Large Dark Olive Mayfly vs Iron Blue Dun

Side-by-side species comparison

Attribute Large Dark Olive Mayfly Iron Blue Dun
Scientific Name Baetis rhodani Baetis muticus
Order Ephemeroptera Ephemeroptera
Family Baetidae Baetidae
Size 6-10 mm 5-7 mm
Habitat Rivers & Streams Rivers & Streams
Diet Omnivores Omnivores
Regions Europe Europe
Conservation Least Concern Least Concern

Large Dark Olive Mayfly

The most common European mayfly, emerging year-round in many rivers. It is a small olive-brown species that serves as a staple food for stream fish.

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Did You Know?

This mayfly can produce up to three generations per year, making it available as fish food in every season.

Iron Blue Dun

A small dark mayfly that hatches prolifically on cool overcast days. Nymphs are found clinging to stones in moderate to fast current.

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Did You Know?

Hatches are most prolific during rain and cold snaps, making it a favorite species for wet-weather anglers.