Parasitaxus usta is a rare
speciesIn biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of conifer of the
familyIn biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
PodocarpaceaePodocarpaceae is a large family of mainly Southern Hemisphere conifers, comprising about 156 species of evergreen trees and shrubs. It contains 19 genera if Phyllocladus is included and if Manoao and Sundacarpus are recognized....
, and the sole species of the
genusIn biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Parasitaxus. It is a woody
shrubA shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
up to 1.8 m found only in the remote, densely forested areas of
New CaledoniaNew Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
, first discovered and described by Vieillard in 1861.
It is generally mentioned that
Parasitaxus usta is the only known parasitic
gymnospermThe gymnosperms are a group of seed-bearing plants that includes conifers, cycads, Ginkgo, and Gnetales. The term "gymnosperm" comes from the Greek word gymnospermos , meaning "naked seeds", after the unenclosed condition of their seeds...
. The species remarkably lacks
rootIn vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s and is always found attached to the roots of
Falcatifolium taxoidesFalcatifolium taxoides is a species of conifer in the Podocarpaceae family. It is found only in New Caledonia.-References:* Conifer Specialist Group 1998. . Downloaded on 10 July 2007....
(another member of the Podocarpaceae). However, the question is still left open, as the plant is in any case not a
haustorialIn botany, a haustorium is the appendage or portion of a parasitic fungus or of the root of a parasitic plant that penetrates the host's tissue and draws nutrients from it. Haustoria do not penetrate the host's cell membranes.Fungi in all major divisions form haustoria...
parasite, which is usually the case with angiosperms. Certain experts therefore consider the plant as a
myco-heterotrophMyco-heterotrophy is a symbiotic relationship between certain kinds of plants and fungi, in which the plant gets all or part of its food from parasitism upon fungi rather than from photosynthesis. A myco-heterotroph is the parasitic plant partner in this relationship...
.
Recent studies suggest a close relationship between this species and the genus
LepidothamnusLepidothamnus is a genus of conifers belonging to the podocarp family Podocarpaceae. The genus includes three species of dioecious evergreen trees and shrubs, and creepers. L. intermedius and L. laxifolius are native to New Zealand. L...
, especially with
Lepidothamnus fonkiiLepidothamnus fonkii is a species of conifer in the Podocarpaceae family.It is found in Argentina and Chile.It is threatened by habitat loss.-Source:* Conifer Specialist Group 1998. . Downloaded on 10 July 2007....
.
The species was first described as
Dacrydium ustum Vieill.; other synonyms include
Podocarpus ustus (Vieill.) Brogn. &
GrisJean Antoine Arthur Gris was a French botanist who was a native of Châtillon-sur-Seine, in the department of Côte-d'Or....
, and
Nageia usta (Vieill.)
KuntzeOtto Carl Ernst Kuntze was a German botanist.-Biography:Otto Kuntze was born in Leipzig.An apothecary in his early career, he published an essay entitled Pocket Fauna of Leipzig. Between 1863 and...
. 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). The scientific name translates as "Burnt Parasitic Yew."