Insect life at Igloo Lake

Above the male of Leptophlebia cupida mayfly captured in imago stage. It was not easy to determinate the adult may flies at Igloo Lake around the end of June. I knew it was a Leptophlebia species but I was not sure which one. I was guessing for the Leptophlebia nebulosa but once home in the Netherlands it had to be verified by Steven Burian at Connecticut state university to be 100% sure. I was correct with a Leptophlebia species but the adult mayflies in the pictures taken around Igloo Lake Lodge are all Leptophlebia cupida, a closely related species to nebulosa. I shot male and female and sub imago and imago. Now we know the exact species that so abundant at Igloo lake around the end of June, we can really match the hatch perfectly and hopefully it will led to catching more fish too! (see the fly tying pages) The fisherman's name for the adult male is the Black Quill Mayfly Dun for sub imago and and Black Quill Mayfly spinner for the imago.

Oh......  for those who not so familiar with insects there are three easily observable features that can be used to determine the different sexes in the winged stages of mayflies:
1) Eyes of male tend to dominate the head; eyes of female don't.
2) Fore legs of male are extremely long; fore legs of female aren't.
3) Male has forceps (claspers) to hold female during copulation; female doesn't.

While not all three of these features will be always observable, usually one or two are, and can be used to determine the sex between a male or female of a winged mayfly.

Difference between Dun and Spinner
Mayflies are unique in the insect world and usual have more than one winged life stage, the dun (sub-adult or sub imago), and the spinner (adult or imago). Under most circumstances, the (dun or spinner) determination is easy to make by watching the wings real closely.
1) A mayfly dun (sub imago) has wings that are dull and opaque.
2) A mayfly spinner (imago) has wings that are shiny and transparent.

Beautiful close up picture from the male imago of the Leptophlebia cupida

This picture taken at the end of the big may fly hatch at Igloo Lake, I just missed the main hatch by a week.

Beautiful picture of the male imago of the Leptophlebia cupida

Beautiful picture of the male imago of the Leptophlebia cupida

Picture of the female sub imago of the Leptophlebia cupida with broken tails (dull wings)

Male (left) and two female sub imago (right) of the Leptophlebia cupida (notice the differences)

First hatches of the Green Drake (female)

The Green Drake (female)


Beautiful picture of the of the Leptophlebia cupida nymph


A perfect imitation of the Leptophlebia nymph




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