A revision of the Malagasy endemic Talinella (Portulacaceae)
Author
Applequist, Wendy L.
text
Adansonia
2005
3
27
1
47
80
journal article
http://doi.org/10.5281/zenodo.5370864
1639-4798
5370864
10.
Talinella pachypoda
Eggli
Adansonia, sér. 3, 19: 57 (1997)
. —
Type
:
Röösli
&
Rechberger
s.n.
,
Madagascar
, Diégo Suarez,
Montagne des
Français
, SE flank,
7-8 km
from Diégo Suarez (
c.
12°19.5’S
,
049°20’E
), 1989 (holo-,
ZSS
)
.
Shrub to
3 m
, usually with arching branches, sometimes with short thick trunk or basal caudex; rarely described as a small tree. Twigs straight to contorted, brown to reddish brown; lenticels on large twigs pale, elliptical to round, occasionally absent; smallest twigs frequently papillose with brown and white papillae. Leaves elliptical, 2.5- 7.0 cm long, 1.00-
2.75 cm
broad; apex apiculate, occasionally acute or emarginate, usually symmetrical; base tapering; margins entire, slightly wavy, minutely papillose; blade membraneous or papery when dried, sometimes possibly paler around midrib and secondary veins above; under surface sometimes reddish tinged; midrib conspicuous at least on lower surface, higher-order venation observable. Often leafless at time of flowering. Inflorescences unisexual, plants probably dioecious. Inflorescences lateral or terminal, with up to a dozen fertile flowers; peduncle and rachis white-papillate; bracts
c.
(0.3-)
0.5-1.6 mm
long, narrowly to broadly triangular, reddish to brown, often with a pale apex. Pedicel
1.5-5 mm
long. Sepals (1.7-)2.0-3.0 mm long, orbicular, sometimes unequal. Petals (3-)5, (2.0-)
2.5- 3.5 mm
long, pink-tinged white to rose, sometimes irregularly shaped or orbicular due to fusion of 2 petals, otherwise oblong to elliptical. Filaments connate at base and attached to ring- shaped nectary disk,
1.5-2.5 mm
long, white or pinkish, the bases barely ciliate; anthers yellow, 0.40-0.60(-0.85) mm long. Stigma branches 2-3, white, 1.0-
1.5 mm
long, flattened, with papillose or ciliate edges, sessile in developing fruit, sometimes on very short broad style; ovary green, ovoid. Fruit ovoid to pyriform or oblong, with a pronounced apical beak, sometimes a capsule apically dehiscing by 2-3 shallow valves, to
8 mm
long, up to 6-seeded; sepals and frequently petals persistent; pedicel sometimes thickening slightly in fruit; immature seeds elliptical to orbicular, possibly with a shallow ridge around edge.
Few fruiting specimens of
Talinella pachypoda
exist. The fruits, which are ovoid with a prominent apical nipple for most of their development, have been described as berries (
EGGLI 1997
). However,
one specimen
(
Jongkind & Rapanarivo 969
, MO) has mature fruits that are clearly capsular, apically dehiscent with thin dry walls. An error could easily have been made if only unripe fruits were available; for example, CAVACO (1952) described the globose circumscissile capsules of three Malagasy species of
Deeringia
as berries (APPLEQUIST & PRATT in press). If mature fleshy berries have indeed been observed, then “
T. pachypoda
” as presently defined must include a second unrecognized species. This observation suggests that
T. pachypoda
may occupy a basally branching position within
Talinella
, retaining both the usual petal number (five) and the dry fruit
type
of the genus’ nearest relatives in
Talinum
.
DISTRIBUTION. —
Talinella pachypoda
occurs in northern
Madagascar
, from Ankarana to the vicinity of
Antsiranana
(
Fig. 4
), on calcareous substrates including tsingy.
CONSERVATION STATUS. — Provisional IUCN Red List Category: Vulnerable (VU D2). No more than five clearly separate locations are known and the area of occupancy is estimated at
20 km
2
. Moreover, the number of mature individuals of
Talinella pachypoda
in the wild may be <1000, as the plant seems to be scarce in at least some of the known localities.
MATERIAL EXAMINED. —
MADAGASCAR
: Prov.
Antsiranana
:
Bardot Vaucoulon 481
, calcaires lapiazés,
massif
de l’Ankarana
, fl., fr., leaf,
15 Jan. 1991
(
P
);
Decary 14555
, massif
de l’Ankara
, roches calcaires
,
fl.,
25 Jul. 1939
(
P
);
Gentry 11943
, road along coast from Diégo-Suarez to Ramenz [= Ramena], rocky hills overlooking sea, near sea level,
23 May 1974
(
P
);
Jongkind
&
Rapanarivo
969
,
Ankarana Reserve
near
Campement des Anglais
, open forest on calcareous plateau with many small succulent Euphorbias,
c.
4 km
S
of
Campement des Anglais
,
12°54’42”S
,
049°06’43”E
,
240-260 m
,
fl., fr., leaf,
22 May 1993
(
P
,
MO
);
Phillipson 1993
, Ankarana, along RN6
30 km
N
of
Ambilobe
,
12°57’S
,
049°08’E
,
120 m
,
fl.,
30 Jun. 1987
(
P
,
MO
,
TAN
)
;
Razafimandimbison
&
Andrianantoanina
97a
,
District d’Ambilobe
,
Canton
de Mahamasina
,
N
de
Mahamasina
,
Réserve Spéciale d’Ankarana
, route
de la Grotte
des chauvessouris,
12°58’S
,
049°08’E
,
50 m
, fl., leaf,
15 Jun. 1995
(
MO
)
;
Service Forestier
22678
,
Plateau
calcaire
de l’Ankarana
, à l’W
de Mahamasina
(Antanatsimanja),
12°57’S
,
049°08’ E
, fl.,
23 Apr. 1963
(
TEF
)
.