Where does “моллюсковый” come from?

моллюсковый (Russian) comes from Russian моллюск, from French mollusque, from New Latin Mollusca, from Latin molluscus, from Latin mollis, from Latin molduis, from Proto-Italic moldus, from Proto-Indo-European *ml̥dus — to soften, to melt.

моллюсковый (Russian): mollusc