E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
{See also Earthstars Table.} The most important field characters are the asperulate surface of the spore sac and the sulcate [pleated] peristome, (Smith(49)). There are 6-12 rays which are hygroscopic.

A collection from BC was deposited at the University of British Columbia and determined by Paul Kroeger. It is widely distributed through northern temperate regions (Pegler(4)).

Outer Surface:
expanded fruitbody about 2-5cm across, the exoperidium splitting about halfway into 7-10 rays, "hygroscopic, rays spreading, usually arched when fresh and recurved at the tips, bending upwards onto the endoperidial body when dry"; outermost mycelial layer of rays persistent, binding debris; middle fibrous layer of rays whitish to pale gray-brown, not often exposed; innermost pseudoparenchymatous layer fleshy, at first pale brown, becoming darker when old, "eventually dark brown and often longitudinally wrinkled, persistent, usually not cracking or peeling", (Pegler), small, spherical, "submerged at first but becoming lifted up as it expands", 2.5-4cm across when expanded, "outer layer splitting past the middle or two-thirds of the distance to the base, becoming divided into 6 to 12 rays which usually have a layer of sand held to the under surface by a thin layer of mycelium, the rays expanded when wet and involute when dry, folding over or under the spore case in drying, fleshy layer chocolate color to umber, and soon wrinkled-rimose", (Smith(49))

Inner layer:
spore case 1.2-1.4cm across, more or less spherical or obovate; pale gray brown, usually densely covered in small warts that are often more prominent around the peristome [mouth], when old becoming worn and almost smooth; peristome conic, strongly plicate [pleated] with 15-20 grooves, "clearly delimited, usually with a slight, circular ridge", (Pegler), spore case pale gray-brown, "usually densely covered in small warts which are often more prominent around the peristome", when old becoming worn and almost smooth; peristome (mouth) conic, strongly plicate with 15-20 grooves, clearly delimited, usually with a slight, circular ridge spores case 0.8-1.5cm in diameter, nearly spherical, "color dingy but surface typically ashy gray from a coating of adnate asperulae causing the surface to feel rough; peristome prominent, conic, acute, seated on a more or less distinctly delimited zone, strongly sulcate and often dark-colored", (Smith(49))

Spore Mass:
dark brown; columella hemispheric to cylindric, pale brown, (Pegler), spore mass chocolate color (Smith(49))

Stem:
spore case on short stem, stem about 0.1-0.2cm long, "often flattened in cross-section", "whitish to brownish", (Pegler), sessile to short-pedicellate (Smith(49))

Microscopic:
spores (4.5)4.8-5.7 microns in diameter excluding ornamentation, 5.6-6.7 microns in diameter including ornamentation, "verruculae isolated, irregular in outline", 0.3-0.6 microns high, 0.3-1.2 microns wide, "This species seems to vary noticeably with regard to size and colour of the mature spores, and coarseness of the warts."; basidia not seen, capillitial hyphae pale yellow to almost colorless, "finely tapered, occasionally forked or lobed, thick-walled with a narrow lumen, smooth or partially encrusted", (Pegler), spores 6-7.5 microns in diameter, round, very dark brown in KOH, coarsely asperulate with colorless plugs "extending into a gelatinous matrix", "apedicellate or pedicel present only as a broken stump"; capillitial threads 3-5 microns wide, slightly flexuous, pale yellowish in KOH, walls thickened, no cross walls seen, rarely branched, (Smith(49))