Cortinarius globuliformis

Cap

Cap 4-9 cm across, starting convex and broadening to umbonate or nearly flat with age.

When the air is damp the cap surface is smooth and lightly sticky - a viscid sheen of pale ochre-buff to violet-buff or pale lilac-brown, usually darkest at the centre.

In dry weather the stickiness fades and the colour settles to a flat, dull ochre-tan; moist conditions reveal the true character of the cap surface.

Gills

The gills are adnate to sinuate and moderately crowded. They open pale violet-grey and slowly shift toward rust-brown as the spores ripen - a quiet progression that acts as an age marker you can read at a glance.

Gill edges remain paler and finely fringed throughout.

Stem

The stem stands 5-10 cm tall and 1.5-3 cm thick, but its most memorable feature is the pronounced near-spherical bulb at the base - round enough that it gave the species its name, globuliformis.

This bulb may be partially buried in litter, so it is worth easing the stem out of the ground carefully to see it fully. The stem surface is fibrillose and whitish to pale violet-buff.

In young, freshly emerged specimens the cortina is one of the most distinctive things to look for: a fine cobweb of pale whitish to lilac threads spanning from the cap margin down to the upper stem, like a delicate curtain drawn over the gills.

As the cap expands the cortina tears and collapses, leaving behind only a rust-brown ring-zone of settled spores on the stem as a clue to what was there.

Spore print

Spore print rust-brown to ochre-brown - always take a print when assessing any cortinarioid mushroom.

The extreme latency of orellanine poisoning places it among the most insidious mushroom toxin syndromes. Unlike amatoxins, where symptoms begin within 6-24 hours, orellanine victims may feel entirely normal for up to three weeks - by which time irreversible nephrotoxic damage may be far advanced.

Studies on orellanine poisoning outbreaks in Europe (primarily from Cortinarius orellanus and C. rubellus) document that a significant proportion of victims require long-term dialysis, and some require kidney transplantation. Australian Cortinarius species must be treated as equivalent risks.

The absence of established common names for species like C. globuliformis, combined with the visual similarity of many webcap species, makes the risk of misidentification by inexperienced collectors significant.

All brown, buff, or violet-toned gilled mushrooms with rust-brown spore prints and cortina remnants on the stem found in native Australian forest should be treated as carrying lethal potential.

Orellanine (3,3′,4,4′-tetrahydroxy-2,2′-bipyridine-1,1′-dioxide) and related compounds, including orelline, are bipyridine N-oxide nephrotoxins. They target the proximal tubule cells of the kidney, generating reactive oxygen species and disrupting cellular metabolism.

Multiple Australian Cortinarius species have been confirmed to contain orellanine by chemical analysis. C. globuliformis, as part of this native complex, carries the same presumed risk.

The toxin is chemically stable across a wide range of temperatures and pH levels.

Orellanine poisoning follows a characteristically deceptive course. After ingestion there may be no symptoms at all, or only mild nausea, for 2 days to 3 weeks - a latent period far longer than any other class of mushroom toxin.

When symptoms eventually manifest they include:

• Intense thirst
• Frequent urination (polyuria), followed later by reduced output
• Headache
• Nausea
• Vomiting
• Fatigue
• Chills
• A burning sensation in the mouth or throat

These progress to oliguria (reduced urination), flank pain, and frank acute kidney injury as tubular necrosis advances.

In severe cases, oliguric renal failure requires dialysis and some patients progress to permanent renal failure requiring kidney transplantation. The long delay between ingestion and symptom onset means patients frequently cannot recall the causative meal by the time they present to hospital.

Never consume any Cortinarius species collected from Australian native forest. The genus contains orellanine and related orellanin compounds, which are irreversible nephrotoxins.

The critical danger lies in the exceptional latency period: poisoning symptoms may not appear for 2 days to 3 weeks after ingestion, creating a deceptively reassuring window during which kidney damage accumulates silently.

By the time symptoms present - thirst, reduced urine output, nausea, and eventually kidney failure - substantial irreversible damage has often already occurred. There is no antidote.

If any Cortinarius consumption is suspected, seek emergency medical care immediately regardless of whether the person feels well. In Australia, call the Poisons Information Centre on 13 11 26.

C. globuliformis belongs to the forest - it cannot survive without a living tree host, threading its mycelium through roots in a mycorrhizal partnership that may run for years through the same patch of soil.

It favours moist sclerophyll forests and montane woodlands of southeastern Australia, most reliably found under Eucalyptus or among Nothofagus in shadier, moisture-retaining sites: gully floors, stream edges, sheltered slopes where leaf litter stays cool and damp.

It occurs singly or in small scattered groups, not dense clusters. The known distribution centres on Victoria, New South Wales, Tasmania, and the ACT.

Potential occurrence in comparable South Island Nothofagus forest in New Zealand has been noted, though those records await confirmation.

Fruiting runs from autumn into early winter in the Southern Hemisphere - roughly March through June - peaking in April and May. This is when falling soil temperatures and the first significant autumn rains break the dry-season dormancy and trigger flushing.

Spring and summer are quiet; the mycelium works unseen underground until the conditions are right. In warm or dry autumns, fruiting may be sparse or slow to begin.

C. globuliformis is an obligate ectomycorrhizal fungus - it lives only in partnership with its host tree roots and cannot be cultivated alone.

What you see above the litter is just the tip of a long-running relationship: the mycelium may have been trading minerals for sugars with the same tree for years before a single fruiting body breaks the surface.

Fruiting bodies emerge singly or in loosely scattered groups, never in tight tufts or dense clusters. The globose basal bulb is often partly buried in leaf litter; easing the whole stem out carefully is the only reliable way to observe it.

Fruits after autumn rain events as soil temperatures fall below 15 °C; standard ectomycorrhizal autumn-flush pattern consistent with SE Australian Cortinarius ecology.

Cortinarius globuliformis belongs to the Phlegmacium subgroup within Cortinarius, a large and taxonomically complex assemblage of viscid-capped webcaps. In Australia this group includes many morphologically similar species that share the viscid cap, rust-brown spore print, and ectomycorrhizal forest habitat.

Distinguishing C. globuliformis from close relatives relies heavily on the unusually globose basal bulb and the pale violet-buff colouration, but these features overlap with other species, and species-level determination within this group is a specialist task requiring microscopy.

Globally similar Phlegmacium species include European webcaps such as Cortinarius largus and C. glaucopus.

Outside the Cortinarius genus, collectors unfamiliar with Australian fungi occasionally confuse buff-capped, gilled forest mushrooms with edible species like field mushrooms (Agaricus) or Laccaria species, but the rust-brown spore print and cobweb cortina remnants firmly identify the genus as Cortinarius.