This ciliate is a nasty killer; I will soon put some Paramecium in its presence and watch...
Monodinium balbiani (FABRE_DOMERGUE,1888)
It is close to Didinium altogh it has only one cilia row. It swims very fast and usually hunt other ciliates.




Here are 2 Silver impregnation pictures please not the well stained Extrusomes and especially the "charged weapon", alias the mouth. The macronucleus is also quite massive

