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Calostoma cinnabarinum is a species of gasteroid fungus in the family Sclerodermataceae, and is the type species of the genus Calostoma. It is known by several common names, including stalked puffball-in-aspic and gelatinous stalked-puffball. The fruit body has a distinctive color and overall appearance, featuring a layer of yellowish jelly surrounding a bright red, spherical head approximately 2 centimeters (0.8 in) in diameter atop a red or yellowish brown spongy stipe 1.5 to 4 cm (0.6 to 2 in) tall. The spore surface features a pattern of small pits, producing a net-like appearance. A widely distributed species, it grows naturally in eastern North America, Central America, northeastern South America, and East Asia. C. cinnabarinum grows on the ground in deciduous forests, where it forms mycorrhizal associations with oaks.