Beware, a tachyon-like object is different from a tachyon. It is an object that under specific circumstances behaves as if it would be a tachyon (it consists in an effective description). An elementary particle that is a tachyon is a different story. I had the latter in mind when answering.

To summarise, we compare apples with pears here (I know that from very far, an apple looks like a pear; they are however not the same ;) ).