Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York

Blue-winged Olives
Baetis

Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.

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Male Baetidae (Blue-Winged Olive) Mayfly Dun Male Baetidae (Blue-Winged Olive) Mayfly Dun

Lateral view of a Male Baetidae (Blue-Winged Olive) Mayfly Dun from Mystery Creek #308 in Washington

This dun emerged from a mature nymph on my desk. Unfortunately its wings didn't perfectly dry out.

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27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.

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Identification: Key to Species of Agnetina Adults

Couplet 1
Full Key at a Glance

Adapted from Stark et al (1986)

Option 1	Option 2
Femora transversely banded Anterior view of femur of Agnetina annulipes. Figure source: Stark et al (1986)	Femora longitudinally banded Dorsal view of middle and hind femora of an Agnetina capitata male. Figure from this Male Agnetina capitata adult. Anterior view of femur of Agnetina capitata. Figure source: Stark et al (1986) Anterior view of femur of Agnetina flavescens. Figure source: Stark et al (1986)
Male hemitergal process foot-shaped with long slender ankle and toe Lateral view of hemitergal process of male Agnetina annulipes. Figure source: Stark et al (1986)	Male hemitergal process either with toe blunt or ankle short Lateral view of hemitergal process of male Agnetina capitata. Figure source: Stark et al (1986) Lateral view of hemitergal process of male Agnetina flavescens. Figure source: Stark et al (1986)
Female subgenital plate truncate, dark pigment covers sternum 8 in continuous mesal band Sterna 8 and 9 of female Agnetina annulipes. Figure source: Stark et al (1986)	Female subgenital plate rounded with areas of basolateral dark pigment Sterna 8 and 9 of female Agnetina capitata. Figure source: Stark et al (1986) Sterna 8 and 9 of female Agnetina flavescens. Figure source: Stark et al (1986)
	Remaining species: Agnetina capitata and Agnetina flavescens
source	source
	2 Example Specimens Male Agnetina capitata (Golden Stone) Stonefly Adult Male Agnetina capitata (Golden Stone) Stonefly Adult 11 Pictures Male Agnetina capitata (Golden Stone) Stonefly Adult Male Agnetina capitata (Golden Stone) Stonefly Adult This stonefly emerged in my aquarium, and unfortunately I severely damaged its wings just trying to catch it. It's still an interesting specimen, especially since I was able to also photograph the nymphal shuck it emerged from. I was surprised by just how light it was shortly after emerging. I photographed it a couple days later when it had darkened considerably; it was a pale, almost pastel yellow at first. 9 Pictures
Agnetina annulipes	Go to Couplet 2

Adapted from Stark et al (1986)

The current couplet is highlighted with darker colors and a icon, and couplets leading to this point have a icon.

Couplet 1

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Couplet 1 (You are here)

Leads to Agnetina annulipes:

Femora transversely banded
Male hemitergal process foot-shaped with long slender ankle and toe
Female subgenital plate truncate, dark pigment covers sternum 8 in continuous mesal band

Agnetina annulipes

Leads to Couplet 2: