A tiny endangered butterfly could stop President Donald Trump from building his beloved border wall.

A lawsuit has been filed by the Center for Biological Diversity, environmental groups and the State of California against the U.S. Department of Homeland Security.

It outlines that the Quino checkerspot butterfly, Riverside fairy shrimp and the Pacific pocket mouse will be threatened if the border wall is built.

The butterfly, which is native to southern California and Northern Mexico, is already on the endangered species list.

The lawsuit contends that the Department of Homeland Security does not have the ability to waive environmental laws requiring review before building the wall.

The suit seeks a ruling that a border wall with Mexico must go through normal environmental reviews, which could block construction or at least cause major delays.

The endangered Quino checkerspot butterfly would not be able to migrate over the proposed border wall

The Pacific pocket mouse was once thought to be extinct, it is on the endangered species list

Prototypes for the border wall as seen from Tijuana. The lawsuit says the wall would endanger several species

The challengers contend that authority to waive the environmental reviews falls under a 2005 law which has expired.

'The Trump administration can't use an expired waiver to bypass crucial environmental protections to build these destructive projects,' Brian Segee, a senior attorney at CBD,told San Diego TV station KGTV.

'It's time to stop Trump's hateful bombast and his executive overreach here in San Diego before it goes any further. The law and the Constitution are firmly on our side, and we think the judge will agree.'

The DHS is arguing that it is within its right to issue the waivers, citing a 1996 immigration law.

The case was set to be heard on Friday in San Diego by US District Judge Gonzalo Curiel.

US District Judge Gonzalo Curiel, left, who heard a case against Trump University will hear the case. Brian Segee, right, a lawyer for the Center for Biological Diversity, spoke to reporters outside the courthouse on Friday

President Trump, pictured in the Oval Office on Friday, has called the judge biased before, during a 2016 case against Trump University

Curiel came to national attention in 2016 when he was presiding over one of the cases against Trump University.

Trump said that he was biased because of his 'Mexican Heritage' and Trump's stance on the border.

At the time, he told CNN: 'We are building a wall. He's a Mexican. We're building a wall between here and Mexico.'

Now Curiel will be hearing a case about the wall. On Friday he heard two-and-a-half hours of arguments and said that he was leaning toward deciding he has jurisdiction in a lawsuit that alleges the Trump administration overreached in waiving laws that require environmental and other reviews.

The administration argues he doesn't have jurisdiction.

Curiel asked the administration and wall opponents to file additional briefings by the end of Tuesday.