SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a98f9bda15cccb5d38d1f0498cd854614747685b057c0530635247cbfba22448' 
  AND token = '4p9lX77zZdx1JSQUqJfLxlPeekRq4e7wy0kfAUZBRWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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