SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07964bd646ffaa9dfd963012b31207cb4e135a34dac68e5ba748bd45675f83ea' 
  AND token = '2P8CZIzAZIbqPFkOyRYjDXq+n8VXlA0/Oh7pqKOMbio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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