The cap is the colour of orange peel. Bright. Wet. The surface is greasy to the touch. Not sticky. Greasy. Like wax. The genus name means water head. The cap is convex at first. It flattens with age. The margin becomes scalloped. Wavy. The gills are thick. Waxy. Pale orange. They run down the stem. The stem is the same colour as the cap. Paler at the base. It is hollow. Brittle. It breaks cleanly. Pull a mushroom from the ground. The stem snaps. The cap remains. The gills shine in the rain. The Wetland Waxcap is beautiful. It is also rare. Beauty does not protect it. Diet is saprotrophic but specialised. Hygrocybe irrigata decomposes organic matter in wetland soils. Moss litter. Sedge roots. The accumulated thatch of damp grasslands. The fungus does not consume wood. It does not consume dung. It lives in the top few centimetres of soil. The mycelium spreads through the root zone. It fruits in autumn. March to May. The mushrooms appear after rain. They persist for days. They dry in the sun. They rehydrate in the next shower. The waxy surface prevents waterlogging. The cap stays greasy. The gills stay spaced. The spores form. The cycle repeats. The fungus needs undisturbed soil. Ploughing kills it. Drainage kills it. Fertiliser kills it. Habitat is restricted to natural wetlands that have not been drained. Sedge-dominated fens. The margins of shallow tarns. Damp depressions in pasture that have never been ploughed. The fungus requires a specific water regime. Flooded in winter. Damp in spring. Dry enough in summer to prevent waterlogging. The water table must fluctuate. The fungus has adapted to the fluctuation. It fruits when the water table drops. When the soil is damp but not saturated. Too wet and the mycelium drowns. Too dry and it desiccates. The window is narrow. The fungus times its fruiting to the autumn drawdown. The timing is precise. The margin for error is small. Threats are severe and cumulative. Wetland drainage for agriculture has removed ninety percent of New Zealand's natural wetlands. The Wetland Waxcap has lost ninety percent of its habitat. The remaining wetlands are fragmented. Small. Isolated. Each fragment hosts a small population. Small populations are vulnerable to extinction. A single drought. A single summer fire. A single incursion of an introduced plant. The population disappears. The next closest population is kilometres away. Spores do not travel that far. The gap is permanent. The fungus does not return. The second threat is nutrient enrichment. Runoff from farms adds nitrogen and phosphorus. The waxcap evolved in low-nutrient soils. Enrichment changes the microbial community. The waxcap loses. Weeds win. The wetland changes. The fungus is left behind. Range across New Zealand is now fragmented and coastal. North Island populations persist in Northland, Waikato, the Hauraki Plains, the Manawatu, and Wairarapa. South Island populations occur in Nelson, Marlborough Sounds, West Coast, Canterbury, Otago, and Southland. Also present on Stewart Island and the Chatham Islands. The species was once widespread. Now it is local. Each remaining population is small. Each is vulnerable. The fungus continues to fruit in autumn. The mushrooms appear. Bright. Orange. Waxy. They are a signal. The signal says the wetland is still intact. When the mushrooms stop appearing, the signal stops. No one notices. The wetland dries. The houses spread. The fungus is forgotten.