Grain-weevil
Guides
Caulophilus oryzae
Broad-nosed Grain Weevil
Caulophilus oryzae is a stored product pest in the family Curculionidae, commonly known as the broad-nosed grain weevil. It serves as an alternative host for the ectoparasitic wasp Cephalonomia hyalinipennis. The species is found in stored grain environments and has been documented in the Galápagos Islands, North America, and the Canary Islands.
Sitophilus
Grain Weevils
Sitophilus is a genus of weevils comprising approximately 14 species, several of which are major pests of stored grain, nuts, and seeds worldwide. The genus includes three of the most economically significant stored-product insects: the rice weevil (S. oryzae), wheat weevil (S. granarius), and maize weevil (S. zeamais). Adults are characterized by a pronounced rostrum and elbowed antennae. Females bore into individual grains to deposit single eggs, sealing the hole with secretion; larvae develop entirely within the grain, often leaving it hollow upon emergence. Many species maintain intracellular symbiotic relationships with γ-Proteobacteria that supplement their nutrient-poor cereal diet.
Sitophilus granarius
granary weevil, wheat weevil, grain weevil
Sitophilus granarius is a cosmopolitan pest of stored cereals, commonly known as the granary weevil or wheat weevil. Adults are flightless and infest raw grains including wheat, barley, and oats, causing significant quantitative and qualitative losses in storage facilities. The species is distinguished from similar storage weevils by its inability to fly and its preference for cooler, drier conditions. Larvae develop endophytically inside grain kernels, completing their entire immature life cycle within a single seed.