The 22-year-old is also being questioned over burglary and theft following the incident in which the woman died from multiple stab wounds.
Jill Hibberd was found dead at her home on Roy Kilner Road in Barnsley at 7.45am last Thursday, May 31.
A 40-year-old man from Wombwell was already charged with murder, burglary and theft of a vehicle.
A red Audi TT taken from Mrs Hibberd’s driveway the night before has now been recovered in the West Yorkshire area. South Yorkshire Police are still keen to speak to anyone who may have seen the vehicle prior to its recovery.
DCI Jude Ashmore investigating said: “I want to offer my sincerest thanks to those who have been in touch with us, and while we are now in possession of the vehicle and various forensic analysis will be undertaken, I am still appealing to anyone who believes they may have seen the car, on specific dates and times.
“Did you see the car, registration number YM17 SYJ, taken from the scene of the crime? The specific details, while they may seem insignificant, could be vital to the investigation and I would urge anyone who believes they could assist to make contact with us via our incident room on 01709 443510.
“Alternatively, please call 101 or anonymously make contact with Crimestoppers on 0800 555111, quoting incident number 141 of May 31.”