Big Dipper Firefly

§ Quick facts

§ Encyclopedia

Photinus pyralis, also known by the common names the common eastern firefly or big dipper firefly, and sometimes called a "lightning bug", is a species of flying beetle. An organ on its abdomen is responsible for its light production. It is the most common species of firefly in North America, and is typically found east of the Rocky Mountains. Photinus fireflies are often confused with fireflies of the similar-sounding genus, Photuris, which are also found in North America.

Source: Wikipedia — Photinus pyralis · Licensed under CC BY-SA 4.0

§ Identification

Field marks. Brown with orange-yellow pronotum bearing a dark central marking; light-producing organs on last 2 abdominal segments.

Similar species. Other Photinus species (different flash patterns). Photuris (predatory "femme fatale" species that mimics Photinus flashes).

Voice. Silent.

§ Diet & behavior

Diet. Adults: rarely feed (some sip nectar). Larvae: predatory on snails, slugs, earthworms.

Behavior. Males flash specific patterns to attract mates from low foliage at dusk. Each species has a unique flash pattern. Larvae also bioluminescent in soil.

§ Range

Eastern and central US east of the Rocky Mountains

§ Habitat

Meadows, fields, forest edges, and yards with damp soil and tall grass

§ Threats

Light pollution disrupting mating signals, pesticide use, loss of damp habitat for larvae.

§ Conservation status

According to the IUCN Red List, the big dipper firefly is currently classified as Least Concern.

§ What helps

Turn off outdoor lights. Leave leaf litter in fall. Skip mosquito sprays. Mow less.

§ Further reading

• Wikipedia — Photinus pyralis
• www.nwf.org — authoritative profile of Photinus pyralis
• iNaturalist · taxon 325067
• IUCN Red List — search for Photinus pyralis
• GBIF occurrence records
• Encyclopedia of Life — Photinus pyralis

§ Sources cited

• Xerces Society Firefly Atlas
• iNaturalist
• BugGuide
• FireflyWatch