A further development of Nona, 120mm 2S31 Vena is a multi-purpose amphibious SP tracked artillery
2S31 Vena By Russia system, combining capabilities of a gun, a howitzer and a mortar. It is designed for direct fire support on the battlefield. Vena fires the same range of ammunition Nona does.

High accuracy is ensured by an automated laying system featuring a computer to generate fire settings. In addition, it mounts an automatic survey and orientation system and a day/night optronic surveillance and target designation system. Mounting Vena on BMP-3’s chassis provides it with enhanced mobility.
the Russian Motovilikha Plants Corporation fielded the latest of its Nona family, the 2S31 Vena, an automated self propelled mortar, with a longer barrel, (Russian 120mm 2A80) also firing the Gran laser-guided bomb against point targets to 13km range. AMOS II mobile mortar system.