Observation: Pyractomena

Observation: Pyractomena

Primary Observer:

Pam Morgan

Event Date:

2025-05-14

Status:

Unreviewed

Survey

Site Name:

Bentonville near SW Elm Tree Rd

Province/State:

Arkansas

Event Date:

2025-05-14

Time of Day:

Night-Time

Start Time:

21:05

End Time:

22:05

Number of Observers:

1

Primary Observer:

Pam Morgan

Additional Observers:

NA

Target Species Genus:

Pyractomena

Target Species Species:

dispersa

Location and Habitat

Location Accuracy (meters):

25-50

Habitat Type:

Grassland/Meadow - Meadow, open, grasses dominant

Habitat Type Notes:

Horse pasture / field. Grass dominant, with some wildflowers. Dogbane coming up right now. Field is bordered by trees, then houses. Trees are sassafras, black cherry, elm, hackberry, red cedar and some invasives including Bradford pear. The tree border has an overgrown shrubby/vine layer, including grapevines, multiflora rose, green briar, and blackberries.

Elevation (meters):

351

Area Searched (hectares):

.2

Artificial Light Sources

Vehicles: Yes
Street Lights: Yes
Buildings: Yes

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): Yes

Artificial Light Notes:

The field is bordered by houses, some of which have their porch lights on. When a car enters the street (not very often), its headlights shine into the field. There is a streetlight about 50 meters from the field and its light shines into part of the field.

Observation

Observation Type:

Flashing

Number Observed:

1

Genus:

Pyractomena

Species:

unknown

Observation Notes:

12 mm long. Over long grass in field. May be the same as the suspected Pyractomena dispersa also seen in this field, but this one looks a little different (flared pronotum). I caught it because it had a different flash pattern also - same timing as the others in the field - 1-second faint orange flicker flash, then 2 seconds of darkness, but this one was flying straight down when flashing. Then the next flash started at the same height as the beginning of the previous one, so it must have flown up diagonally while dark. Straight down for every flash. It was the only one I saw doing this, although the other fireflies had erratic flights.

Specimen Voucher Number:

Flash Behavior

First Flash Time:

22:05

Last Flash Time:

22:05

First Flash Temp (F):

81

Last Flash Temp (F):

81

Flashes in Pattern:

>4

Flash Color:

Orange

Flash Pattern Period:

3

Flash Duration:

1

Flash Interval:

2

Male Height Zone:

Moderate (3-8 ft)

Flash Location:

Over long grass in field. About 3 feet high.

Male Flash Behavior:

1-second faint orange flicker flash, then 2 seconds of darkness, flying straight down when flashing. Then the next flash started at the same height as the beginning of the previous one, so it must have flown up diagonally while dark. Straight down for every flash. It was the only one I saw doing this, although the other fireflies had erratic flights.

Female Flash Behavior:

 

Leave a Comment

Connect

Sign up for our newsletter to receive updates.

Follow

Follow the Xerces Society.

Share

Share this page.

Support

Support the Xerces Society's conservation work.

This is a project of the Xerces Society, working in collaboration with the IUCN SSC Firefly Specialist Group and New Mexico BioPark Society.

Copyright © 2025 The Xerces Society •1631 NE Broadway Street, #821 • Portland OR 97232 USA