The shrinkspur is indigenous to the rainforest regions of Pandora. It grows exclusively away from the busy forest floor, typically sprouting horizontally from the trunks of tall trees.
The body of the shrinkpur is made of thick, tough fibre. Its flatly domed top and coned underside protect a soft and spongy core. It is named for the distinctive and wickedly sharp thorns which cover its body, and the plants' distinctive reaction to physical contact.
When the shrinkspur feels an animal stand on or brush against it, its sharp and abrasive thorns retract so that the plant can feed on any blood it has drawn. This passive hematophagy supplements the nutrients drawn via its roots with rich proteins and lipids.
Shrinkspurs always grow up high, usually sprouting from the trunks of tall trees. However, it has been noted to sometimes grow on rocky outcrops and cliff faces as well.
The strong body and root system of the shrinkspur can support the weight of an adult Na'vi. As a result, many Na'vi have learned the trick of triggering the shrinkspur's feeding retraction, using the plant to quickly help them scale trees when hunting or foraging.