Revision of the group previously known as Panicum L. (Poaceae: Panicoideae) in Madagascar
Author
Vorontsova, Maria S.
text
Candollea
2018
2018-11-05
73
2
143
186
journal article
20513
10.15553/c2018v732a1
025e1235-99de-4ef9-8849-de54ad29a779
2235-3658
5724514
6.
Panicum capuronii
A. Camus in
Bull. Soc. Bot.
France
103: 613. 1957
(
Fig. 5
).
Lectotypus
(designated here):
MADAGASCAR
.
Prov. Toliara
:
forêt d’Iera
à env.
30 km
W d’Ankazoabo
,
IV.1955
,
Humbert
29717
(
P
[
P00450282
]!;
isolectotype
:
P
[
P00450283
]!)
.
Delicate annual, erect,
5– 15 cm
tall, the culms glabrous with some cilia at the nodes.
Leaf sheaths
pilose on the margins.
Ligule
a ciliolate membrane.
Leaf blades
elliptic, flat, membranous, cordate and amplexicaul at base, 2.5–5 ×
0.5–0.9 cm
, drying yellow-green, glabrous on both sides.
Panicles
terminal, fully exserted,
3–6 cm
long, linear, the branches lax, ascending, with glandular patches, glabrous.
Spikelets
ovate, asymmetric, apically obtuse, c.
1.5 mm
long, green, opening only partly.
Lower glume
equalling or slightly exceeding the spikelet, membranous, acute, 1–3-veined, glabrous to pubescent, separated from the rest of the spikelet by a short internode.
Upper glume
as long as the spikelet, herbaceous, 5-veined, hirsute with bulbous-based trichomes c.
1 mm
long at maturity.
Lower floret
male, with a fully developed palea.
Lower lemma
thinly cartilaginous, 5-veined, sometimes hooded, glabrous.
Upper lemma
with sparse minute elongated verruccae towards the upper half, often dehiscing before the lower floret.
Distribution and ecology
. – Endemic to
Madagascar
. Shade understory of seasonally dry forest, c.
400 m
(
Fig. 2B
).
Notes
. – Known from the
type
collection only.
Close to
P. subhystrix
but differs by the shape of the verrucae on its upper lemma which are sparse and elongated, not rounded.
Panicum subhystrix
occupies a different environmental niche of higher elevation rocky and savanna habitats on the High Plateau.
Brachiaria capuronii
A. Camus
has a short lower glume and spikelets arranged along racemes, and is a different species likely not directly related to
Panicum capuronii
. Confusion is possible since
Brachiaria capuronii
has broad membranous leaves somewhat similar to those of
Panicum capuronii
and comes from a similar area of
Madagascar
.