My butterfly guru friend, Brian (I call him my adopted grandson), came through Alpine on his way home (to CA) from a butterflying trip to Lower Rio Grande Valley. He was hoping to find an Ornythion Swallowtail, but didn't see one. However, he got this little caterpillar at Fronton, TX that appears to be that species, so he's going to try to raise it into an adult. That will be very challenging. Some of you may recall that a couple of years ago I got that species at CMO. Brian got there as quick as he could and managed to find an old dying female. He even managed to nurse her back to enough health, and fortunately she had a few eggs left in her, which he got her to lay. Of those only one survived. But shortly before it could turn into a butterfly, it too died. See posts from 9/11/13 to 10/27/13. So here's wishing him success. He thinks he learned more about raising that species since then.
Update: This is a confirmed Ornythion caterpillar. Now if Brian just has enough expertise to keep it alive. And if it wasn't diseased or parasitized before he even got it.