Tokom istraživanja vilinih konjica na području sjeverne Bosne otkrili smo i treći lokalitet vrste C. tenellum u slivu rijeke Save/Dunava u BiH. Veliki broj primjeraka pronašli smo na jezeru formiranom na starom površinskom kopu rudnika željezne rude nedaleko od Prijedora. C. tenellum je rijetka vrsta na Balkanu koja donedavno nije bila poznata za područje sliva rijeke Dunav.

The third locality of C. tenellum in the Sava/Danube River catchment in Bosnia and Herzegovina was found during recent field investigations in North Bosnia. Numerous individuals and copula were found at a small outflow of one of artificial lakes left after iron ore extraction. C. tenellum is rare in the Balkans and until recently it was not known from the area north of the Dinaric Alps that belong to the Danube River catchment.