About this fungus
Oak-loving Elfin Saddle is a fungus in the Helvellaceae family. Its habitat and field characteristics are summarised below.
A western North American elfin saddle with a squat, irregular dark grey to black cap and a deeply ribbed grey stem, usually appearing beneath oaks.
What to check
Look for a folded or saddle-shaped fertile surface that is nearly black, paired with a strongly grooved stem that is paler when young and darkens with age. There are no gills, ring or volva. Oak association and western North American location are important supporting evidence, but exact identification within the dark Helvella group can require microscopy or DNA.
Lookalikes
Helvella vespertina is a close western North American relative associated mainly with conifers and generally fruits earlier in the cool season. The European Helvella lacunosa name was historically applied broadly in North America, but DNA research showed that western collections include distinct species. Host tree alone is useful but not absolute proof.
Habitat and range
Mycorrhizal with oaks in western North America, especially California and nearby regions. It commonly fruits from winter into spring, rather than representing a globally distributed form of the European H. lacunosa.
Food safety
Inedible.
Photographs
Jacob Kalichman / CC BY-SA 3.0