|Baetis bernus during pupation|
|The sexual dimorphism shown by Ephemeroptera|
A) Female - 2 compound eyes
B) Male - 4 compound eyes
|Net spinning Caddis - I have not been able to |
ID this specimen to species level
Back to the insects for our final subject, the feisty Alder Fly (Sialis lutaria). I say feisty, but only the nymphs are aggressive, the adult flies tend to keep themselves to themselves. The nymphs are mainly active at night, and crawl ashore to pupate. The aduts then mate, and eggs are laid on the underside of bankside vegetation that overhangs the waters edge. When the eggs hatch the nymphs fall straight into the water.