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

Summary:
Features include 1) resupinate growth, mainly on hardwoods, 2) a cartilaginous-gelatinous fruitbody that is colorless or bluish gray and under a lens pruinose, sometimes with fertile strands extending over the surface or at the margins, 3) spores that are broadly elliptic to obovate, colorless, and with small blunt warts in Melzer''s reagent or cotton blue but nearly smooth in KOH, 4) basidia that are (2)4-spored, pleural (bifurcate at base), and cylindric to subclavate, 5) two types of cystidial elements: a) cystidia that are cylindric to slightly awl-shaped, thin-walled or basally thick-walled, the base often bifurcate, and b) smaller cystidioles that are few in number, cylindric or subclavate, and simple or capitate, and 6) a monomitic hyphal system, the hyphae with clamp connections, conglutinate or the walls becoming gelatinized. Although species names in Xenasma take the neuter ending, -cola refers to an inhabitant, and nouns do not agree with the gender of the genus.

Xenasma rimicola has been found in BC, WA, OR, ON, PQ, MI, and MO, (Ginns), as well as Finland and Norway, (Hjortstam), and Brazil, France, and New Zealand, (Liberta).

Fruiting body:
effused, thin, in section 0.002-0.005cm, closely adnate [firmly attached], consistency cartilaginous-gelatinous, drying to a semitransparent varnish-like film; when fresh colorless or bluish gray, sometimes yellowish in older parts, drying to whitish gray; under a lens pruinose; "sometimes with fertile strands extending over the surface or at the margins", (Liberta)

Microscopic:
SPORES (6.5)8.5-10.5 x (3.5)4.5-7 microns, broadly elliptic to obovate, slightly depressed on one side with a lateral apiculus, colorless, wall finely asperulate, the asperulations evident in Melzer''s reagent, disappearing in KOH, BASIDIA cylindric to subclavate, "borne directly on the horizontal hyphae, the base bifurcate, very often obscure", 15-24(29.5) x 7-8 microns, 2-4-spored, sterigmata 3-4.5 x 1.5 microns, arcuate; CYSTIDIAL ELEMENTS of 2 types: 1) cystidia 50-125 x 10-15 microns, cylindric to slightly subulate [awl-shaped], the base often bifurcate, wall thin in upper part, thickened in lower part, the thickened parts of the cystidia remaining as tubules in old specimens, 2) cystidioles 24-37 x 2.5-3.5 microns, cylindric or subclavate, simple or capitate, the bulb at the apex 3-5 microns wide; HYPHAE 1.5-2.5 microns wide, parallel to the substrate, nodose-septate [septa with clamp connections], conglutinate or the walls becoming gelatinized, (Liberta), SPORES (8)10-12 x 5-8 microns, broadly elliptic, nearly smooth in KOH, in Melzer''s reagent and in cotton blue with small blunt warts; BASIDIA 12-15(20) x 6-7 microns, subcylindric, pleural, generally with 4 sterigmata and a basal clamp connection; CYSTIDIAL ELEMENTS apparently of 2 types: 1) cystidia 70-130 microns long or in some cases even longer, tubular, "thin-walled or basally with slight wall thickening or distinctly thick-walled", 2) cystidioles few, about 20-35 microns long, subcapitate; HYPHAE monomitic, with clamp connections, (Hjortstam)