Cantomaris Egg not showing it's breed despite encyclopaedia being unlocked

[Starbit]

Was mooching through my eggs today and noticed my Canto egg (which was a trade, so should be Itus) doesn't show it's breed, as if I hadn't unlocked it. 

 

However, my Encyclopedia entry for Cantos is pretty throughly unlocked.

 

I've clicked through a few Cantomaris eggs on click sites, and some say Canto, and some nothing. I suspect from this it may be an oddity like the Alt Black encyclopedia where I have to see eggs of all the alts for it to count, but all my images are unlocked, which seems a bit odd. Not a huge glitch but thought it might be worth mentioning.