There is an image going around that is supposedly from a Tyranid playtest set of rules. While this is most likely not a real set of rumors, it's worth posting in the chances that it's real. Lets take a look at the images.
The first one above is the image that is circulating as of early this morning, and the second is a conversation that includes talk of a Genecult codex.
Please remember that info like this is most often not real, so take with salt.
These originate on a Tyranid Facebook group.