Crustaceans, like Ferris the Crab, belong to the subphylum Crustacea. By analogy, then, do rustaceans belong to a subphylum named Rustacea? 
I think I'm more a Pucciniales kind of Rust.
So, then, more like the organism from which the Rust language derives its name than like the crab that serves as its unofficial mascot. 
In its biological diversity lies the strength of the community, as is often the case with ecology.
Yeah. Problem is I can't find a cute image of a Pucciniales to use as a mascot.
Strange, given that diseased plants are usually highly revered in modern Western aesthetics.
Gymnosporangium juniperi-virginianae actually looks somewhat cute. Like a little alien suffocating your apple and juniper trees.
This stage of its lifecycle seems to me the cutest of them all, and might serve as the basis of a Pucciniales mascot or cartoon character:
The photo is from the Wikipedia article linked below, and is in the public domain.
Technically, that's a gall, an abnormal part of the infected plant, not the fungus itself.
This community is weird :-).
Looks like I found the perfect ecosystem, then :-).