I have some photos that show up in gallery>picasa, but not in the photos app. I know these photos were downloaded pictures from a previous phone, off a received email I believe. I may or may not have deleted them before on the google+ photos list on the web. After switching to a new phone with the same SD card, they are still there, unable to delete in gallery because they supposedly come from picasa web. Please help.
Look here, they are all the photos uploaded into your account. you can also check this. If they are on either site, they must also be visible in google photos app (if you are connected to the internet). Don't forget to turn on sync all photos in the google photo app, aftewards they will show up or they do not exist.