Overview
Sinclair’s Tooth Fungus (Phellodon sinclairii) is a distinctive, dark-hued hydnoid fungus endemic to the pristine temperate rainforests of New Zealand. Named in honor of 19th-century colonial surgeon and botanist Andrew Sinclair, this striking macrofungus flourishes along mossy forest floors, forming vital ectomycorrhizal symbioses with native southern beech trees. Rather than bearing traditional gills or pores, its undersurface is carpeted with thousands of delicate, downward-hanging spine-like teeth, making it a celebrated jewel of Antipodean mycological biodiversity.
Biology and Physical Characteristics
The morphology of Phellodon sinclairii is characterized by tough, fibrous, leathery caps that frequently fuse into irregular, overlapping rosettes. The upper pileus surface matures from velvety blue-gray or purplish-charcoal when young to a deep blue-black or brownish-slate when mature, often adorned with concentric zonation bands and pale margins. Instead of gills, the hymenophore consists of a dense bed of pale gray to lavender-tinted spines (teeth) measuring up to four millimeters in length. Each microscopic basidiospore is spherical and covered in tiny, prominent spines, discharged from the teeth into circulating ground breezes.
Behavior and Ecology
Phellodon sinclairii lives fundamentally as a perennial underground mycelial network interwoven with the root systems of native southern beech trees (Fuscospora and Lophozonia) and mānuka/kānuka shrubs. Through its extensive mycorrhizal mantle, the fungus extracts vital moisture and hard-to-reach minerals from nutrient-poor forest soils, transferring them to the host trees in exchange for carbon and sugars synthesized through forest canopy photosynthesis. Fruiting bodies emerge in late summer and autumn following heavy soaking rains, persisting on the forest floor for weeks due to their tough, leathery texture.
Conservation and Human Impact
Classified as Least Concern and considered Not Threatened under the New Zealand Threat Classification System, Sinclair’s tooth fungus remains widespread and common within intact native conservation estates. However, like all sensitive ectomycorrhizal fungi, it is vulnerable to the clear-felling of mature native forests, soil compaction by introduced feral ungulates (such as red deer and wild pigs), and atmospheric nitrogen deposition. The legal protection of expansive national parks across the South Island (such as Fiordland and Kahurangi) ensures the continued health of its native beech forest strongholds.
Interesting Factoid
Instead of having gills like typical mushrooms, Sinclair’s Tooth Fungus produces a carpet of thousands of tiny, pointed teeth hanging beneath its leathery blue-black cap.
Last updated: October 2026