red-cage fungus

Before the volva opens, the fruiting body is egg-shaped to roughly spherical, up to 6 cm (2+1⁄4 in) in diameter, with a gelatinous interior up to 3 mm (1⁄8 in) thick. White to grayish in color, it is initially smooth, but develops a network of polygonal marks on the surface prior to opening as the internal structures expand and stretch the peridium taut. The fruit body, or receptacle, bursts the egg open as it expands (a process that can take as little as a few hours), and leaves the remains of the peridium as a cup or volva surrounding the base. The receptacle ranges in color from red to pale orange, and it is often lighter in color approaching the base. The color appears to be dependent upon the temperature and humidity of the environment. The receptacle consists of a spongy network of "arms" interlaced to make meshes of unequal size. At the top of the receptacle, the arms are up to 1.5 cm (1⁄2 in) thick, but they taper down to smaller widths near the base. A cross-section of the arm reveals it to be spongy, and made up of one wide inner tube and two indistinct rows of tubes towards the outside. The outer surface of the receptacle is ribbed or wrinkled. There are 7–20 angular windows and 80–120 mesh holes in the receptacle. A considerable variation in height has been reported for the receptacle, ranging from 5 to 20 cm (2 to 8 in) tall. …

Like most of the species of the order Phallales, Clathrus ruber is saprobic—a decomposer of wood and plant matter—and is commonly found fruiting in mulch beds. The fungus grows alone or clustered together near woody debris, in lawns, gardens, and cultivated soil. Clathrus ruber was originally described by Micheli from Italy. It is considered native to southern and central continental Europe, as well as Macaronesia (the Azores and the Canary Islands), western Turkey, North Africa (Algeria), and western Asia (Iran). The fungus is rare in central Europe, and is listed in the Red data book of Ukraine. The fungus has probably been introduced elsewhere, often because of the use of imported mulch used in gardening and landscaping. It may have extended its range northwards into the British Isles or been introduced in the nineteenth century. It now has a mainly southerly distribution in England and has been recorded from Cornwall, Devon, Dorset, Somerset, the Isle of Wight, Hampshire, Berkshire, Sussex, Surrey, and Middlesex. In Scotland, it has been recorded from Argyll. It is also known from Wales, the Channel Islands, and Ireland. The fungus also occurs in the United States in urban areas of its likely introduction (in California, Florida, Georgia, Hawaii, Alabama, Virginia, North Carolina, and New York), as well as in Canada, Mexico, and Australasia. …

The generic name Clathrus is derived from Ancient Greek κλειθρον or "lattice", and the specific epithet is Latin ruber, meaning "red". The mushroom is commonly known as the "basket stinkhorn", the "lattice stinkhorn", or the "red cage". It was known to the locals of the Adriatic hinterland in the former Yugoslavia as veštičije srce or vještičino srce, meaning "witch's heart". This is still the case in parts of rural France, where it is known as cœur de sorcière.