First Mug Shot of Robert Durst After Being Sent to State Prison

Robert Durst is looking worse for wear since being shipped off to a California prison facility -- and based on how he's looking here ... he ain't gonna be in a cell for a long while.

The recently-convicted NY real estate scion posed for his first mug shot Thursday while apparently in a hospital bed of some sort. In the photo, obtained by TMZ, you can see Durst with his face mask pulled down to his chin ... and him solemnly looking into the camera.

Obviously, he appears quite frail and ill ... as he has been for some time now, but this is especially bad. Remember, the guy is recovering from a COVID-19 diagnosis that came down some 2 weeks ago, which saw him have to be relegated to a ventilator for oxygen.

As for where Durst is now ... he's been transferred from the L.A. County jail system to the California Health Care Facility in Stockton -- which is part of the CA state prison system, and which takes in and attends to their most health-impaired inmates.

Durst was taken to Stockton on Wednesday.

Durst was found guilty of murdering his friend, Susan Berman, just a few weeks ago -- and was handed a life sentence as a result.

Berman's killing is believed to have been tied to the 1982 disappearance of his then-wife, Kathy, whom many believed was also offed by Durst ... albeit, he was never officially implicated, until last week.

It appears prosecutors think they finally have the goods to pin him to the crime -- 'cause they filed charges against him after all these years ... so that case will play out in the future.