
Western jack-o’-lantern
Omphalotus olivascens
An orange to olive-toned mushroom that often grows in clusters from wood or buried roots. It is toxic and can be mistaken for a chanterelle.
- Family
- Omphalotaceae
- Regional status
- Review pending
- Habitat
- Hardwood stumps & buried roots
- Safety
- Poisonous
A closer look.
MykoWeb describes true gills and an association with hardwood stumps or roots. The resemblance to chanterelles makes superficial color matching especially unsafe. This species can cause severe gastrointestinal illness.
MykoWeb · Michael Wood & Fred Stevens ↗ · National Capital Poison Center ↗
Compared with linked references on October 22, 2026. This is source verification, not independent expert review or an identification guarantee. Seasonal tags are approximate. Specimen maps show a selected historical subset.
Through the seasons
MykoWeb describes fruiting from late autumn through midwinter. Local conditions and rainfall affect timing.
Knowledge has a context.
Historical accounts are presented as attributed records, not endorsed practices, medical advice, or permission to harvest.
No reviewed cultural account is included. This record focuses on documented toxic lookalike risk.
A record of where it was found.
Documented in California, often associated with hardwood stumps and buried roots. The specimen snapshot records collections rather than an inferred continuous range.
Hardwood stumps & buried roots
Northern California · Central California · Southern California
Historical collections are evidence of recorded locations, not a continuous range, current presence, abundance, native status, or confirmed identification. Unmapped places are not evidence of absence.
What this map includes
From the first 64 results returned by the stored GBIF query, 53 specimens met the coordinate and reuse filters; 11 were excluded. The query matched 64 records at retrieval. This subset is not random or exhaustive.
Records are labeled California, have coordinates, and lack GBIF geospatial-issue flags. We exclude known coordinate uncertainty above 25 km and use only CC0 or CC BY 4.0 records. 8 included records do not report coordinate uncertainty. A 0.25° cell is about 28 km north to south; it does not show an exact collecting site.
Matched taxon: Omphalotus olivascens ↗.
Inspect the stored query ↗ · Download the attributed snapshot ↓
MykoWeb · Michael Wood & Fred Stevens ↗ · National Capital Poison Center ↗
Data publishers & selected records
Dataset citations apply to the contributing specimens. The snapshot retains record IDs, original ownership, and reuse licenses; coordinates are generalized to a quarter-degree grid.
- University of Tennessee Fungal Herbarium ↗
University of Tennessee Herbarium (2026). University of Tennessee Fungal Herbarium. Occurrence dataset https://doi.org/10.15468/da30il accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- University of Illinois, Illinois Natural History Survey Fungarium - Fungi ↗
Illinois Natural History Survey (2026). University of Illinois, Illinois Natural History Survey Fungarium - Fungi. Occurrence dataset https://doi.org/10.15468/4eknz8 accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- San Francisco State University, Harry D. Thiers Herbarium ↗
Harry D. Thiers Herbarium (SFSU) (2026). San Francisco State University, Harry D. Thiers Herbarium. Occurrence dataset https://doi.org/10.15468/zvmmvn accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- Cornell University Plant Pathology Herbarium ↗
Cornell Plant Pathology Herbarium (CUP) (2026). Cornell University Plant Pathology Herbarium. Occurrence dataset https://doi.org/10.15468/xzn5g5 accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- Field Museum of Natural History (Botany) Fungi Collection ↗
Grant S, Webbink K, von Konrat M (2024). Field Museum of Natural History (Botany) Fungi Collection. Version 4.14. Field Museum. Occurrence dataset https://doi.org/10.15468/x2hjnp accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- University of Washington Herbarium (WTU) - Macrofungi Collection ↗
Giblin D (2025). University of Washington Herbarium (WTU) - Macrofungi Collection. University of Washington Burke Museum. Occurrence dataset https://doi.org/10.15468/ajny5r accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/licenses/by/4.0/legalcode · accessed October 26, 2026
- USDA United States National Fungus Collections ↗
USDA-ARS US National Fungus Collection (2026). USDA United States National Fungus Collections. Occurrence dataset https://doi.org/10.15468/w78rwb accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- The New York Botanical Garden Herbarium (NY) ↗
Ramirez J, Watson K, Feder L, Gjieli E, Sessa E (2026). The New York Botanical Garden Herbarium (NY). Version 1.104. The New York Botanical Garden. Occurrence dataset https://doi.org/10.15468/6e8nje accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/publicdomain/zero/1.0/legalcode · accessed October 26, 2026
- Agaricales externi ↗
Finnish Museum of Natural History - Botany and Mycology Unit (2026). Agaricales externi. Occurrence dataset https://doi.org/10.15468/4kr67v accessed via GBIF.org on 2026-10-26.
http://creativecommons.org/licenses/by/4.0/legalcode · accessed October 26, 2026
View 53 included specimen records
- GBIF 1701209754 ↗ · 2012Field Museum of Natural History (Botany) Fungi Collection · T. Clements · The Field Museum of Natural History · License
- GBIF 5069168152 ↗ · 2000San Francisco State University, Harry D. Thiers Herbarium · T. Garrod · License
- GBIF 1701205911 ↗ · 1998Field Museum of Natural History (Botany) Fungi Collection · D. Pruden · The Field Museum of Natural History · License
- GBIF 1990328285 ↗ · 1998University of Tennessee Fungal Herbarium · NAMA · License
- GBIF 1990327408 ↗ · 1996University of Tennessee Fungal Herbarium · D.E. Desjardin et al. · License
- GBIF 1990327366 ↗ · 1996University of Tennessee Fungal Herbarium · D.L. Largent · License
- GBIF 5069167759 ↗ · 1988San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5895676849 ↗ · 1987University of Washington Herbarium (WTU) - Macrofungi Collection · Michelle T. Seidl · University of Washington · License
- GBIF 5069136053 ↗ · 1986San Francisco State University, Harry D. Thiers Herbarium · M. Seidl · License
- GBIF 5069168421 ↗ · 1986San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069136025 ↗ · 1986San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168361 ↗ · 1984San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168419 ↗ · 1984San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168300 ↗ · 1984San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167727 ↗ · 1983San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069136078 ↗ · 1982San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 4130856543 ↗ · 1982Agaricales externi · Halling, R. E. · License
- GBIF 5069167722 ↗ · 1981San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167772 ↗ · 1981San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168132 ↗ · 1981San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 1929546111 ↗ · 1980The New York Botanical Garden Herbarium (NY) · H. E. Bigelow · The New York Botanical Garden · License
- GBIF 4104568410 ↗ · 1979Cornell University Plant Pathology Herbarium · Isabelle Tavares · License
- GBIF 5069168420 ↗ · 1979San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5898538838 ↗ · 1979University of Illinois, Illinois Natural History Survey Fungarium - Fungi · W.J. Sundberg · License
- GBIF 5069136077 ↗ · 1979San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167761 ↗ · 1979San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 4099829447 ↗ · 1979USDA United States National Fungus Collections · Tavares, I. · License
- GBIF 5069167732 ↗ · 1975San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069136387 ↗ · 1974San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168126 ↗ · 1974San Francisco State University, Harry D. Thiers Herbarium · R. Halling · License
- GBIF 5069168357 ↗ · 1974San Francisco State University, Harry D. Thiers Herbarium · R. Halling · License
- GBIF 5069136065 ↗ · 1972San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 1930211782 ↗ · 1971The New York Botanical Garden Herbarium (NY) · H. E. Bigelow · The New York Botanical Garden · License
- GBIF 5069136060 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167719 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168125 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168127 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · R. Keller · License
- GBIF 5069136074 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168359 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168422 ↗ · 1970San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167737 ↗ · 1969San Francisco State University, Harry D. Thiers Herbarium · R. Keller · License
- GBIF 5069168128 ↗ · 1967San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168380 ↗ · 1966San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167743 ↗ · 1965San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168362 ↗ · 1964San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168375 ↗ · 1963San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069136115 ↗ · 1963San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069167733 ↗ · 1963San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168155 ↗ · 1962San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069136071 ↗ · 1962San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 5069168360 ↗ · 1960San Francisco State University, Harry D. Thiers Herbarium · H. D. Thiers · License
- GBIF 1928898249 ↗ · year unrecordedThe New York Botanical Garden Herbarium (NY) · O. M. Oleson · The New York Botanical Garden · License
- GBIF 4130856522 ↗ · year unrecordedAgaricales externi · Tavares, Isabelle · License
Darker = more included records, not abundance
Boundary: US Census Bureau TIGERweb ↗ · locations generalized to 0.25° cells
Trace the record.
References are attached to specific parts of this record. A citation is a route to evidence; it is not a claim that every field has completed review.
- 01California Fungi — Omphalotus olivascens ↗
MykoWeb · Michael Wood & Fred Stevens
Supports: Toxicity, wood association, and comparison with California chanterelles.
- 02Get help online or by phone ↗
National Capital Poison Center
Supports: Immediate US poison exposure advice and 1-800-222-1222 contact.
- 03GBIF occurrence records & citation guidance ↗
GBIF Secretariat and contributing data publishers
Supports: Specimen occurrence snapshot. Each contributing dataset, DOI where available, record identifier, and license is retained in the downloadable map data.
- 04TIGERweb — States and Counties ↗
US Census Bureau
Supports: Generalized California state outline only; does not imply a species distribution.