SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a2bf00eb5e75ec47a63a7c57036ebdb6d8dfda3cb8ae8c690645b96d3e131e0' 
  AND token = 'SvqC5jK5tIEru7WthxIirrop8e9wq0tBW1+VjdIOPsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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