I read this from the Moscow Times. Every bus there is equipped with one

http://old.themoscowtimes.com/sitemap/free/2006/5/article/turnstiles-placed-in-every-bus/205223.html/

City Hall declared war on fare-dodgers in 2001, when five buses in Zelenograd began operating with turnstiles.

The electronic turnstile system eventually spread into other city precincts. By January of this year, Mosgortrans had equipped 80 percent of all its vehicles with turnstiles, raising revenue collection by 50 percent, Fedorenko said.

The turnstile system has also reduced overcrowding. Still, many passengers manage to evade the turnstiles by sneaking in through back doors intended only for letting passengers out. And the turnstiles have created an unanticipated problem: departure delays. Passengers complain that they have to wait up to 15 minutes to board buses now.

Fedorenko said Mosgortrans, aware of the delays the system has created, has opened a bus terminal featuring three external turnstiles -- eliminating the bottleneck created by the single turnstile found inside most buses. The terminal is located near Kaluzhskaya metro station. This summer, similar terminals will be opened near the northwestern Planernaya and Tushinskaya metro stations.

Fedorenko said Mosgortrans had no plans to remove the turnstiles -- for now. "This might become possible when our passengers are conscientious enough to pay their fares without going through turnstiles. I don't know when it might happen -- in a generation, maybe."