Syllepte brunnescens is a moth in the family Crambidae. It was described by George Hampson in 1912. It is found in Brazil (Rio de Janeiro),[1] Panama and Mexico.[2]
The wingspan is about . The forewings are pale reddish brown, with a paler inner half. There are traces of a sinuous antemedial line and there is a faint dark spot in the middle of the cell, as well as a discoidal lunule. The postmedial line is indistinct. The hindwings are pale reddish brown with whitish basal and inner areas. There is a slight dark discoidal bar and an indistinct dark medial line.[3]