These creatures are introduced at the end of my fourth book, THE LAZARUS SPEAR. Ben calls them "creepers". They are the apex predators of the Red Place.They are just one of many deadly creatures in the sequel, which is very bad for Erwin, Tennessee.
I wanted to create a creature that paid homage to the Tasmanian Tiger, so creepers have a very long and horrifying jaw, the lower body stripes and the tail of a Tasmanian Tiger. If you don't know about Tasmanian Tigers, you can read about them here. There's also an excellent movie about them with the beautiful scenery of Tasmania (THE HUNTER). Be sure to watch the video footage (on the Wiki) of the very last Tasmanian Tiger. It's haunting to see that last Tasmanian Tiger in the cage after all the others were dead. It almost seems to sense it.
The creepers have a special jaw that opens wide like the tiger's, but they have a shorter snout than the tiger, so when the lower jaw comes up, it is pulled back by large muscles of its neck. There's a bone at the base of its jaw that acts as a pinion closing the jaws very tightly when the lower jaw is pulled back. The creepers preferred attack is to snap off limbs of prey, including humans, and then back away until the victim bleeds out.
They communicate through tail twitches.