Been looking at Herodian and these bits caught my eye:

Quote
[6.7.8] Such is the nature of these rivers. Alexander had brought with him many Moorish javelin men and a huge force of archers from the East and from the Osrhoenian country, together with Parthian deserters and mercenaries who had offered their help; with these he prepared to battle the Germans. The missile men were especially troublesome to the Germans: the Moorish hurl their javelins from a distance and attack and retreat nimbly, while the archers, far removed from their targets, easily fire their arrows into the bare heads and huge bodies of the Germans; but when the Germans attacked at full speed and fought hand to hand, they were often the equal of the Romans.

[7.2.1] [Summer 238] Having settled affairs in the manner described above, Maximinus led out his entire army and crossed the bridge fearlessly, eager to do battle with the Germans. Under his command was a vast number of men, virtually the entire Roman military force, together with many Moorish javelin men and Osrhoenian and Armenian archers; some were subject peoples, others friends and allies, and included, too, were a number of Parthian mercenaries and slaves captured by the Romans.

[7.2.2] This enormous force was originally assembled by Alexander, but it was increased in size and trained for service by Maximinus. The javelin men and archers seemed to be especially effective against the Germans, taking them by surprise, attacking with agility and then retreating without difficulty.

The emphasis on the number of eastern archers makes me wonder about what the list allows. Also the references to Parthian mercenaries and deserters coupled with the horse armour from Dura makes me wonder about the use of clibanarii types around this time.

Not to be a contrarian, but Parthian mercenaries could easily be horse archers.

Not contrarian at all, it is quite reasonable. However, it is the conjunction with the Dura horse armour that makes me think about some Roman clibanarii.

Well , I know you Nik, but it is difficult to creat a micro-list for every campaign or battle . 650 + lists is ...enough