Summary:
Features include 1) growth on wood, 2) an arid-waxy fruitbody, arising in small patches that become continuous; grayish white to ochraceous tawny; pruinose; and with margins somewhat lighter, abrupt at maturity, 3) suballantoid spores, 4) 2-4-spored basidia that are large and guttulate, 5) two types of dikaryophyses, and 6) a subiculum often containing calcareous concretions. This species as described in Wells(4) and Martin, G.W(1) is thought to be an unnamed species and not the same species as Exidiopsis calcea (Pers.) Wells (which is found in Eurasia and is very similar to or possibly identical to E. macrospora (Ell. & Everh.) Martin), (Wells(5)).

Microscopic:
SPORES 15-22 x (6)7.5-9.5 microns, cylindric-curved to suballantoid, granular to guttulate, germinating directly or by repetition; PROBASIDIA "at first elongate, becoming obovate to ovate", 2-4-spored at maturity, guttulate, 19-27(35) x (12)13-17.5 microns, "epibasidia tubular, up to 85 microns in length and 3-4 microns in width"; FERTILE HYPHAE tortuous, 2-4(5.5) in diameter, bearing basidia in clusters by proliferations through or near clamp connections at the base of the probasidia; DIKARYOPHYSES of 2 types: 1) cylindric to clavate, "arising from the fertile hyphae, frequently septate" with clamp connections, up to 50 microns in length and 2-7 microns wide, and 2) "simple to little branched, arising from the basal hyphal layer, tortuous, becoming indistinct", 0.5-2.5 microns wide, forming a layer 35-75 microns above the mature basidia; HYPHAE forming a thin basal layer and "an ascending layer terminating in the fertile hyphae and dikaryophyses"; basal hyphae 1.5-3 microns wide, parallel to the substrate in a thin layer, colorless, with clamp connections throughout, becoming indistinct; MINERAL ACCRETIONS often present in the subhymenium, numerous brownish mineral granules in the vicinity of the dikaryophyses and frequently attached to them, (Wells(4)), SPORES 15-22 x 7.5-9.5 microns, cylindric, unilaterally flattened or suballantoid; PROBASIDIA "at first oblong, finally ovate or obovate", mostly 19-24 x 13-16.5 microns, becoming cruciate-septate, epibasidia cylindric, 3-4 microns wide, up to 50 microns long; PARAPHYSES [dikaryophyses] of 2 types: 1) 2-3 microns wide, "clavate, clamp-bearing, often sparsely branched, arising as proliferations from the bases of the basidia", 2) 1-2 microns thick, tortuous, arising from the subiculum; hymenium consisting of sparsely scattered basidia borne terminally on short, erect, fertile hyphae 2-3 microns wide, the basidia proliferating from clamp connections at their bases, "and of paraphyses forming a layer 15-40 microns above the basidia"; subiculum varying from very thin to 100 microns thick, composed of agglutinated hyphae parallel with substrate, often containing 1 or 2 layers of calcareous concretions, (Martin)

Notes:
Exidiopsis ''calcea'' has been found in BC, WA, ID, AB, MB, NS, NT, ON, PE, SK, YT, AK, AZ, CA, FL, GA, IA, IL, LA, ME, MI, MN, MT, NC, NH, NY, and VT, (Ginns). It has been found in MB, SK, north central United States including IA, and IL, (Wells(4)), It occurs from ON, IL, IA, MB, ME to WA, south to FL, (Martin).