Observation: Photinus obscurellus
Primary Observer:
Katie Hietala-Henschell
Event Date:
2026-06-23
Status:
Unreviewed
Survey
Site Name:
Phyllis Haehnle Sanctuary
Province/State:
Michigan
Event Date:
2026-06-23
Time of Day:
Night-Time
Start Time:
21:49
End Time:
22:45
Number of Observers:
5
Primary Observer:
Katie Hietala-Henschell
Additional Observers:
Alex Johnson, Marty Johnson, Steve Jerant, Patrick Muldoon
target_species_genus:
photinus
target_species_species:
aquilonius
Location and Habitat
Location Accuracy (meters):
0-25
Habitat Type:
Open Freshwater Wetland - Wetland Bog, fen, freshwater marsh
Habitat Type Notes:
Open marsh with NATIVE phragmites, cattails, ferns, and standing water. Marsh was surrounded by meadow with an abundance of goldenrod, milkweed, brambles, reed canary grass, buttonbush, and Virginia creeper. Oaks were scattered throughout and present in woodland habitat.
Elevation (meters):
74
Area Searched (hectares):
0.5
Artificial Light Sources
Vehicles: No
Street Lights: No
Buildings: No
Glare from cell phone tower off site.
Street Lights: No
Buildings: No
Glare from cell phone tower off site.
Artificial Light Types
Sky Glow (diffuse illumination in the sky): No
Light Trespass (light cast on surfaces beyond its intended target): No
Glare (bright light causing visual discomfort): Yes
Light Trespass (light cast on surfaces beyond its intended target): No
Glare (bright light causing visual discomfort): Yes
Artificial Light Notes:
Bright moon casting shadows.
Observation
Observation Type:
With Flash Data
Number Observed:
50+
genus:
photinus
Species:
obscurellus
Observation Notes:
10.5 mm. Fairly abundant with approximately 100 individuals in the survey marsh area, and more beyond it. Dark pronotum.
Specimen Voucher Number:
Flash Behavior
First Flash Time:
22:09
Last Flash Time:
22:45
First Flash Temp (F):
57
Last Flash Temp (F):
55
Flashes in Pattern:
3
Flash Color:
Yellow
Flash Pattern Period:
7.25
Flash Duration:
1.25
Flash Interval:
6
Male Height Zone:
Low (0-3 ft), Moderate (3-8 ft)
Flash Location:
Flashing males were in the marsh and flying over the tops of cattails and phragmites.
Male Flash Behavior:
Early in the survey double flashes were observed. As conditions became darker and activity increased, triple flashes became the predominant flash pattern. Double and triple flashes ranged between 1-1.25 seconds and the dark interval between 5-6 seconds (more frequently 6 seconds).
Female Flash Behavior:
Females were flashing perched in the tall marsh grass.
