Overview
The Black Tooth (Phellodon niger), also known as the black tooth fungus or fragrant hydnum, is an enigmatic and visually striking tooth fungus native to old-growth boreal and temperate conifer forests of the Northern Hemisphere. Belonging to the family Bankeraceae, this tough, corky basidiomycete lacks conventional gills, producing instead hundreds of delicate downward-hanging spines beneath its cap. Famous for its intense blue-black interior flesh and pleasant, fenugreek-like herbal aroma when dried, Phellodon niger is a vital ectomycorrhizal partner that anchors ancient pine forest ecosystems.
Biology and Physical Characteristics
Phellodon niger produces a flattened to funnel-shaped cap that often fuses with neighboring caps into irregular, undulating rosettes. The upper surface is velvety when young, displaying concentric zones of ash-gray, midnight-blue, and charcoal-black, bordered by a pale white or cream growing margin. Underneath the cap, the hymenium consists of crowded, slender, downward-pointing spine-like teeth that mature from pale gray to deep purplish-black. When sliced open, the tough, fibrous flesh reveals a striking, deep blue-black coloration. It produces white, echinulate (spiky) basidiospores that drop from the teeth into circulating forest air currents.
Behavior and Ecology
The ecological life of Phellodon niger centers on an obligate mutualism with conifers, particularly Scots pine (Pinus sylvestris) and Norway spruce (Picea abies). Its underground mycelium envelops the host tree’s roots in nutrient-poor sandy soils, mobilizing tightly bound phosphorus and water for the tree in exchange for photosynthetic carbohydrates. Fruiting bodies emerge in late summer and autumn, often persisting for months due to their tough, leathery texture. When the mushroom dries, it emits a distinct, sweet curry- or fenugreek-like fragrance caused by lactone compounds.
Conservation and Human Impact
Globally evaluated as Least Concern, Phellodon niger is nevertheless highly sensitive to environmental disturbance and is red-listed as Endangered or Vulnerable in several western European countries (such as the UK, Netherlands, and Germany). The primary threat is atmospheric nitrogen deposition from agricultural runoff and vehicular emissions, which enriches forest soils and disrupts delicate ectomycorrhizal fungal networks. Preserving unfertilized old-growth pine woodlands with intact moss floors is crucial for its continued survival.
Interesting Factoid
When sliced open, the Black Tooth fungus reveals surprising deep blue-black flesh like midnight velvet, and when dried, it smells deliciously like sweet curry and fenugreek!
Last updated: October 2026