Blue-foot conecap

Pholiotina cyanopus is a textbook 'little brown mushroom' (LBM) that carries a lethal payload.

Cap

The cap ranges from 1 to 3 cm across, starting sharply bell-shaped and opening to broadly convex with a low central boss (umbo).

It is hygrophanous - rich cinnamon or tawny brown when fresh and wet, fading to a dull buff-tan as it dries, often with a darker center.

Gills

The gills are pale buff when young and ripen to a definitive rusty cinnamon-brown, confirming the rusty spore print.

Spore print: rusty brown - take one on white paper before making any identification, as this single step distinguishes it from the lookalike Psilocybe whose print is dark purple-brown to near-black.

Stem

The most important identification feature is the persistent, membranous ring (annulus) on the upper part of the slender stem, whose upper face is often finely grooved and which becomes dusted rust-brown from shed spores - making it more visible.

The second key feature is the blue-gray to blue-violet coloration at the lower stem base (hence 'cyanopus' - blue-footed), which can range from subtle to quite noticeable. It is caused by pigments related structurally to psilocin but is NOT indicative of any psychoactive activity.

Do not mistake this blue coloring for the true bruising reaction of Psilocybe: it is a fixed pigment in the flesh, not a reaction to damage.

Amatoxin poisoning is a life-threatening medical emergency. Because of the 6-24 hour latent period before symptom onset, anyone who may have consumed this species - or any small brown ringed mushroom from a lawn or grassy area - must go to hospital immediately, even if they feel completely well.

Do NOT wait for symptoms. Bring any remaining specimens, a photograph, and if possible a vomit sample for identification.

Emergency management is supportive and specialized:

• aggressive IV hydration and electrolyte replacement
• activated charcoal (only if presentation is very early, within 1-2 hours)
• close monitoring of liver function, coagulation, and blood glucose
• silibinin (silymarin from milk thistle) if available
• repeated extracorporeal elimination (hemoperfusion) in severe cases
• liver transplantation evaluation for fulminant hepatic failure

The risk of fatal outcome rises sharply with delay in presentation. Inform the treating team that the species may contain amatoxins and that confusion with a psilocybin mushroom may have suppressed help-seeking.

The lethal agents are amatoxins - bicyclic octapeptide cyclopeptides, principally alpha-amanitin. These compounds irreversibly inhibit RNA polymerase II, the enzyme responsible for synthesizing messenger RNA in eukaryotic cells.

By shutting down mRNA production, amatoxins halt protein synthesis in cells throughout the body. The liver and kidneys - organs with the highest rates of protein turnover and metabolic activity - sustain the most severe damage.

The result is progressive hepatocellular necrosis and acute liver failure, frequently combined with renal tubular necrosis. The toxins are absorbed from the gut, excreted in bile, and undergo enterohepatic recirculation, prolonging exposure.

The blue pigment at the stem base (possibly a psilocin-related compound) is not psychoactive or directly toxic, but is responsible for the dangerous visual confusion with Psilocybe.

Amatoxin poisoning follows a deceptive three-phase clinical course that delays recognition and treatment.

1. 1Phase 1 - Latent period (6-24 hours after ingestion, sometimes up to 48 hours): the toxin is absorbed with no symptoms, and the victim feels well. This delay is the most dangerous aspect because the poisoning is not immediately recognized.
2. 2Phase 2 - Gastrointestinal phase (beginning 6-24 hours after ingestion): sudden onset of violent, cholera-like gastroenteritis - profuse watery diarrhoea, severe vomiting, abdominal cramps, and dehydration. Symptoms may ease after 24-48 hours, giving a false impression of recovery.
3. 3Phase 3 - Organ failure phase (days 3-6 and beyond): jaundice, elevated liver enzymes, coagulopathy, hypoglycemia, hepatic encephalopathy, and progressive hepatic and renal failure. Without aggressive medical intervention, this phase can be fatal.

If the victim consumed P. cyanopus believing it to be Psilocybe, early nausea may be misattributed to a 'bad trip' rather than poisoning, critically delaying emergency care.

TREAT AS LETHAL. Pholiotina cyanopus has been confirmed to contain amatoxins, the same class of cyclopeptide toxins responsible for the majority of fatal mushroom poisonings worldwide (predominantly from Amanita phalloides, Galerina marginata, and their relatives).

Even a single small fruitbody may contain a clinically significant dose of alpha-amanitin. Amatoxins are heat-stable, water-soluble, and resistant to drying and freezing - no method of cooking or preparation deactivates them.

The risk is compounded by the dangerous confusion with Psilocybe: a person who ingests P. cyanopus believing it to be a psychoactive mushroom may attribute early nausea to the expected effects of psilocybin and not seek help in the critical early window.

If any ingestion is suspected - even a taste - seek emergency medical care immediately and bring a specimen or photograph for identification. Do not wait for symptoms to develop.

This is a grassland and disturbed-ground decomposer that thrives in exactly the cultivated, managed environments where casual foragers are likely to encounter small brown mushrooms.

It appears in lawns, parks, golf courses, pasture margins, mossy roadside verges, and mulched garden beds, as well as at the grassy fringes of deciduous and mixed woodland. Rich organic soils, fertilized turf, and moist conditions all favor it.

Its occurrence in suburban and urban greenspace puts it in close proximity to people unfamiliar with LBM identification, including those who might naively assume any small lawn mushroom is either harmless or a psilocybin species.

The main fruiting period runs from late spring through early autumn in eastern North America, broadly May to October, with peak abundance from August through October.

Like many small grassland species, it materializes quickly - fruitbodies can appear within a day or two of warm, damp weather and are short-lived, withering and collapsing again almost as fast.

Because individual fruitings are so brief, a patch of lawn that looked bare yesterday may hold a flush today. In irrigated lawns or unusually wet summers, fruiting can begin earlier or extend later.

Pholiotina cyanopus is a saprotroph, quietly breaking down decaying grass roots, thatch, moss, humus, and buried organic matter - doing the same invisible recycling work in a managed lawn that its relatives do on the forest floor.

It fruits scattered to gregarious, sometimes in small loose clusters or arcs, pushing directly up through soil among grass or moss.

It forms no relationship with trees; it simply follows the organic richness of the soil, which is why fertilized turf and compost-rich garden beds suit it so well. Fruitbodies are fragile and decompose quickly once mature.

Flushes a few days after warm rainfall or irrigation once soil temperatures are in the 10-22 °C range; most productive in moist late-summer and early-autumn conditions.

Pholiotina cyanopus sits in a dangerous cluster of lookalikes that makes it exceptionally hazardous.

The most catastrophic confusion is with Psilocybe species (so-called 'magic mushrooms'), particularly P. semilanceata (Liberty Cap) and grass-inhabiting Psilocybe such as P. cubensis or P. cyanescens, sought for their psychoactive effects.

The blue coloration at the stem base of P. cyanopus is a visual trap - it resembles the blue bruising reaction of genuine Psilocybe, and inexperienced psilocybin seekers have mistaken P. cyanopus for psychoactive species with potentially fatal consequences.

Critical distinctions:

• Genuine Psilocybe bruise blue-green uniformly when the flesh is damaged anywhere (not just precolored at the base).
• Psilocybe have a dark purple-brown to near-black spore print, not rusty brown.
• Liberty Cap has a sharp nipple-like papilla and no persistent membranous ring.

A rusty-brown spore print immediately rules out psychoactive Psilocybe and confirms the deadly conecap.

Other lookalikes:

• The closely related Conocybe filaris (Fool's Conecap) is nearly indistinguishable in the field - also small, ringed, rusty-spored, and deadly - and the two may occur together.
• Galerina marginata (Funeral Bell), another lethal amatoxin-bearing LBM, typically grows on wood rather than open turf but shares the small stature, brown color, ring, and rusty spore print.
• Harmless Conocybe species (e.g., C. apala, Milky Conecap) lack the persistent membranous ring and are not ringed.
• Agrocybe species in lawns are generally larger and fleshier.

The key diagnostic combination for P. cyanopus is:

• rusty-brown spore print
• persistent membranous ring
• blue-gray stem base coloration
• grassy habitat