(Reuters) - Money manager Calamos Investments said it has hired Gary Black, former chief executive of rival Janus Capital Group, as its global co-chief investment officer.

Black, who ran Janus from January 2006 through July 2009, will oversee portfolio management, research, trading and risk management at Calamos, the firm said in a statement on Thursday.

Calamos, based in Naperville, Illinois, will also be adding a long/short equity strategy by acquiring Black's current company, Black Capital LLC.

Nick P. Calamos, currently president and co-CIO, will step back from day-to-day responsibilities to pursue "personal interests," the firm said. Calamos is the nephew of founder and Chief Executive John Calamos Sr.

Calamos Investments, a unit of Calamos Asset Management, Inc., oversaw $33.6 billion as of July 31.

(Reporting by Aaron Pressman; Editing by Bernadette Baum)