SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40e22db1e365fe4b38dfb546275ebaf01007d77f964613c0f739438058c9c029' 
  AND token = 'hpnBFlCjTUK02CmVkUQuXQBAJw6QrslPIyUGRuWvMQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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