RICE WEEVIL: Sitophilus oryzae, Curculionidae
ADULT: Small (1/8 to 3/16 in. long), dull reddish-brown to black beetles with round or irregular shaped pits on the thorax, and four yellow or reddish spots on the outside corners of the elytra. The head narrows and curves downward into a snout and comprises 1/3 the body length. Adults feign death when disturbed. Unlike some other grain weevils, the rice weevil can fly and does infest grains in the field.
EGG: Tiny, whitish, ovoid eggs deposited singly in corn kernels. Larvae emerge in 3 d.
LARVAE: The legless, grub-like, humpbacked, creamy white larvae have soft bodies and harder, brown heads. They complete development within the corn kernel in 18 d.
PUPA: They look like pale, immobile adults. Adults emerge from puparium inside corn kernels in 6 d.
GENERATION TIME: 26 to 32 d.
DAMAGE: Adults attack corn beginning in the hard dough stage in the field or post harvest. The adults chew a small hole in a corn kernel, deposit an egg and then seal the hole. Adults remain within the kernels for several days after emerging from the pupae.
CONTROL: Harvesting corn as soon as moisture content will allow helps to avoid damaging populations. There are no insecticides specifically labeled for rice weevil control in Florida corn.