Late Roman Unit Sizes

[Macedon]

Arrian has some of his legionaries armed with the lancea, and it seems possible that his soomatophylakes or lonchophoroi are intended to be lanciarii, who in turn are mentioned elsewhere as serving in a bodyguard role.

I would be very reluctant to equate the term logche with the lancea or the term logchophoroi with the lanciarii. It unfortunately seems that both terms are used very broadly in Greek. Is it the same in Latin?

Also, just because they're called Auxiliaries doesn't mean they are. That kind of thing happens all the time in Roman literature. Like Greek authors calling legionnaires Phalangites for example.

What are the auxiliaries then exactly? Following the same line of thinking, they might exist under different names in which case one could as well call them auxiliaries.