Talinella pachypoda Eggli

Applequist, Wendy L., 2005, A revision of the Malagasy endemic Talinella (Portulacaceae), Adansonia (3) 27 (1), pp. 47-80 : 74-75

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) .

Figures

FIG. 4. — Distributions of Talinella species from the extreme north: T. ankaranensis (●), T. boiviniana (▲), T. pachypoda ($).