The the mysterious lantern firefly (Photuris mysticalampas) was proposed for listing in 2023 through a petition submitted by the Xerces Society. The mysterious lantern firefly, a native species endemic to the Delmarva Peninsula of Delaware and Maryland, is associated with high quality forested peatland floodplain habitats. It is known from only six sites in two watershed. As a habitat specialist, the mysterious lantern firefly is threatened by habitat loss, fragmentation, and degradation. It is not known to disperse very far, and its nocturnal courtship behavior makes it especially vulnerable to light pollution. Sea level rise and increased storm surges along the Atlantic Coast are a threat to this species, as is widespread pesticide use and the spread of invasive plants throughout its habitat. Despite dedicated search efforts, this firefly has been found in only a few sites.