-,
P
!, photo
K
!). Known only from the
type
collection
.
Slender terrestrial herb
14-18 cm
high. Tubers 2, up to 2 ×
1.2 cm
, ovoid, villous. Leaves 2, in the upper half of the stem, alternate, 3.5-5 ×
0.5-1 cm
, narrowly lanceolate or linear-lanceolate, forming a funnel-shaped sheath at the base that clasps the stem. Inflorescence 1-3-flowered; bracts leafy, 18-32 ×
3-4 mm
. Flowers with green sepals, veined with pink, petals pink; pedicel and ovary
8-9 mm
long. Dorsal sepal
8 mm
long, linear, forming with the petals a broad, very concave hood c.
8 mm
high and
15 mm
wide; lateral sepals 7 ×
3 mm
, joined near the base, falcate, the tips curling in, each with a sac-like spur in the basal half. Petals hyaline. Lip erect part joined to the column for most of its length with only a short free part; appendage 3-lobed; mid-lobe
3.5- 5 mm
long, fleshy, tongue-shaped, rounded at the apex, slightly sigmoid in profile, not stalked, carrying long hairs on the upper surface and short papillae beneath; side lobes
2-3 mm
long, linear-oblong, glabrous or with short papillae on the upper surface, arching and curving to the side, narrower than the mid-lobe and twisted at the tips. Rostellum lobes very broad and thick with hyaline, spathulate arms, twisted and geniculate at the base. —
Fig. 8.
NOTE. —
The
description given in the
Flore
de
Madagascar
does not seem to match the drawing on the
type
sheet (which is described here)
.
DISTRIBUTION. —
Madagascar
; endemic.
HABITAT. — Terrestrial in semi-dry forest of the W, growing in the humus amongst calcareous rocks; c.
300 m
.
This species is only known from the
type
. The flower shows affinities with
D. hildebrandtii
but it is distinguished readily by the nature of the hairs of the terminal appendage of the lip.
PERRIER DE LA BÂTHIE, in his protolog, cited a single specimen (
Humbert 18825
). However, the only specimen at P is
Humbert 18986
with the same locality and date. There is a single collection as can be seen from the fact that HUMBERT’ s field