The only Lepidoptera species given on the NHM for Gomphrena (didn't get a result using species epithet) is Eumarozia malachitana. Tortrix moths are not very big, was the pupa small?
http://www.nhm.ac.uk/our-scien...
http://mothphotographersgroup....
Some Lepidoptera species feed on a variety of plants so it could be something else, I can't enlarge your photos at the moment but this is a leaf roller and I think I can see white cocoons.. (can enlarge the 2nd pic now, not sure whether there's a pupa in there!)
