Starcraft 2 patch 16 question

[arepakiller]

I was searching on the new Starcraft 2 patch 16, and looking on the mpq file patch.SC2archive under units there is something called Symbiote under the zerg units, is that a new unit? (Since I don't have a complete knowledge about these files) this Symbiote have its deaths animations on m3 file, under Terran I found a SPIDER MINE.m3 file and a magnetic mine.m3 file. Also I Just found on structures something called Psi Indoctrinator under Terran Structures. I don't want to rise false speculations but are those new? or they were   included previously? I would appreciate any your answers.