By Barbara Liston

ORLANDO, Fla (Reuters) - A Florida judge on Wednesday refused to dismiss a search-and-recovery organization's lawsuit against Casey Anthony, whose claims about her toddler's whereabouts in 2008 triggered a nationwide search.

Texas EquuSearch, a nonprofit group, was seeking to recoup more than $100,000 spent searching for her 2-year-old daughter Caylee based on Anthony's insistence that the child had been kidnapped by a nanny.

The lawsuit alleges fraud and unjust enrichment, claiming Anthony encouraged the organization to mount what became one of the largest and most expensive searches in its 11-year history despite knowing Caylee was dead.

"Resources were allocated here instead of to other families who had a missing person," Texas EquuSearch lawyer Marc Wites told Judge Lisa Munyon.

Caylee's remains were found in December 2008 in woods near the Anthony family home.

Casey Anthony, 25, was acquitted in July of killing her daughter. During her highly publicized murder trial, Anthony's lawyer said his client knew all along that Caylee had drowned in the family's backyard pool.

Anthony was convicted of lying to detectives about Caylee's whereabouts and ordered in September to reimburse law enforcement agencies for $217,500 worth of expenses stemming from the search for Caylee and the fictitious nanny.

Anthony's civil attorney Charles Greene told Judge Munyon on Wednesday that the nonprofit's fraud claim was based on a lie.

Greene said Texas EquuSearch founder Tim Miller had stated in news reports and to investigators that he did not believe in the summer of 2008 that Anthony was telling the truth.

But Texas EquuSearch lawyer Wites argued that Anthony never retracted her claim that Caylee was still alive, thus instigating the costly search.

Anthony did not attend the court hearing. She also faces a defamation suit filed by Zenaida Gonzalez, a woman who claims her life was destroyed when Anthony said someone by that name kidnapped Caylee.

(Editing by Colleen Jenkins and Cynthia Johnston)