Imago clipeata

Imago clipeata literally translated from Latin means framed portrait. It is usually used in reference to the images of heroes on Roman shields. These shield portraits were often employed in Roman military memorial statuary (sometimes hung from a tree). In later classical Roman and Italian Baroque imagery, the medallion portraits supported by nymphs or genii came to signify an apotheosis.

External reference

[http://itsa.ucsf.edu/~snlrc/encyclopaedia_romana/imperialfora/caryatids.html Description and reproduction of "Imago clipeata" at the Forum of Augustus on the Athenian Acropolis]