Parasitaxus

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Parasitaxus usta
Conservation status
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Podocarpaceae
Genus: Parasitaxus
de Laub.
Species: P. usta
Binomial name
Parasitaxus usta
(Vieill.) de Laub.

Parasitaxus usta (Corail) is a rare species of conifer of the family Podocarpaceae, and the sole species of the genus Parasitaxus. It is a woody shrub up to 1.8 m found only in the remote, densely forested areas of New Caledonia, first discovered and described by Vieillard in 1861.

It is generally mentioned that Parasitaxus usta is the only known parasitic gymnosperm. The species remarkably lacks roots and is always found attached to the roots of Falcatifolium taxoides (another member of the Podocarpaceae). However, the question is still left open, as the plant is in any case not a haustorial parasite, which is usually the case with angiosperms. Certain experts therefore consider the plant as a myco-heterotroph.

Recent studies suggest a close relationship between this species and the genus Lepidothamnus, especially with Lepidothamnus fonkii.

The species was first described as Dacrydium ustum Vieill.; other synonyms include Podocarpus ustus (Vieill.) Brogn. & Gris, and Nageia usta (Vieill.) Kuntze. The name is often cited as Parasitaxus ustus, but this is grammatically incorrect, as the genus name Parasitaxus is (like Taxus) feminine, with which the species name must agree (Nickrent 2006).

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