|Major Groups > Gilled Mushrooms > Pink-Spored > Entolomatoid Mushrooms > Entoloma alboumbonatum|
by Michael Kuo
This striking entolomatoid mushroom has a conic, white cap with a silky appearance and a protruding central "nipple." It looks a bit like a white version of Entoloma murrayi, which is yellow, or Entoloma quadratum, which is orange—and, like those species, it features cuboid spores that are 4-sided in profile view and look like little ice cubes. The stem of Entoloma alboumbonatum is also white, and remains so through development. The gills are initially white, but with maturity they develop the pink tones characteristic of entolomatoid gills and spore prints.
Entoloma alboumbonatum is the same as Entoloma conicum, according to Baroni (2017) and Largent (1994). I have not studied the type collections, but the two collections I have studied manifest enough differences that they should probably be treated separately:
These differences are mostly borne out in descriptions of the two species by Hesler (1963, 1967) and Peck (1872), who originally described Entoloma conicum as having a "dull watery cinnamon" cap and stem that was "brown with white mycelium at the base."
Thanks to Jo and Bob Solem for collecting, documenting, and preserving Entoloma alboumbonatum for study; their collection is deposited in The Herbarium of Michael Kuo.
Ecology: Saprobic; growing alone or gregariously; summer; eastern North America. The illustrated and described collection is from Maryland.
Cap: 1–3 cm across; conic to broadly conic, with a prominent central "nipple"; finely, radially silky; dry; the margin not lined; white to buff.
Flesh: Thin; white.
Spore Print: Pink.
Microscopic Features: Spores 8–10 µm; predominately 4-sided; with a 1–2 µm apiculus extending from one corner; smooth; hyaline to yellowish in KOH. Basidia 4-sterigmate. Hymenial cystidia not found. Pileipellis a cutis; elements 4–6 µm wide, smooth or slightly encrusted, hyaline to yellowish in KOH. Clamp connections not found.
This site contains no information about the edibility or toxicity of mushrooms.
Cite this page as:
Kuo, M. (2019, September). Entoloma alboumbonatum. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/entoloma_alboumbonatum.html