That is a small H.magnifica anemone.
The tentacles are short and stubby which usually indicates the anemone has recently been or is currently stressed out...usually shipping stress.
I would suggest not allowing clownfish in with the anemone and feed it very small portions regularly to build up it's strength and help it recover. Try one or two mysis shrimp to start and see if it takes them. You may need to watch it for as long as an hour in order to see it fully engulf the food item and ensure it doesnt regurgitate it.
You can bring the anemone back from shipping stress, but with a smaller anemone, it's a little tougher.
The color of the anemone is good, (a little gray, but okay overall) and the tentacle tips are without color....probably reduced ability to feed well/reduced feeding response...
Again, take it slow and feed it regularly. Clownfish and any other fish should be discouraged at this stage as they will steal food from the anemone and it cannot afford to expend energy in an attempt to eat, only to have the food stolen from it.
Search for the RC thread "Heteractis Magnifica, tell me some success stories", there is some good information there.
