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American March Browns

Like most common names, "American March Brown" can refer to more than one taxon. They're previewed below, along with 5 specimens. For more detail click through to the scientific names.

Mayfly Species Maccaffertium vicarium

These are often called American March Browns.
In the East and Midwest this is one of the most important hatches of the Spring. They are large flies which emerge sporadically, making for long days of good fishing.

This species contains the two classic Eastern hatches formerly known as Stenonema vicarium and Stenonema fuscum, the "March Brown" and "Gray Fox." Entomologists have discovered that these mayflies belong to the same species, but they still display differences in appearance which the trout notice easily. Anglers should be prepared to imitate both types.
Maccaffertium vicarium (March Brown) Mayfly NymphMaccaffertium vicarium (March Brown) Mayfly Nymph View 5 Pictures
Collected April 19, 2006 from in
Added to Troutnut.com by on April 21, 2006
Male Maccaffertium vicarium (March Brown) Mayfly DunMale Maccaffertium vicarium (March Brown) Mayfly Dun View 10 PicturesI collected this mayfly on the same trip as a female of the same species. After these photos it molted into a spinner. This is the form of Maccaffertium vicarium which anglers call the "Gray Fox."
Collected May 28, 2005 from in
Added to Troutnut.com by on May 24, 2006
Female Maccaffertium vicarium (March Brown) Mayfly SpinnerFemale Maccaffertium vicarium (March Brown) Mayfly Spinner View 7 PicturesI collected this mayfly on the same trip as a male of the same species. They are Maccaffertium vicarium mayflies of the type formerly known as Stenonema fuscom, the "Gray Fox."
Collected May 28, 2005 from in
Added to Troutnut.com by on May 24, 2006

Mayfly Species Litobrancha recurvata

These are very rarely called American March Browns.
Litobrancha recurvata is generally reported to be the largest North American species of mayfly in angler entomologies, though this understanding is being challenged by reports of Hexagenia limbata that may exceed 40mm in some locales. Regardless, it is certainly the largest mayfly in the region of its distribution. Sometimes it appears together with species of Hexagenia or Ephemera, but in other places it creates excellent action on its own.
Female Litobrancha recurvata (Dark Green Drake) Mayfly DunFemale Litobrancha recurvata (Dark Green Drake) Mayfly Dun View 2 PicturesThese photos were contributed by Spencer Vanderhoof.
Collected May 15, 2010 from in
Added to Troutnut.com by on March 3, 2012
Male Litobrancha recurvata (Dark Green Drake) Mayfly SpinnerMale Litobrancha recurvata (Dark Green Drake) Mayfly Spinner View 1 PicturesThese photos were contributed by Spencer Vanderhoof.
Collected May 15, 2010 from in
Added to Troutnut.com by on March 3, 2012
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