First, you need to make sure you are using at least LR CC 2015.1.1, or better the latest 2015.9.
If you tell your Laptop to map a letter to the WiFi share of the camera you certainly should be able to import directly.
Older card readers do not support SDXC, only up to SDHC cards. If that's the case you can use the slower SDHC (max 32GB) or use some other method to import like direct USB from camera to Laptop or WiFi (if it works stable).
Thanks for your reply McLion!
I have 2015.9
My Laptop is from March 2015. The internal card reader is a Realtek PCIE. I haven't been able to find whether it reads SDXC or not.
If I'm not mistaken, direct USB connection might work.
Simply test it with a card.
A card reader is the recommended way since with some cameras the direct USB transfer can be error prone.
However, personally I never had any issues with the direct USB connection.