Dec 18 (reuters) - forbes energy services ltd ::forbes energy services announces combination of forbes energy services with us onshore oilfield services business of superior energy.forbes energy services- superior energy has agreed that newco will list on nasdaq.forbes energy services ltd - co's common stock holders will receive 50.1% of voting class a common stock of combined co.forbes energy services ltd - combined co expects to generate annualized run-rate cost synergies of about $23 million within a year after closing transaction.forbes energy services ltd - transaction has been unanimously approved by a special committee of co's directors & by boards of co & superior energy.forbes energy services ltd - newco's class a stock will initially trade in over-the-counter market.