SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdd4b6d08b26d1581efae581e87fa78ee720e53af3cef632ab82bc9e19cb4b97' 
  AND token = '/wmF6IjGq+UcEXuuw+BFxnwCa0FRg5BPEjpSEnY5kVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}