HOUSTON (Reuters) - Siemens Energy Inc has filed a lawsuit in a Texas court against Citgo Petroleum's parent, PDV Holding, seeking to recoup about $200 million from a promissory note defaulted by Venezuela, according to a court document seen on Wednesday.

Creditors that are part of an auction of Citgo parent's shares in a Delaware court to pay billions of dollars for expropriations and debt defaults in Venezuela have begun turning to other U.S. courts to enforce their claims, a strategy to gain priority when the auction's proceeds are paid.

The auction's second bidding round was completed last month with the selection of an affiliate of Elliott Investment Management as the winner. If the judge ratifies the $7.3 billion offer, there might not be enough money to pay more than a handful of the $21 billion in creditor claims before the court.

Citgo and PDV Holding are U.S. subsidiaries of Caracas-headquartered state oil firm PDVSA. The dispute between PDVSA and Siemens comes from a transaction under which engineering firm Dresser-Rand Company, acquired by Siemens Energy, was entitled to receive some $166 million pursuant to a promissory note.

"SEI obtained a judgment against PDVSA from the Southern District of New York and now seeks to hold PDV Holding liable as PDVSA's alter ego for the full amount of the judgment, which now exceeds $200 million," the document filed by Siemens said.

Gramercy Distressed Opportunity Fund and two related companies have filed similar lawsuits in Texas and New York courts this year, threatening to derail the auction in Delaware, which is scheduled to be completed in the coming months.

A court officer appointed to oversee the auction has requested U.S. Judge Leonard Stark block the creditors from resorting to other courts to pursue the same assets. His decision is pending.