Abstract A description is provided for Acarospora sinopica , a lichen-forming fungus occurring on rocks, particularly iron-rich rocks and mine-spoil heaps, often in exposed situations, and particularly in mountainous areas. Some information on its associated organisms and substrata, dispersal and transmission, habitats and conservation status is given, along with details of its geographical distribution (Africa (Algeria, Morocco, South Africa, Tunisia)), Antarctica (Antarctica), Arctic Ocean (Greenland, Norway (Svalbard and Jan Mayen)), Asia (Afghanistan, China (Yunnan), Georgia, Iran, Russia (Altai Krai, Altai Republic, Irkutsk Oblast, Kamchatka Krai, Magadan Oblast, Republic of Buryatia, Republic of Khakassia), Turkey), Australasia (Australia (New South Wales, South Australia, Tasmania, Victoria, Western Australia), New Zealand), Europe (Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Isle of Man, Italy, Latvia, Netherlands, Norway, Poland, Portugal, Romania, Russia (Arkhangelsk Oblast, Komi Republic, Leningrad Oblast, Murmansk Oblast, Republic of Dagestan, Republic of Karelia, Republic of North Ossetia-Alania), Slovakia, Spain, Sweden, Switzerland, UK), North America (Canada (British Columbia, Newfoundland and Labrador, Nova Scotia, Nunavut, Ontario, Quebec), USA (California, Colorado, Idaho, Maine, Massachusetts, New Hampshire, New York, North Carolina, Tennessee, Vermont, Washington)). Acarospora sinopica has a remarkable ability to accumulate heavy metals, with levels of up to 60,000 ppm in dry weight being recorded.