Actually, propithecus verreauxi coronatus is now reckognized as it's own individual species so this is a crowned sifaka (propithecus coronatus) while verraux's sifakas (propithecus verreauxi) look quite different. Trust me, I did a lot of research on this
Ah yes, I was young and inexperienced back then (2008) I have just been to Madagascar and have therefore done a lot of research on lemur species and seen three different sifakas myself (crowned, verraux's and coquerel's). The one that is currently my avatar is a verraux's sifaka so you can see the difference.
I did behavioural, group composition and habitat studies of collared brown lemurs as well as researching and monitoring the biodiveristy levels of the littoral rainforest in the south east of Madagaskar