Summary:
{See also Earthstars Table.} Features include 1) small size, up to 3.7cm across when the outer covering of the fruitbody has expanded out into rays, 2) 4-5(8) star-like rays that are not hygroscopic, but raise the spore case as if on stilts still attached at their tips to a nest-like remnant in the ground formed from the outermost layer of the rays (i.e. fornicate), 3) hoary spore case on a short stalk, opening by a distinct cone-shaped peristome outlined by a distinct raised rim, 4) dark brown mature spore mass, and 5) round spores. Confusion has resulted because Geastrum coronatum (Schaeff.) J. Schroet. and Lycoperdon coronatum Scop. are said to be synonyms, but not Geastrum coronatum Pers. According to Bates(1), Geastrum coronatum in the sense of Lloyd(1902) and subsequent American authors and in the illustrations of G. coronatum (Schaeff.) J. Schroet. in Coker(3) is Geastrum quadrifidum as used by Pegler(4) and Bates(1). As an addendum for those particularly interested, what Smith(49) described as Geastrum coronatum Pers. (used here for a separate species) is probably also Geastrum quadrifidum Pers., and its description is included here. A.H. Smith says in Smith(4) in describing G. quadrifidum Pers. that it was generally known under the name G. coronatum in the older literature, and the Smith(4) description of G. quadrifidum Pers. corresponds more or less to the Smith(49) description as G. coronatum Pers. (see G. quadrifidum). Here is the summary of features of G. coronatum Pers. in Smith(49), corresponding instead to this species: "a very easy species to recognize because of the copious white mycelial coating of unopened fructifications, the peculiar sheen over the dark pedicellate spore sac with its basal collar, the fibrillose mouth delimited by a distinct pale circle, and the manner in which the fructification typically stands up on the points of the rays when fully expanded" (Smith(49)).

Microscopic:
spores 4.5-5.5 microns in diameter excluding ornamentation, (5)5.5-6.3 microns including ornamentation, round, verruculose, warts irregular, 0.3-0.5 microns high; capillitial hyphae 3-6 microns wide, "yellow-brown, thick-walled, with a narrow lumen", finely tapered to subacute tips 1 micron or less wide, "walls smooth or finely encrusted", (Pegler), spores 4.5-6 microns, round, verrucose [warty], about 12 warts round the circumference, brown, some with droplets; basidia not seen, cystidia not seen; capillitium threads up to 9 microns wide, thin-walled to thick-walled, red-brown, some finely incrusted, some septa with clamp connections; hyphae of the exoperidium and endoperidium thick-walled, without septa, colorless, (Breitenbach), spores 3.5-5 x 3.5-5 microns, round; capillitial threads very thick-walled, yellowish in KOH, (Smith(4)), spores 3.5-5 microns in diameter, round, covered with colorless truncate warts which more or less gelatinize in KOH, spores dark dull brown in KOH and near sepia in iodine; capillitial threads very thick-walled (lumen of cell visible as a line), yellowish in KOH, only slightly darker in iodine, (Smith(49))

Spore Deposit:
violet-brown (Breitenbach)

Notes:
Geastrum quadrifidum was found at least in Owyhee Co. in ID, (Ramsey), in the Great Lakes area of North America, and more widely distributed, (Smith(4)), known throughout the United States, and previously reported from AZ, CA, FL, MI, NJ, NY and TZ, also reported from Canada, Caribbean, Europe, United Kingdom, Japan, Mexico, New Zealand and South America, (Bates). The University of British Columbia has BC collections by Paul Kroeger and by Heather Stirling. Another collection from BC at the University of British Columbia was collected and determined by R. Bandoni under the name Geastrum minus - Geastrum minus was originally described as a variety of G. quadrifidum, but according to Bates(1) the name was used by Cunningham to include G. quadrifidum and G. minimum.

Synonyms and Alternate Names:
Fuscopostia lateritia "(Renvall) B.K. Cui, L.L. Shen & Y.C. Cui & Dai"
Oligoporus lateritius (Renvall) Ryvarden & Gilb. Syn. Fung.