They look like common lawn and garden variety (Agaricus or Leucoagaricus probably) that are non-poisonous to people, but was wondering if tortoises process them differently.
If your right about the type, then they are safe for the torts.
Native Americans believe they should not eat the box turtles, because they knew they ate mushrooms which were poisonous to man and said that the poison was able to be passed on to man thru the meat.
As for torts liking them, almost all the hingebacks seem to think they are candy (except of course my stubborn group of Homes ).