Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f42f9f3dd3903a7096384f1786da3b8c9df28f80bcc2c4bc11b49c1c0647d51c' 
  AND token = 'kfzxpWgmNp6lTKXzU21MsnK+cjSByaQ3NVEPN0RfhqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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