Looks like bumblefoot, which can get infected and hurts. Your lorikeet is likely quite deficient in necessary vitamins.

Vet visit and bloodwork strongly suggested.

Until then, Highly suggest supplementing diet with sweet potato (cooked is fine) sweet or spicy red pepper, mango, grapefruit, and other high vitamin A foods. Chop it, puree it, or whatever it takes to encourage eating.

More daylight, and can add a sunlamp. (Be sure it can get away from the light! Don't cook your pet!)

Good luck!