Observation: Photuris

Observation: Photuris

Primary Observer:

Gordon Gueydan

Event Date:

2025-04-26

Status:

Unverified

Survey

Site Name:

Home

Province/State:

Louisiana

Event Date:

2025-04-26

Time of Day:

Night-Time

Start Time:

21:00

End Time:

22:00

Number of Observers:

2

Primary Observer:

Gordon Gueydan

Additional Observers:

NA

Target Species Genus:

unknown

Target Species Species:

unknown

Location and Habitat

Location Accuracy (meters):

50-100

Habitat Type:

Woodland/Forest - Trees dominant, and in the over-story

Habitat Type Notes:

We live in a rural neighborhood and our property is connected to 100 acres of unmitigated wetlands.

Elevation (meters):

1

Area Searched (hectares):

1

Artificial Light Sources

Vehicles: Yes
Street Lights: Yes
Buildings: No

Artificial Light Types

Sky Glow (diffuse illumination in the sky): Yes
Light Trespass (light cast on surfaces beyond its intended target): Yes
Glare (bright light causing visual discomfort): No

Artificial Light Notes:

 

Observation

Observation Type:

Flashing

Number Observed:

50+

Genus:

Photuris

Species:

unknown

Observation Notes:

There are still a few stragglers at 10:15pm. 2-3 sporadically. They peaked between 9:10pm - 9:30pm. They were synchronizing with each other between nearly ground level and 1 meter predominantly. We saw a few at least 3 meters up. We briefly walked to the back of the property to the 100 acres of unmitigated wetland, but they were not as active back there.

Specimen Voucher Number:

Flash Behavior

First Flash Time:

21:00

Last Flash Time:

22:30

First Flash Temp (F):

70

Last Flash Temp (F):

70

Flashes in Pattern:

1

Flash Color:

Green

Flash Pattern Period:

30

Flash Duration:

1

Flash Interval:

3-4

Male Height Zone:

Low (0-3 ft)

Flash Location:

Na

Male Flash Behavior:

Na

Female Flash Behavior:

Na

1 thought on “Observation: Photuris”

  1. Thanks for submitting this firefly observation, Gordon! What a neat sighting.

    Your description of abundant, low flashes that synchronized fits best with Photuris frontalis, common name “snappy single sync”. They are found in southern Louisiana, and are active around this time of year. Having a photo of a lightning bug in hand would help to confirm.

    One note about the flash pattern terminology:

    You can refer to the diagrams on the back of the Firefly Atlas data-sheet for a visual reminder of what each term means.

    For Photuris frontalis, I would expect flash pattern details that looked something like this:

    Flash pattern period: 0.75-1 second
    Flash duration: 0.1 second, very quick, or “not recorded” (It would be very hard to measure!)
    Flash interval: 0.9 seconds (flash pattern period minus flash duration)

    I know these terms can be confusing, but they are necessary because of fireflies with more complex flash patterns (for example ones with long glows or multi-pulse flash patterns).

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