You do not have to strictly follow these anatomy guidelines if you can't,
I know a lot of people are more comfortable with drawing them in a more canine way, which is fine.

All of the arcanus traits:
http://arcanus-ethora.weebly.com/raritytraits.html

Body types and races:
Arcanus Body types and Races

a anthro guide:
http://www.furaffinity.net/view/21340323/

the group :
http://www.furaffinity.net/view/21261279/

The info about the species :
http://arcanus-ethora.weebly.com/

They're a closed species right now, they will become semi open soon !!