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Northern Masked Chafer – Cyclocephala borealis

Northern Masked Chafer (Cyclocephala Borealis) Common Name: Northern Masked Chafer Latin Name: Cyclocephala Borealis Appearance:
  • Eggs are pearly white, oval, 1.7mm long and 1.2mm broad.
  • Northern masked chafers are 11 to 14 mm long and 6 to 7 mm broad as adults.
  • Their thoraxes and wing coverings are hairy, drab yellow-brown with darker patterns on the head and eyes.
  • The larvae eat plant roots and other items near the soil surface. The grownups do not consume food.
  • Pupae are 17mm long and 8mm broad and creamy-white at first before becoming reddish-brown when adults emerge.
Host plant: Northern masked chafer grubs prefer chilly season grass, especially if Japanese beetle grubs are repressed. However, both species attack the roots of field crops, including wheat, oats, and maize. The adults do not consume food. Territory: This species is native to North America, with specimens from Maine to California and as far south as Alabama. Damages caused by Northern Masked Chafer: Young larvae dig to the soil surface for plant roots; they also ingest organic matter in the soil and thatch. When there is enough moisture and food, the larvae develop quickly. As the earth’s temperature begins to decrease in the fall, the larvae begin to dig downwards to hibernate. Larvae may dig up to 12 inches, although most are only 3 to 6 inches deep, at least in the southern states. Grubs that survived the winter return to the top level of the soil to feed in late April and May. In late May and early June, the larvae descend slightly to pupate. Life history and habits: The northern and southern masked chafers have fairly similar life cycles and behaviors. Adult beetles typically emerge in mid-June and remain active until mid-July. Males emerge from the soil surface after dark before females. The southern masked chafer appears more active in the evening than its northern masked chafer counterpart. Males of the southern masked chafer emerge just before nightfall and scan the ground surface in search of unmated females. Mated females and males fly at night and are drawn to lights. Females dig four to six inches underground and lay 11 to 14 eggs. The larvae dig to the soil’s surface in quest of plant roots. As the earth’s temperature begins to decrease in the fall, the larvae begin to dig downwards to hibernate. Larvae may dig up to 12 inches, although most are only three to six inches deep, at least in the southern states. Grubs that survived the winter return to the soil surface to feed in late April and May. In late May and early June, the larvae descend slightly to pupate. The pupa develops within the old exoskeleton, which divides down the middle. The pupa matures in around 17 days.