Lol! I don't really see the Empire naming their trooper types in that sense. They're all stormtroopers, with various sub-types for a variety of roles.
My version of a handbook to the Imperial Forces, using only what can be deduced from the films as the backbone, and adding only the EU stuff that doesn't get that source material wrong, has things like:
(in the "Phase 3" section -- i.e., the OT troopers)
*ahem*
"Stormtrooper armor, extreme environment, hot" for the stuff specially outfitted for extended deployment in a hot desert -- fewer gaps for sand or dust to get into the armor's workings, augmented climate-control systems, with an emphasis on cooling, etc. It's not just the pauldrons. The ab plate is different, the left knee plate is different, the shoulder straps are the same canvas as the underbelt and not plastic, the "tears" on the helmet don't have the lines... My listing notes that Stormtroopers and the Imperial Starfleet officers over them tend to refer to it as "desert gear", and civilians, fringers, and Rebels have coined the term "Sandtrooper".
I went through a bit with that and the Snowtrooper gear, because so many terms we use are vague (deserts can be both hot and cold, so that alone isn't an indicator) or Earth-centric ("arctic" refers not to temperature, but to the Greek word for "bear", "
arktos", being the constellations associated with the far North). So I had to come up with something specific, sterile, and non-slangy.
That said...
If snowtroopers, sandtroopers, scouttroopers, etc. nomenclatures are even canon at all, they do describe their mission type at least. I would have no idea what a Scarab trooper would even be if I hadn't read about it.
They collect dung and roll it into large balls...? I'm hoping it ends up either being a production nickname or a specific name for that unit. I actually hope the armor itself is commando armor, anintermediate stage between the Imperial Commandos we have right after Episode III and the Storm Commando developed after the Battle of Yavin.
Which reminds me. I still have no idea what that black helmet/armor is, but I don't like it. I hope it's for a specific character, and
not new commando gear.
--Jonah