By Mary Ellen Podmolik | Morton’s Restaurant Group, Inc. announced that Thomas Baldwin, its chairman, chief executive officer and president, has resigned from the company after 21 years there.

Morton’s said it appointed Christopher Artinian, 40, as its chief executive officer, president and as a director. Artinian joined the company in 1995 and most recently served as vice president of Eastern operations for Morton’s of Chicago Inc., a subsidiary.

No reason was given for the departure and the company declined to discuss his exit beyond a prepared press release. No reason was given for the departure and the company declined to discuss his exit beyond a prepared press release.

“Tom Baldwin made significant contributions to the company over the last 21 years as a member of our management team and we truly appreciate everything he has done for Morton’s,” Roger Drake, a Morton’s senior vice president, said in a press release.

In a Securities and Exchange Commissoin filing, the company said its board accepted Baldwin’s resignation Feb. 1, at which time it elected Artinian to the role of president and chief executive.

Efforts to reach Baldwin were unsuccessful.

In November, the company reported a three-month net loss of $3.3 million, or 21 cents a share, compared to net loss of $63.7 million, or $.02 a share, the comparable period in 2008. Revenues decreased 12.2 percent during the quarter.