Starfish four-bladed (Geastrum quadrifidum) photo and description

Starworm four-bladed (Geastrum quadrifidum)

  • Department: Basidiomycota (Basidiomycetes)
  • Subdivision: Agaricomycotina (Agaricomycetes)
  • Class: Agaricomycetes (Agaricomycetes)
  • Subclass: Phallomycetidae (Veselkovye)
  • Order: Geastrales
  • Family: Geastraceae (Geastric or Starfish)
  • Genus: Geastrum (Geastrum or Zvezdovik)
  • Species: Geastrum quadrifidum (Starfish four-bladed)
    Other names for the mushroom:
  • Star wheel four-part
  • Geastrum four-bladed


  • Star wheel four-part
  • Geastrum four-bladed
  • Earth star four-bladed

Starworm four-bladed (Geastrum quadrifidum)


Fruiting bodies are initially closed, spherical, about 2 cm in diameter, covered with peridium, along the entire surface of which mycelial strands are located; mature - open, 3-5 cm in diameter. Peridium is four-layered, consists of exoperidium and endoperidium. Exoperidium in the form of a bowl, three-layer or two-layer, hard, torn from top to bottom to the middle into 4 unequal, pointed parts (lobes), bending down, and the fruiting bodies rise up on the lobes, as on "legs". The outer mycelial layer is whitish, felt, covered with soil particles, and soon disappears. The middle fibrous layer is white or isabella, smooth. The inner fleshy layer is white, also torn into 4 parts, with sharp ends resting on the sharp ends of the blades of the outer layer, soon disappears. The base is convex.The middle rises up together with the inner part of the fruiting body - gleba. A spherical or oval (ovoid) gleb is covered with endoperidium, 0.9-1.3 cm high and 0.7-1.2 cm wide. At the base with a flattened leg, above which the endoperidium is narrowed and a well-visible rounded protrusion (apophysis) is formed, at the apex it opens with an opening, which is equipped with a low peristome. The peristome is conical, fibrous, with a sharply circumscribed courtyard, smoothly fibrous-ciliated, around which there is a clear ring. The stem is cylindrical or slightly flattened, 1.5-2 mm high and 3 mm thick, whitish. The column is cotton-wool, light brown-gray in section, 4-6 mm long. Its exoperidium ruptures more often by 4, less often by 4-8 unequal pointed lobes, bending downward, which is why the entire fruiting body rises up on the lobes, as on legs.

The leg (in the traditional sense) is missing.

Gleba is powdery when ripe, black-purple to brown. The spores are brownish, light or dark brown.

When pressed, spores fly in all directions. Spores are olive brown.


The four-bladed starfish grows mostly on sandy soil in deciduous, mixed and coniferous - pine, spruce, pine-spruce and spruce-deciduous forests (among the fallen needles), sometimes in abandoned anthills - from August to October, rarely. Recorded in Russia (European part, Caucasus and Eastern Siberia), Europe and North America. We found it southeast of St. Petersburg in a mixed forest (birch and spruce) under an old spruce on needles in early October (the mushrooms grew as a family).


The four-bladed starfish is very peculiar in appearance and is strikingly different from mushrooms of other genera and families. It is similar to other starfish, for example, the Arched starfish (Geastrum fornicatum), whose exoperidium splits into two layers: the outer one with 4-5 short, blunt lobes and the inner, convex in the center, also with 4-5 lobes; on Zvezdovik crowned (Geastrum coronatum) with leathery, smooth exoperidium, splitting into 7-10 gray-brown pointed lobes; on Fringed starfish (Geastrum fimbriatum) with exoperidium, which is torn by half or 2/3 - by 5-10 (less often up to 15) unequal blades; on Zvezdovik striped (G. striatum) with exoperidium, bursting into 6-9 lobes, and light gray gleb; on small Shmiela Starfish (G. schmidelii) with exoperidium, forming 5-8 lobes,and a gleba with a beak-shaped grooved striped nose; on Zvezdovik triple (Geastrum triplex) with a fibrous hole at the top of a gray-brown block.

It is confined to the soils of deciduous and coniferous forests.