Because there are so many species and such diversity, the higher classification of weevils is changing all the time. Weevils are generally divided into two major divisions, the Orthoceri or primitive weevils, and the Gonatoceri or true weevils (Curculionidae). Primitive weevils are distinguished by having straight antennae, while true weevils have elbowed (geniculate) antennae. The elbow occurs at the end of the scape (first antennal segment) in true weevils, and the scape is usually much longer than the other antennal segments. Some exceptions occur. Nanophyini are primitive weevils (with very long trochanters) but have long scapes and geniculate antennae. From the true weevils, Gonipterinae and Ramphus have short scapes and little or no elbow.
Curculionidae: the head is extended into a long snout or rostrum bearing the mouth-parts; the antennae are clubbed (3-segmented club) and elbowed. Body is well sclerotized and hard, often covered with scales or hairs. males have a shorter rostrum. palps small and rigid, often concealed within mouth. Tarsi 5-5-5. Larvae are legless, with a sclerotized head capsule, stout mandibles.
Brentidae: body very elongate and narrow, sides nearly parallel; elytra striate with punctures. Prothorax and head more or less pear-shaped. Head with a forward-pointing beak that is very narrow and long in females and some males and broad in other males. Antennae often beadlike, weakly clubbed and not elbowed. body smooth, hairless and shiny.
Apionidae: generally recognizable by their pear-shaped body. Antennae not elbowed but distinctely clubbed. Snout is typically longer in females than males.
Attelabidae: markedly broad squarish bodied and have short snout. Antennae are not elbowed, weakly clubbed and inserted near the base of the rostrum. The head and prothorax are much narrower than the base of the elytra; neck often constricted and head prolonged. Some members of this family have extremely long neck and are called giraffe-necked weevil.