On Saturday, police said officers were travelling to London to talk to 38-year-old man Graime Morris, who was being held in custody in London in connection with the incident.
He was brought back to Scotland and arrested on Sunday night. A report is being sent to the procurator fiscal and he is due to appear at Ayr Sheriff Court.
A post-mortem examination is expected to take place to establish the exact cause of Mrs Morris' death.