Photuris lucicrescens

Life cycle

Beetles such as P. lucicrescens go through four life stages: egg, larva, pupa, and adult. Photuris fireflies spend the majority of their lives as larvae, which are bioluminescent. Larvae are predaceous, eating snails, worms, and other soft-bodied invertebrates. Adults appear in mid-summer, from June to August.

Behavior

Adult male P. lucicrescens fireflies fly over vegetation about 45 minutes after sunset and later, flashing to attract the attention of females. Their crescendo flashes are usually coming from low vegetation, sometimes from poising individuals and sometimes from a zig-zag flight pattern. Their flash pattern is very distinctive, with a long, very bright greenish flash with a duration of 0.75 to 2.5 seconds, increasing in intensity enough to illuminate several feet around the beetle, before ending abruptly. The firefly is dark for 5 to 10 seconds before it flashes again. Unlike some other species, P. lucicrescens, mainly relies on neurological input for the timing of the flash rather than by natural rhythmic calcium-controlled activity in the lantern cells. Calcium may still help activate the light-producing reaction inside the cells, but it does not cause the lantern tissue to flash on its own.

In addition to the prominent crescendo flash, males also have a flash pattern that consists of a single, shorter flash, which is approximately 1/10th of a second with intervals of 3-5 seconds , which is easily confused with flashes of other Photuris species. These flashes usually occur in tree canopies rather than low vegetation A female responds with an answering flash from low vegetation. Females also use "aggressive mimicry" to lure other species of fireflies in order to eat them. Because of this behavior, P. lucicrescens are one of the species known as "femme fatales". No other mid-Atlantic or northeastern Photuris species has such variable flashing patterns

It appears that the typical crescendo’s occur earlier in the season (June) and transition to more varied patterns around July in place of the typical crescendo .

Habitat

Photuris lucicrescens is primarily associated with moist, forested floodplain habitats, which are believed to serve as its main breeding environment. While commonly associated with these areas, individuals may disperse beyond them, especially later in the season, and can be found in adjacent forest and edge habitats. Females in particular occupy a broad range of environments, including open fields and wooded areas, in conditions that vary from dry to moderately moist and across elevations from valleys to mountainous regions. In some regions, this species is also found near developed areas close to floodplains, where it may occasionally appear in suburban yards.

Range

Photuris lucicrescens has a broad distribution in eastern North America, occurring in both the United States and Canada (Ontario). Its range spans much of the eastern U.S., from southern New England southward through the Mid Atlantic and Coastal Plain to the Carolina's, and westward into Tennessee, northern Georgia, and Arkansas. It is also reported across much of the central Mississippi Valley and extends into portions of the upper Midwest, including areas such as Michigan and Wisconsin.

The species is less consistently recorded in parts of central Pennsylvania and some adjacent northern regions, though it is likely present along much of the Appalachian corridor from Maryland south through West Virginia, Virginia, and Tennessee. Overall, the species occupies a large range, with an estimated extent of occurrence exceeding 2 million km².