Described as Truncocolumella rubra (Zeller 1939), later transferred to the genus Gastroboletus (Cázares & Trappe, 1991). The genus Gastroboletus accommodates a number of species with semisequestrate to sequestrate fruitbodies. These morphological forms have evolved multiple times, within different genera of boletes. Some of these species have been transferred to their ancestral genera, whiles others remain in limbo. Gastroboletus ruber linage belongs with a group of red-pored boletes, and will be transferred soon (J. Frank et al. in ed.).
Gastroboletus ruber is currently known from ~50 locations; mostly in the Pacific Northwest. There are six known populations in California, but no new records since 1980.
Uncommon based on reports, this species appears to be under reported due to the summer or early fall fruiting, at high elevation locations. Population appears stable in the PNW, CA populations need to be revisited.
It could either be listed as Data Deficient (DD), pending CA revisits, or Least Concern (LC), based on PNW population.
Known from mostly high-elevation locations in the Northern Sierra Nevada of California, and mid- to high-elevation locations in the Cascade Range in Oregon and Washington, USA.
Population appears stable in the northern part of the range; a number of observations are being made by casual observers (http://www.inaturalist.org 2020) in recent years. Also ‘common in the Cascades of Washington at the right time of year’ (S. Adams, J. Ammirati pers. comm.).
There are currently six known California locations; but no new collections have been made since 1980 (Siegel et al. 2019). Historic California populations should be revisited, as the decline of reports coincide with H.D. Thiers and W. B. Cooke no longer collecting in the area. (MyCoPortal 2020).
Population Trend: Stable
Solitary, scattered or in small clusters; fruitbodies forming underground, erupting from duff, but typically remaining partially buried when mature. Ectomycorrhizal, associated with Pinaceae; especially Mountain Hemlock (Tsuga mertensiana) and fir (Abies spp.). Fruiting in summer and early fall, typically after thunderstorms or summer rains in mid to high elevation forests. This species is likely dependent on mycophagy (primarily eaten by small mammals) for spore dispersal.
Prolonged droughts and decades of fire suppression have drastically altered the high sierra forest, leading to thicker, denser, Abies dominated forest. As a result, hotter, stand replacing fires (rather than patchwork and understory burns) are commonplace, altering appropriate habitat drastically, and making it ill-suited for this species.
Revisit historic populations in California, and note presence or absence of Gastroboletus ruber.
Cázares, E. and Trappe, J.M. 1991. Alpine and subalpine fungi of the Cascade and Olympic Mountains. 3. Gastroboletus ruber comb. nov. Mycotaxon 42: 339–345.
MyCoPortal. 2020. Mycology Collections Portal. Available at: http://mycoportal.org
Siegel, N., Vellinga, E.C., Schwarz, C., Castellano, M.A. and Ikeda, D. 2019. A Field Guide to the Rare Fungi of California’s National Forests. Bookmobile: Minneapolis, MN. 313 p.
Zeller, S.M. 1939. New and noteworthy Gasteromycetes. Mycologia 31: 1–32.