I’m on vacation, so please accept my apologies for the brief entries. — Daniel.
Pinkthroat morning-glory is native to northern and central Mexico, and southwestern USA. The name Ipomoea means “like a worm”, referring to the twining habit of many members of this genus (thanks to Calflora.net for the definition). You can get a sense of what is meant by viewing the Ipomopsis photographs (particularly Ipomoea cristulata) on the web site of Erik Enderson.