Hallo Martin!
Since two days I´ve found no more. I sent the last one to a dragonfly specialist from the nature museum Wiesbaden.
He will try to get it grown up to tell, if its the first german/middleeuropean Larve, he got for his project since some years ;-).
Before I will get my Paros, I will empty the tank and look if I´ll find any dragonfly larve any more.
But there are still left caridina simoni, one having eggs, I saw yesterday, so that will be also a sign, that the enemies have gone out…