Common Name
Mysterious lantern firefly
Scientific Name
Photuris mysticalampas
Recent Synonyms
None
Adult Male Size
9-11 mm
Diet
Unknown, but likely soft-bodied invertebrates
Firefly Atlas Category
Focal species
The mysterious lantern firefly is an imperiled species known from just a handful of forested peatland sites on the Delmarva Peninsula of Delaware and Maryland. It is at risk of extinction due to habitat loss and degradation associated with climate change.
Conservation
Reason(s) For Firefly Atlas Focal Species Designation
Reliably identifiable, Suspected population loss
Status
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species is an inventory of the global conservation status and extinction risk of biological species, maintained collectively by scientists worldwide.Endangered (EN)
NatureServe
The NatureServe conservation status ranks use a standardized methodology to assess the extinction risk of species, with a focus on the US and Canada. State wildlife agencies and natural heritage programs use these ranks to prioritize species for conservation actions.Globally critically imperiled to imperiled (G1G2) Not yet assessed in Delaware (SNR) Imperiled in Maryland (S1)
Species of Greatest Conservation Need Lists
Species of Greatest Conservation Need (SGCN) are lists of species included in State Wildlife Action Plans, identifying animals and plants that need the most conservation attention and resources at the state and region level.Delaware
US Endangered Species Act
The Endangered Species Act is a United States law that provides legal protections to species that are officially listed as endangered or threatened by the US Fish and Wildlife Service.Petitioned (P)
Threats
The primary threats to this species are habitat loss and degradation due to sea-level rise.
Location
Distribution
USA
Delaware, Maryland
Details
The mysterious lantern firefly occurs on the Delmarva Peninsula of Delaware and Maryland, along the Atlantic coast of the US. Its entire known range, which includes just six documented sites, occurs within two adjacent counties: Sussex County, DE, and Wicomico County, MD.
Habitat
The mysterious lantern firefly is a habitat specialist associated with high-quality forested peatland floodplains, in areas where Atlantic white cedar is often codominant.
Behavior
Activity Period
Adults are active 30–40 minutes after sunset to past midnight from mid-June to late July.
Flash Pattern
Adult males give off single yellowish-green flashes of medium luminosity typically every three to seven seconds.
Sources
Fallon, C.E. and C.M. Heckscher. 2021. Photuris mysticalampas. The IUCN Red List of Threatened Species 2021: e.T164045835A166771508. IUCN Red List of Threatened Species. Available from https://www.iucnredlist.org/en (accessed September 15, 2025).
Fallon, C. and E. Geest. 2024. Firefly Species Fact Sheet: Photuris mysticalampas. The Xerces Society for Invertebrate Conservation. 14 pp. Available at: https://www.fireflyatlas.org/threatened-species-fact-sheets/.
Geest, E., S. Selvaggio, C.E. Fallon. 2023. Petition to list the mysterious lantern firefly Photuris mysticalampas Heckscher, 2013, as an endangered species under the US Endangered Species Act. The Xerces Society for Invertebrate Conservation, Portland, OR.
NatureServe. 2025. Photuris mysticalampas Heckscher, 2013. Available from https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.902376/Photuris_mysticalampas.
