A comprehensive illustrated digital key is provided for the 23 species of Lampyridae found in eastern Canada. Photinus consanguineus Leconte, Photinus sabulosus Green, and Lucidota punctata (LeConte) are added as new Canadian records, and Photinus ignitus Fall and Photinus indictus (LeConte) are added as new Quebec records. Phosphaenus hemipterus Fourcroy, Photinus curtatus Green and Photinus pyralis Linnaeus are added to the list of Ontario Lampyridae, while Photinus punctulatus LeConte and Photinus scintillans (Say) are deleted from the list following re-identification of specimens on which previous records were based. The key will also allow the identification of most species of firefly occurring in the northeastern United States.

Lucidota atra Photo by S.A. Marshall

The Lampyridae, or fireflies, are familiar to almost everyone for the brilliant bioluminescence these common beetles use for sexual communication, aposematic signalling and (in some cases) mimicry of prey species in the same family. Despite this familiarity, and the ubiquity of fireflies in populated areas of North America, species can be very difficult to identify. Now that there is widespread concern about the impact of light pollution and habitat loss on fireflies, there is new incentive to examine regional lampyrid faunas and to develop userfriendly tools for the identification of important species. Fireflies are now generally difficult to identify to species because most existing identification keys are incomplete and poorly illustrated; furthermore, many important keys are in the older primary literature and relatively difficult to obtain. No published monographs or keys specifically treat the northeastern Lampyridae. The current review was prompted by a need to render the firefly fauna of Ontario readily identifiable. According to McNamara (1991), 19 of Canada’s 29 species of Lampyridae have been recorded from Ontario. We here confirm the presence of 17 of those species based on a new study of some 5000 specimens, and add a further six species and one genus not previously recorded from Ontario. Two species are also noted as new records from Quebec. Two species reported by McNamara (1991) are found to be based on misidentifications, and are excluded from our list of 23 Ontario firefly species.

To identify firefly species on the wing (Lloyd 1969).
Fireflies are widely considered to be in decline in many parts of North America, but this perception seems to be based largely on anecdotal evidence, and there are few studies on actual losses of identified species due to specific causes. The loss of wetlands is conjectured to be a major factor because of the palustrine associations of many species. Light pollution is also considered to be a disruption
to firefly flash communication. Conservation is hampered by an inability to assess local firefly assemblages, a consequence of the taxonomic difficulty of the group and the poor representation of many species in collections.