SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04532733b434607c878e03212ca16d4bc6fa892c74a742e8d82112079e1845ab' 
  AND token = '0jkmCw4RTw7wKvq1Y0jug+XjXyWlZ9LT+UG0LhqepHM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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