Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3b98f8cd7dffe59dfbd04f7f853c3537226f263b7f6d6f80ba4652816b6af40' 
  AND token = 'xIQbip71NJkvjB8tDk+G5XVaLEgmIplUE3oqfQOLQcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}