Geastrum schmidelii  

A small (1-3 cm), pale brown earthstar with 5-8 rays, often encrusted in sandy debris, growing amongst grass and moss in dune slacks and occasionally other calcareous, sandy sites. Fruitbodies have a conical, plicate (folded/ridged) beak of the peristome (apical opening), and a small stalk beneath the endoperidial body (the "spore sack"), which help differentiate from other lookalikes in these habitats.

Fruitbody hypogeous (under or level with the ground) at first, subglobose to depressed or ovate, rarely umbonate (round), strongly encrusted withsand and debris. Expanded fruitbody 14-37 mm across, rarely larger, splitting to about half way into 5-8 rays, rays non-hygroscopic (absorbing moisture from the air), arched and somewhat recurved or almost horizontal. Mycelial layer present, persistent, strongly encrusting sand and debris. Fibrous layer papery, whitish to pale yellowish brown. Pseudoparenchymatous layer whitish at first, becoming pale brown, darkening with age and usually dark brown in dried specimens. Endoperidial body short-stalked, subglobose to ovate or depressed, 5-12 mm diam., with an apophysis (a swelling on the underside of the spore sac); stalk 1-2 mm high (dried), whitish. Endoperidium grey-brown to clay-coloured, often minutely whitish-pruinose (covered with white powdery granules) when fresh, becoming smooth. Peristome usually distinctly delimited by a low, circular ridge and paler than the surrounding endoperidium, usually acutely conical, 2-4 mm high, plicate (folded), mostly with 14-20 ridges. Columella (a column-like clump of sterile tissue to be found inside the inner peridium) small and rather weakly developed, rounded to narrowly clavate (club-shaped). Mature gleba dark brown. Basidia not seen. Capillitial hyphae 2-6 µm diam., pale brown to yellow-brown or almost hyaline (translucent), thick-walled with a narrow, discontinuous lumen, gradually and finely tapered to rounded or subacute tips 1-2.5 µm diam., irregularly encrusted. Spores dark brown, globose, verruculose (with moderately sized growths), 4.8-5.6 µm diam. excluding ornament, 5.6-6.5 µm diam. including ornament, verruculae irregular, often coalescent, 0.3-0.7 µm high, 0.3-1.5 µm across.

Adapted from Pegler, Spooner, and Laessoe (1995). “British puffballs, earthstars and stinkhorns: an account of the British gasteroid fungi.” Royal Botanic Gardens, Kew.