Tuber gibbosum is a species of truffle in the genus Tuber

Tuber

Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to survive the winter or dry months and provide energy and nutrients for regrowth during the next growing season and they are a means of asexual reproduction...

. It is found in the Pacific Northwest

Pacific Northwest

The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...

 region of the United States, where it grows in an ectomycorrhizal

Mycorrhiza

A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....

 association with Douglas-fir

Douglas-fir

Douglas-fir is one of the English common names for evergreen coniferous trees of the genus Pseudotsuga in the family Pinaceae. Other common names include Douglas tree, and Oregon pine. There are five species, two in western North America, one in Mexico, and two in eastern Asia...

.

Taxonomy and phylogeny

The species was first described by American mycologist Harvey Wilson Harkness in 1899. The specific epithet derives from the Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 word gibbosum meaning "humped", and refers to the irregular lobes and humps on larger specimens. T. gibbosum is part of the Gibbosum clade

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

of the genus Tuber. Species in this clade have unusual "peculiar wall thickenings on hyphal tips emerging from the peridial surface at maturity."