Handbook of British Chronology, 508: Constantine was the 'son of Macduff' and styled earl of Fife probably before 1124 and died between 1128 and 1136.
Constantine is the first earl of Fife on record, appearing as earl on a charter dated before 1107, and later recorded as great judex in Scotia. His last appearance is c.1128 and was succeeded by Gillemichael, who appears to have held the earldom from about 1128 to about 1136, but whose relationship to Constantine is uncertain. Gillemichael died by 1136, when his successor, Donnchad (I). Gillemichael had a son, Aedh (Hugh), who became ancestor of the lords of Abernethy.