This is a closeup of one plant in our collection of crests - Oroya borchersii crest. It's a good thing these were named before the crest occurred because it would be pretty much impossible to tell either the genus or species from the crested form.
I've been working to update our Lithops pages at the nursery during the last couple of days. The list is now updated but I'm still working on upgrading some of the image pages. The new list begins here.