Fenusa Pusilla is a species of sawfly that belongs to the family Tenthredinidae. This insect is commonly found in North America, where it feeds on the leaves of a variety of deciduous trees, including maples, oaks, and poplars. Other names that this species might be referred to as include the maple leafcutter, maple sawfly, and poplar sawfly. While these names may differ slightly, they all refer to the same insect. This species plays an important role in the ecosystem as both a food source for other animals and a natural predator of certain pests.