absence of ocelloids and fontanelle, antennae with 22–27 articles, pronotum distinctly narrower than head, tarsi pentamerous (sometimes cryptically), fourth sternite with sole sternal gland, forewing scale overlapping hind-wing scale, humeral
margin of scale flat, imago-worker mandibles with three marginal teeth (left side) and subsidiary tooth between apical and first
marginal teeth (right side).