Moesian Vexillations

I think I'm getting into the stretch drive when it comes to my book on the Moesian army (which I'm thinking of renaming - Exercitus Moesiae/Moesicae).  Many of the chapters are ready to go, and a couple need some tweaking.  Of those in need of tweaking, I think I'm about ready to do the major rewriting for one entitled, at present, "Vexillations and the Black Sea". 

I've been catching up, so to speak, on my reading on the Roman military's presence on the northwest coast of the Black Sea and into the Crimea.  There seems to have been a demonstrable military presence in a handful of cities (settlements) including Tyras, Olbia, Chersonesus, and Charax, and by demonstrable I'm thinking of the remains of fortifications, from the walls of forts to the remains of towers.  There is also evidence of the units that manned those sites, though it's more difficult to pin down when they arrived and in what quantities.

The - or a? - significant component of that contingent was comprised of vexillations, a common option from the late first century (AD) onwards.  Eventually they'd become a type of unit of their own, though that wouldn't be until late antiquity.  During the second century and into the third, vexillations were, for the most part, detachments from legions, auxiliaries, or some combination used for any one of a number of purposes (temporary reinforcement, building work), though we have little in the way of specifics about their numbers and make-up.  That hasn't stopped some, Saxer and Tully most notably, from delving into their intricacies, at least where possible.

Getting back to the lower Danube and the Black Sea, it seems that the bulk of the Roman soldiers active in the region (Tyras, Olbia, etc.) were housed in vexillations.  This I knew already.  By my 2005 reckoning, there were maybe a half-dozen to a dozen known references to vexillations in the region.  My current reckoning is well into the double-digits.  What I wasn't aware of, until a recent search on the principal epigraphic database, was the range of differently named vexillations. 

At the moment, I've found 21 different names for vexillations used/present in the region, and obviously in some cases names are used more than once.  Those names are (in the order I've found them):
vexillatio classis Ravennatis
vexillatio XII Catafractariorum
vexillatio Moesiae inferioris
vexillatio legionis V Macedonicae
vexillatio legionis I Italicae et legionis II Herculiae
vexillatio legionum I Italicae V Macedonicae XI Claudiae et cohortium
vexillatio Chersonissitanae
vexillatio exercitus Moesiae inferioris
vexillatio exercitus Moesiae
vexillatio equitum scutariorum
vexillatio Capidavensium
vexillatio expeditionis per Asiam et Lyciam Pamphyliam
vexillatio legionis VII Claudiae
vexillatio legionis XI Claudiae
vexillatio legionum I Italicae V Macedonicae et VII ad Tropaeum Traoiani
vexillatio legionum V Macedonicae XI Claudiae
vexillatio per Germaniam et Raetiam et Noricum et Pannoniam et Moesiam
vexillatio Ponticis aput Scythia et Tauricam
vexillatio Egisseis Valerius (?)
vexillatio legionum I Italicae XI Claudiae
vexillatio legionum I Italicae XI Claudiae classis Flavia Moesicae

That is a ridiculous number of vexillations for one region, at least to me and based on my earlier understanding.  On the one hand, it is perhaps easily explicable:  vexillations, by their usual understanding, were ephemeral in nature and I probably shouldn't be surprised to see such a hodgepodge.  On the other hand, it's worth stressing not just the number of different names, the different types.  Not only are there the vexillations named for the legions that they are comprised of, or even the auxiliary units, but there are vexillations named after larger armies, like the army of Moesia Inferior (or just Moesia), vexillations for places (Capidava - possibly a hint at an auxiliary unit?), vexillations named after the various places where they seemed to have been active (how else to understand per Germaniam, etc.), vexillations named after the region in which they are currently based/active (Ponticis and Chersonissitanae), vexillations for the fleet/s (Moesian and Ravennan), and a, well, randomly named one (Egisseis - not sure what's going on there and will have to look more closely). 

So, again, while I wouldn't have expected the technicality and consistency that we find, for the most part, with the names of legions and auxiliary units, I wasn't expecting this - and it was only directed towards one particular region.  Some of those names might reflect the ad hoc nature of a vexillation's creation, but perhaps some, like the "vexillatio Ponticis aput Scythia et Tauricam" and the "vexillatio Chersonissitanae", reflect the increasingly long-term character of their deployment, or that's my running theory.  Could this be pointing towards the emergence of the vexillation units that we later find in late antiquity?  Catch is those later vexillations were cavalry regiments, and names like "Ponticis" and "Chersonissitanae" don't tell us much about what kind of soldiers comprised them, and certainly not in the same way that vexillations named after legions do (legions being still primarily staffed by infantry).

Anyway, much food for thought.