Global securities head Ryan leaves Credit Suisse

NEW YORK, April 10 (Reuters) - Mike Ryan, global head of stocks and bonds at Credit Suisse Group (CSGN.VX) resigned on Thursday, less than a year after he joined the firm, according to an internal memo obtained by Reuters, after a trading scandal rocked the bank.

The memo did not give a reason for Ryan's departure, but Investment Bank CEO Paul Calello said in a memo that Ryan had faced "very challenging markets" over the past months.

Credit Suisse said in mid-February that it had written down some $2.85 billion of bad asset-backed investments and suspended some traders after finding pricing errors on its books. The bank said last month that it could report its first quarterly loss in five years.

Ryan came to Credit Suisse from Goldman Sachs Group Inc (GS.N) where he had served as global co-head of equity sales and trading. Gael de Boissard, Tony Ehinger, Steve Kantor and Jonathan McHardy will jointly replace Ryan as co-heads of the global security division, the memo said.

Yesterday, JPMorgan Chase & Co (JPM.N) cut its 2008 earnings estimates for Credit Suisse to 6.07 Swiss francs ($6.01) per share from 7.25 Swiss francs.

Credit Suisse shares have fallen almost 20 percent so far this year and, as of this afternoon, were trading around 54.70 Swiss francs per share. (Reporting by Steven Bertoni; Editing by Andre Grenon)