Posted by John Carr on 28-11-2022 15:19
#12
piros wrote:
I realized that all hairs of the mystax of the "autumn" specimens are yellow. Using Engels key, this leads to Antiphrisson thalhammeri, which is considered to be a synonym A. trifarius. So the lighter autumn variant would simply be a color form of A. trifarius. But than it is interesting that all spring specimens I observed (4) look like "classic" A. trifarius, while all autumn specimens (3) belong to the thalhammeri form
I would greatly appreciate any opinion about this issue!
Greetins,
Henrik
Color of Chironomidae correlates with water temperature, so the first generation of spring is darker than the summer generation. There are other possibilities here. Maybe the two generations are reproductively isolated and have started to diverge morphologically, but not so much that taxonomists consider them distinct species.