Ancylosis undulatella

Ancylosis undulatella, the sugarbeet crown borer moth or sugarbeet crown borer, is a species of snout moth in the genus Ancylosis. It was described by Clemens in 1860. It is found in North America, from Ontario and Michigan to Florida, west to California, north to Oregon and Idaho.

The wingspan is 16–18 mm. The forewings are narrow, light brown to greyish-brown with a reddish-brown to black band in the basal area. The hindwings are more than twice as broad as the forewings and greyish-brown with darker shading toward the outer margin. Adults are on wing from spring to fall in two generations per year.

The larvae feed on the leaves, leafstems and crowns of sugarbeets. The species overwinters in the pupal stage in the soil.