Fly Fishing for Trout Home
User Password
or register.
Scientific name search:

Male Malenka tina (Tiny Winter Black) Stonefly Adult Pictures

 This is the smallest stonefly I've ever collected, with a body only 5.5 mm long.

Although not in-focus in my pictures, its first tarsal segment is similar in length to the third, while the second is much shorter. This helps with family-level identification.

Examining this specimen under a microscope shows a membranous lobe on the dorsal (Dorsal: Top.) base of the cerci (Cercus: The left and right "tails" of an insect are known as the cerci or caudal cerci. The middle tail of a three-tailed insect is not.), which is the key characteristic in Merritt & Cummins (4th ed.) to place the genus definitively as Malenka.

Following the species key in Jewett Jr's Stoneflies of the Pacific Northwest, the species appears to be Malenka tina. My dissecting microscope seems to show sternite (
One sternite of this Isonychia bicolor mayfly spinner is highlighted in red.
One sternite of this Isonychia bicolor mayfly spinner is highlighted in red.
Sternite: The bottom (ventral) part of a single segment on an insect's abdomen.
9 ending in a rounded knob, which distinguishes it from Malenka bifurcata, but the detail is hard to work out.

Also worth noting is that Montana appears to have this species, whereas birfucata is not know there:

This stonefly was collected from the Madison River on July 1st, 2019 and added to on July 18th, 2019.

Start a Discussion of this Adult:

You must log in at the top of the page to post. If you haven't registered yet, it's this easy:

Username:          Email:

Password:    Confirm Password:

I am at least 13 years old and agree to the rules.
Top 10 Fly Hatches
Top Gift Shop Designs
Top Insect Specimens
Miscellaneous Sites