Latenivenatrix

That is, one of the two species, along Stenonychosaurus, which were incorporated into Troodon. Yes, now Troodon is suggested to be potentially a nomen dubium (as of being only based on teeth which are undiagnostic among troodontids). I'm sorry guys, but sooner or later it would have to happen. While I'm more skeptical about Stenonychosaurus validity (no clearly diagnostic traits have been defined), Latenivenatrix has a nice, unique combination of traits, and a very particular pubis, that reminds a bit of cohabitant Hesperonychus (they are clearly different, though). That would be interesting as classifying Hesperonychus among troodontids (instead of microraptorians) would be so much better in line with geo/stratigraphic consensus.

At the moment, Latenivenatrix and Stenonychosaurus are kept separate due to differences residing in size, third metatarsal and frontal bones anatomy, even though I'd not be surprised if someone will wake up interpreting Latenivenatrix as the male form of Stenonychosaurus (which in this case would have nominal priority) but I've already spoken enough of these things with oviraptorids stuff so whatever 

Interestingly, such a large size (3.5 meters) has never been disclosed for ex-Troodon. It seems like only Stenonychosaurus morphotype was "culturally" used to give a max. length estimate (which was 2.4 meters).

Oh well, I'll be sorry for the train conductor but at least we have a giant troodontid now (even if we always had it virtually).