The femur of this Isonychia bicolor mayfly spinner is highlighted in red.

Caption

The femur (
The femur of this Isonychia bicolor mayfly spinner is highlighted in red.
The femur of this Isonychia bicolor mayfly spinner is highlighted in red.
Femur: The main segment of an insect's leg close to the body, in between the tibia and the trochanter.
)
of this Isonychia bicolor mayfly spinner is highlighted in red.
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