Xylosma mandjeliana (syn. Lasiochlamys mandjeliana) is a species of flowering plant in the family Salicaceae, endemic to New Caledonia. Formerly a member of Lasiochlamys, the new name was given in 2023 when the genus was transferred to Xylosma. It is listed as a protected species by the and was classified as vulnerable by the IUCN Red List in 1998.
Xylosma mandjeliana is a shrub or tree reaching up to a reported in height, characterized by a bushy or slender habit with branches that are at the tips, featuring thin reddish-brown bark that is both densely and lenticellate. The leaves measure up to long and wide, are glabrous, slightly revolute, glossy dark green above, light green below, and often tinged with red; the shape is oblong or obovate, the apex is rounded or emarginate, the base is cuneate, and the margins are entire. The leaf surface is , and the veins come in pairs that form a pattern; the petiole is short, measuring up to long.
The flowers are reportedly whitish, yellow, greenish-white, or reddish, growing in fascicles or short racemes, typically connected by an pedicel. The tepals are oblong or obovate, measuring long; the outer tepals are outwards and inwards, while the inner tepals are similar but smaller in size; both sets display ciliolate margins. Female flowers bear an ovary featuring an apex that is tipped by subsessile stigmas. The fruit is , usually green, and measures roughly in diameter.
The range of Xylosma mandjeliana is restricted to New Caledonia, and is only documented from a limited extent in northern Grande Terre, occupying the communes of Ouégoa and Pouébo. Notable localities where it is present include the Diahot River, the forest of Tendé, and Mont Mandjélia of both the Ouégoa and Pouébo communes; and Mont Colnett of the southern Pouébo commune.
Xylosma mandjeliana is a tropical species reported from a narrow range of habitats at elevations of up to . Being found in montane and riparian environments, it occurs in flat or sloped forests and along ridges. Additionally, it is noted to be in humid forest on mica schists.
Xylosma mandjeliana was first described in 1974 by Hermann Otto Sleumer under the name Lasiochlamys mandjeliana, in the family Flacourtiaceae. This system was brief however, as Sleumer would hastily refute the accuracy of the family in 1975. As a result, Lasiochlamys mandjeliana, along with its genus, were changed to be in Salicaceae.
An ecological study in 1980 by Tanguy Jaffré noted that Lasiochlamys could be differentiated from Xylosma for lacking the property of accumulating nickel, but this would later prove ineffective as a distinguishing trait. In 2005, Mac Haverson Alford published a thesis in which Lasiochlamys was suggested to be nested in Xylosma based on molecular phylogenetic analysis. It was not until 2023 however, when Lasiochlamys was ultimately synonymized with Xylosma by Yohan Pillon, resulting in the transfer of all of its species to the new classification. This revision resulted in the renaming of Lasiochlamys mandjeliana to its now recognized name; Xylosma mandjeliana. Decades earlier, Xylosma underwent a gender agreement whose purpose was to match the specific epithets with the female generic name; it was likely initiated by William T. Stearn in 1992 when he commented on the gender inaccuracy, and finalized by Dan Henry Nicolson in 1994. Despite this, Xylosma mandjeliana was not subject to it because the taxon was published after the agreement took place.
The generic name Xylosma derives from (), meaning "wood" or "tree", and (), meaning "smell", overall referring to the aromatic wood found in some species. The specific epithet, mandjeliana, is in reference to Mont Mandjélia, which is where the type specimen was obtained. As for the defunct genus Lasiochlamys, it stems from (), meaning "hairy," and (), meaning "cloak".
Xylosma mandjeliana was classified as vulnerable by the IUCN Red List under its old name in 1998; the assessment itself has many missing elements and needs updating due to its age. It is listed as a protected species by the National Natural Heritage Inventory also under its previous name, though further information on its status is absent.