The suspect in Long Island’s infamous Gilgo Beach serial killings has lost his bid to separate into multiple trials the sprawling case involving seven brutal killings spanning decades.

New York State Supreme Court Justice Timothy Mazzei ruled Tuesday that the trial against Rex Heuermann, a Manhattan architect who lived on Long Island, would move forward as a single trial.

Suffolk County District Attorney Ray Tierney said he was not suprised by the ruling. He spoke to reporters, flanked by Heuermann's estranged wife Asa Ellerup and his daughter, Victoria.

Lawyers for Heuermann had argued in court filings that there was no “unique and consistent modus operandi” common to all the murders, as prosecutors claimed. They said the case should be broken up into as many as five trials because the killings involved different time frames, torture and mutilation techniques, and dump sites for the bodies.

Heuermann's lawyers also contended that jurors would struggle with the “volume and complexity” of the evidence in the case if all seven killings were tried together. They argued the 62-year-old Massapequa resident risked being improperly convicted by the “cumulative effect” of the evidence against him.

Prosecutors, in their own filings, dismissed variances in the killing styles as “minor inconsistencies” that showed Heuermann was either “refining and tinkering” with his methods, or intentionally trying to “confuse or mislead law enforcement” -- an argument that the defense rejected as “untenable.

On other matters, Mazzei on Tuesday turned down defense lawyers’ second attempt to toss out some of the DNA evidence that prosecutors say overwhelmingly implicates Heuermann.

Heuermann was arrested more than two years ago and has been charged in the deaths of seven women in a series of killings that prosecutors say stretched back at least to 1993. He has pleaded not guilty. His next court appearance is in January.