the idea that one species (= set of animals with the same characteristics that can breed from each other), especially human beings, is more important and should have more rights than another

They call the assertion of human superiority over other animals "speciesism". 他们把宣称人类优于其他动物的行为称为“物种歧视”。

It is sheer speciesism that very few humans campaign to Save Our Slugs. 很少有人类开展拯救鼻涕虫的活动，这纯粹是物种歧视。