Leaf-clipping-behavior
Guides
Symmerista
Symmerista is a genus of prominent moths (family Notodontidae) erected by Jacob Hübner in 1821. The genus contains at least nine described species distributed primarily in North America, with several species described from Central America. Larvae are notable for a distinctive leaf-clipping behavior where they sever petioles after feeding and apply red saliva to the cut surface, a trait that has been experimentally demonstrated to introduce salivary constituents into the plant's vascular system to suppress defense responses in nearby leaves.
Symmerista leucitys
orange-humped mapleworm moth, orange-humped mapleworm
Symmerista leucitys is a notodontid moth commonly known as the orange-humped mapleworm moth. The species is a univoltine specialist defoliator of sugar maple, with a single generation per year. Larvae exhibit distinctive leaf-clipping behavior, severing petioles after feeding and applying red saliva containing pigments from the anterior labial glands to the petiole stub. This saliva travels rapidly into the petiole xylem and is hypothesized to suppress plant defense responses in nearby leaves. During outbreak years, clipped leaves can comprise over 80% of greenfall losses in early October.