Quill, which worked on the account for three years, was not invited to repitch for the business.
Penrose partner Claire Burston is briefed to increase the fund manager's profile in the UK, particularly among institutional and private clients.
Formerly chief financial officer of ABN Amro's wholesale client division, Russell replaces Huibert Boumeest as chief executive in January.
She will oversee a new business structure made up of five regional client business units.
The business units will develop products focusing particularly on the mid-market sector.