BossHog Tusks can be obtained from BossHogs of course, either by killing them or taming them, feeding them and harvesting from them after they have become your Pets.
BossHogs live in Savannah-biomes and can spawn on Savannah Grass, but also in some Canyon areas like around oases during the day and night.
They are aggressive and will attack player-characters who get too close to them.
Even though they clearly seem to be related with Pigsies, BossHog-Pets will not give Pigsy Droppings as a pet-harvest, but they can drop Leather and both Year of the Pig Lantern crafting recipes and Plum Blossom recipes.
BossHog Tusk is a crafting ingredient needed for crafting-recipes like Advanced Health Potions.
This material cannot be put into your quickbar and cannot be placed into the world. It also cannot be displayed on any display containers.