Watch List notes:

Tiberius II Constantine. 578-582. AE decanummium (21.3 mm, 4.95 g, 5 h). Constantinople mint. d m CONSTANT P P A, crowned, draped, and cuirassed bust facing / Large X, cross above. SBV 436 var; DOC 20 var. VF, black patina with red highlights. 

This obverse legend should begin "d m TIB CONST..." but is lacking the TIB. Blundered legends are common during this era, but it makes me wonder if this isn't a previously unknown type for Constans II.