Rhodolaena altivola Thouars

Schatz, George E., Lowry Ii, Porter P. & Wolf, Anne-Elizabeth, 2000, Endemic families of Madagascar. VI. A synoptic revision of Rhodolaena (Sarcolaenaceae), Adansonia (3) 22 (2), pp. 239-252 : 243

2. Rhodolaena altivola Thouars

Hist. Vég. Iles Austr. Afr. 47, pl. 13 (1805).

TYPE. — Thouars s.n., Madagascar, without precise locality (holo-, P!) .

Rhodolaena altivola is a small tree occurring in low to mid-elevation humid forest along the north-central part of the east coast ( Fig. 1 ). A single specimen with locality data indicating “Didy”, situated farther inland, was probably in fact collected much nearer to the coast. This species is distinguished by large, ovate, coriaceous leaves with an acuminate apex and more or less rounded base (closely resembling those of Schizolaena laurina Baill. ), and glabrous, shiny sepals. As in R. acutifolia , the leaves dry maroonbrownish, the secondary veins are usually obscure on the dull upper surface, and the tertiary veins form a dense reticulated network on the lower surface. Rhodolaena altivola has recently been collected at Analalava west of Foulpointe, and at Tampolo STF.

MATERIAL EXAMINED. — Catat 1726, Didy; d’Alleizette 539, Baie d’Antongil; Andrianjafy 85, Analalava; Humblot 215, without precise locality; Raholivelo 22, Tampolo STF; Rakotozafy 1438, 1438bis, Analabe; Service Forestier 28891, Antetezana, 33539, Analalava; Thouars s.n., without precise locality.

Figures

Fig. 1. — Distributions of Rhodolaena, mapped on the bioclimatic zones of Madagascar (after CORNET 1974; see SCHATZ 2000). R. acutifolia (•), R. altivola (*), R. bakeriana (Δ), R. leroyana (-).