Russian aircraft carried out strikes in support of their Syrian ally, the so-called Syrian Observatory for Human Rights said, AFP reported.
The clashes broke out in two separate areas of the vast desert that separates the Orontes valley in the west from the Euphrates valley in the east.
The government side lost 41 dead, the Daesh militants 49, the Britain-based war monitor said.
Mobile Daesh units have remained active in the Syrian Desert, known in Arabic as the Badia, since the militants lost the last shred of its self-proclaimed caliphate in March last year.