Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6da99ce46f9c3f7176816888c34cac6a6f9545fe682ec8c1e135b919426e4c59' 
  AND token = '9bJlHRGkBgZE51kKR9Y4GMDlvY0IAXbU+20QyrSdb9M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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