Just to go with what you have so far:
"Marcus Caelius, killed at the Battle of Teutoburger Wald, 9 AD, Lorica musculata"
Which has shoulder extensions to protect the upper arms similar to the
Marcus Favonius Facilis a Centurion from Colchester.
Clearly such an extension cannot be plate so cannot represent musculata, mail is a more likely option assuming the artist was trying to be specific.
"Titus Calidius Severus, around I century, Lorica squamata"
I wouldn't ague with that but it is a very simple representation if it is.
"Sertorius Festus, around I century, Lorica squamata"
For this you need to look at a much closer picture:
As you can be see the scales appear to be ridged this could suggest
"Lorica Plumata" a hybrid Mail/scale armour thats well attested in the archaeological record:
from
Artefacts search for "Lorica Plumata":
Occurences:
1 : Augsburg, Kornhausgasse [BY] (DE) (Droberjar, Peška 2002, Liste 2, p.138-140, n°4)
2 : Hebron (IL) (Droberjar, Peška 2002, Liste 2, p.138-140, n°5)
not Hamata Squamata!
3 : Mandeure, Epomanduodurum [25] (FR), Besançon, Musée des Beaux-Arts et d'Archéologie, inv. 855.1.231 (Droberjar, Peška 2002, Liste 2, p.138-140, n°6)
4 : Newstead [Nottinghams.] (UK) (Droberjar, Peška 2002, Liste 2, p.138-140, n°2)
5 : Ouddorp, Gem. Gouderreede (NL) (Droberjar, Peška 2002, Liste 2, p.138-140, n°8)
6 : Roma, env (IT) (Droberjar, Peška 2002, Liste 2, p.138-140, n°1)
7 - 8 : Usk, Fortress (UK) (Droberjar, Peška 2002, Liste 2, p.138-140, n°7, 8) (2 ex.)
9 : Vize (TR) (Droberjar, Peška 2002, Liste 2, p.138-140, n°3)
Publications:
"
Lorica Hamata Squamataque A Study of Roman Hybrid Feathered Armour" Martijn A. Wijnhoven.
"
Putting the Scale into mail, Roman Hybrid Feathered Armour" Martijn A. Wijnhoven.
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