Corresponding author: Jean-François Butaud (
Academic editor: D. Nickrent
Sandalwoods encompass 19 species restricted to southeast Asia and the Pacific. The species
Butaud J-F (2015) Reinstatement of the Loyalty Islands Sandalwood,
Sandalwoods are shrubs or small trees well known for the essential oil extracted from their fragrant heartwood and used in perfumery. They belong to the genus
The most recent taxonomical work on
Since that revision, several studies have shown the great morphological variations of
Loyalty Islands: large seeds (L = 8–11 mm, D = 7–10 mm), short and wide juvenile leaves (L = 30–52 mm, W = 8–15 mm);
Isle of Pines: medium-sized seeds (L = 8–10 mm, D = 6–9 mm), long and narrow juvenile leaves (L = 25–76 mm, W = 2–10 mm);
Grande-Terre: small seeds (L = 6–9 mm, D = 5–7 mm), long and very narrow juvenile leaves (L = 52–70 mm, W = 2–4 mm).
No comprehensive study of the variation of these characters is available in Vanuatu due to lack of herbarium specimens from most of sandalwood populations there.
For this reason,
More recently, molecular studies of New Caledonian sandalwood showed strong genetic differentiation between islands and led to the recognition of two evolutionarily significant units, i.e. Grande-Terre and Isle of Pines for the first, and Loyalty Islands for the second (
The New Caledonian sandalwood is subject to exploitation through harvesting and is grown in plantations to satisfy the increasing international demand of sandalwood essential oil. However, its taxonomy appears to be in need of revision to more precisely describe the variability of this New Caledonian biodiversity hotspot species (
A first step of this revision is presented here, with the recognition of an endemic sandalwood variety from the Loyalty Islands based on morphological and molecular studies as well as examination of living plants and herbarium specimens.
The New Caledonian sandalwood,
In 1964, Hürlimann described a new variety based on a sample collected on the island of Maré in the Loyalty Islands (
In 1988, the revision of the New Caledonian
As the native Loyalty Islands sandalwoods are quite homogeneous, only one variety is to be recognized for the entire Loyalty archipelago, which is the one of Hürlimann. Thus, to reinstate the varietal name
New Caledonia, Loyalty Islands, Maré, près de Rawa, arbre, 8 m, en fleurs et en fruits, forêt mésophile, 17 July 1951,
Shrub to small tree 2–10 m tall, trunk up to 30 cm dbh; bark rough, grey to reddish-brown, longitudinally fissured; heartwood fragrant, yellowish to brownish.
Flowering and fruiting probably occurring throughout the year but with some peaks; herbarium samples provide the following data: flowers from December to August, fruits from January to August.
New Caledonia, endemic to Loyalty Islands; known only from Ouvéa, Lifou and Maré islands (Figure
Distribution map of New Caledonian varieties of
This variety is restricted to the calcareous soils of uplifted atolls between 5 and 80 m elevation and is closely linked with traditional agriculture which consists of shifting cultivation. Regeneration by seeds occurs mainly in the open cultivated areas and young fallow lands. Loyalty sandalwood is therefore characteristic of fallows, shrublands and secondary forests, and rarely occurs in mature forests. It is also commonly found along roads and close to villages in open areas where it is generally protected and managed by inhabitants. The surrounding vegetation is often composed of trees and shrubs, such as
Using the categories and criteria of IUCN Red List Category Vulnerable
The common names recorded for
The taxonomy of
Flowers of
Fruit of
(adapted from
1 | Inflorescence peduncles, rachis segments and outer surface of petals sparsely to densely hairy |
|
– | Inflorescence peduncles, rachis segments, outer surface of petals and petal internal margins glabrous |
|
2 | Leaf blade usually less than 3.5 × 1.5 cm; petiole less than 7 mm; blade adaxial surface glaucous and bluish in color; interstaminal disk lobes very narrow (W/L = 1/3–1/4) |
|
– | Leaf blade usually more than 3.5 × 1.5 cm; petiole more than 7 mm; blade adaxial surface not glaucous and bluish in color; interstaminal disk lobes wide (W/L = 1/2) |
|
3 | Seed usually more than 9 × 7.5 mm; globose (L/D < 1.2) |
|
– | Seed usually less than 9.5 × 7.5 mm; ovoid (L/D > 1.2) |
|
Essential oil of
To investigate the quality of Loyalty Islands sandalwood essential oil (
Loyalty Oil 1 (EI1) obtained in 2015 from Distillerie de Boulouparis (New Caledonia) with Ouvéa sandalwood,
Loyalty Oil 2 (EI2) obtained in 2002 from Michel Point and processed by Koop Cuada distillery with Maré and Lifou sandalwoods.
The gas-chromatography was performed on an apolar column (HP-1, 10 m x 0.1 mm, film 0.1m, 50° (1’) to 280° (2’) at 50°/min., vector gas: hydrogen). Its results are given in Table
The organoleptic evaluation showed that the Loyalty essential oil is lighter and less milky than the Indian sandalwood; the former has also a character less woody but more animal and masculine (P.-A. Blanc and S.A. Firmenich, pers. comm. 2015).
Main constituents of Loyalty Islands sandalwood (
Essential oil | (Z)-α-santalol (%) | (Z)-β-santalol (%) | (E)-lanceol (%) |
---|---|---|---|
ISO Standard 3518 : 2002 ( |
41 to 55 | 16 to 24 | - |
New Caledonia |
38.2 | 18.2 | 9.1 |
Loyalty Oil 1 | 44.3 | 19.4 | 14.1 |
Loyalty Oil 2 | 47.4 | 21.3 | 8.5 |
These findings are in accordance with
I am grateful to the Province des Iles Loyauté Herbier du Centre IRD de Nouméa
I thank Gildas Gâteblé (Institut Agronomique néo-Calédonien) for helpful discussions on Loyalty Islands
I am indebt to Christian Vial and Pierre-Alain Blanc (Firmenich S.A.) for, respectively, gas-chromatography analysis and organoleptic analysis of
Ouvéa. Lékine, 15 May 1976,
Lifou. July 1869,
Maré. Medu, dans les fourrés, 22 December 1925,
New Caledonia, Grande-Terre. Arama, collines près de la mer, 1855-60,
New Caledonia, Isle of Pines. 1852,