Markelov has five full seasons of Formula 2/GP2 racing under his belt, taking nine victories 25 podium finishes.
Markelov stated that he and the team will drive in memory of Hubert, who won two F2 races earlier this year.
“First of all I want to give my best to the family of Anthoine," the Russian said. "This guy was not only a good driver, he was a great man who was happy all the time and always gave us a smile. He showed everyone his talent.
“Thanks to the team for trusting me in this situation and I’m going do my best for them. We are going to drive together in memory of Anthoine.
“I’m really happy I’ll be driving for BWT Arden for the rest of the championship. It’s a really nice opportunity to drive at my home grand prix again. I hope for a strong result and I’ll work hard to achieve it.”
BWT Arden Team Manager Kenny Kirwan added: “Following on from recent tragic events and our return to Sochi as a two-car team, we are proud and humbled to have Artem join us for the remaining races of the season.
“Artem is a proven race winner in this category and we very much relish the opportunity to work together and to continue where we left off with Anthoine, who we miss very dearly.”
Following this weekend's round in Sochi, the F1 feeder championship will return at the Yas Marina Circuit in Abu Dhabi for the final event of the 2019 season.
Bahrain International Circuit - Winter testing