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(1. picture)
photo: Szentpéteri L. József
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One of the most important parts of the picture is a mayfly partially emerging (protruding) from the water. What is immediately noticeable are the unnatural positions of its body and limbs, and the smooth water surface that indicates no movement. (1. picture).
In natural environment only preadult males and adult females emerge from the water while on the cover photo an adult male (an imago male) is trying to emerge. (The eye to front leg ratio indicates that it is an imago male.)
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(2. picture)
photo: Szentpéteri L. József
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Interestingly, none of the limbs of this adult is in physical contact with the water surface, and its front legs are in unnatural positions. One may have a hard time to explain why it does not submerge. According to our explanation, its position is kept by a black "support" that is visible on the print. (2. picture)
The undisturbed water surface is another indication that the insect is motionless. Even a small motion but a vigorously struggling insect during sloughing off its skin would definitely generate waves on the water surface.
(3. picture)
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(4. picture)
photo: Szentpéteri L. József
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(We want to point out that a live Kingfisher cannot notice and catch motionless or dead prey.) Interestingly, no more live insects are visible around the bird which is contradictory to the syncronicity. In contrast, many dead insects' limbs protrude from the water. (4. picture)
(In that part of the day that the photograph intends to illustrate, mayflies are still flying and mating in high number.)
The mass of dead insect bodies reaches such a high density where strong stream and swirling bring them together. However, the absolutely still water surface on the picture is in contrast with this possibility.
Especially high density is noticeable between the bird and its reflection with the highest density in the background where the mass of insect remains breaks the mirror effect of the water surface. On the picture that we used for illustration purposes, such an "arrangement" serves to hide the support of the bird!
Notes:
Based on the length of the front legs (compared to the size of the eyes) - a.k.a. grabbing legs - the mayfly on the picture is definitely an adult male (its colors and eye size further support this). It means that it is not emerging from the water as preadults do but rather it wants to illustrate that it is "patrolling" the water surface or just dropped into the water. If it was patrolling, then only the cercae should touch the water surface. (5. picture)
If it just fell into the water, then we can assume that it was flying before the others were flying. What could be the reason of its fall into the water? The mayfly is a clumsy flier - a gentle breeze, a water drop or a collision with another mayfly can result in it. But a healthy mayfly can always manage to take off again from the water surface; it lifts its head and thorax with its front legs while its abdomen and cercae lie on the water surface - a position that is different from the one on the picture! The crumpled wing is another interesting detail. There are two explanations for such a wing: There are males (and also females) that cannot complete the slough at the wings, or their wings are injured. These animals cannot take off, and just struggling on the water surface - preadults and females - or on the river bank! However, it is an adult on the picture in the water. How did it get there?! This animal on the picture is not hanging its middle and rear pairs of legs, instead, it keeps them in align with its body - again, an unnatural position.
Glossary:
Preadult: A transient stage that sloughs the underwater larva skin on the water surface. It sloughs again on a solid surface, and transforms into a ready-to-mate adult.
Adult: A fully developed insect that dies after mating and laying eggs.
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