Weevils are beetles belonging to the superfamily Curculionoidea, known for their elongated snouts. They are usually small, less than 6 mm in length, and herbivorous. Approximately 97,000 species of weevils are known. They belong to several families, with most of them in the family Curculionidae. It also includes bark beetles, which while morphologically dissimilar to other weevils in lacking the distinctive snout, is a subfamily of Curculionidae. Some other beetles, although not closely related, bear the name "weevil", such as the biscuit weevil, which belongs to the family Ptinidae.
Anthonomus is a genus of weevils. This genus includes major agricultural pests such as the boll weevil, strawberry blossom weevil, and pepper weevil, as well as promising biological pest control agents such as Anthonomus santacruzi.
Brentidae is a cosmopolitan family of primarily xylophagous beetles also known as straight-snouted weevils. The concept of this family has been expanded with the inclusion of three groups formerly placed in the Curculionidae; the subfamilies Apioninae, Cyladinae, and Nanophyinae, as well as the Ithycerinae, previously considered a separate family. They are most diverse in the tropics, but occur throughout the temperate regions of the world. They are among the families of weevils that have non-elbowed antennae, and tend to be elongate and flattened, though there are numerous exceptions.
Curculio is a genus of weevils belonging the family Curculionidae and subfamily Curculioninae. Members of the genus are commonly referred to as acorn weevils or nut weevils as they infest the seeds of trees such as oaks and hickories. The adult female weevil bores a tiny hole in the immature nut to lay her eggs, which then hatch into legless grubs. In autumn, the grubs bore holes through the shells from the inside to emerge into the soil where they may live for a year or two before maturing into adults.
The palm weevil Rhynchophorus ferrugineus is one of two species of snout beetle known as the red palm weevil, Asian palm weevil or sago palm weevil. The adult beetles are relatively large, ranging between 2 and 4 centimetres long, and are usually a rusty red colour—but many colour variants exist and have often been classified as different species. Weevil larvae can excavate holes in the trunks of palm trees up to 1 metre (3.3 ft) long, thereby weakening and eventually killing the host plant. As a result, the weevil is considered a major pest in palm plantations, including the coconut palm, date palm and oil palm.
Otiorhynchus is a large genus of weevils in the family Curculionidae. Many species of the genus, particularly the black vine weevil and the strawberry root weevil, are important pests, both as larvae and as adults. Larvae feed on plant roots. Adults are flightless with fused elytra and feed at night on plant foliage. In many species of the genus at least some races are polyploid and parthenogenetic, while the rest of the races and species are diploid and bisexual. Otiorhynchus weevils, particularly O. scaber, have been a popular subject for studies of the evolution of parthenogenesis. The genus is native to the Palearctic region. However, sixteen species were inadvertently introduced to North America and have become widespread there.
Sitona is a large genus of weevils in the family Curculionidae native to the Nearctic and Palaearctic regions. Over 100 species have been described. Sitona is easily distinguished from related genera by flat, recumbent scales on the mandibles, by the absence of an oval scar on the mandibles, by short and broad rostrum with a deep, longitudinal, median groove, and by dense scales on the body.
Euops is a genus of the leaf-rolling weevils containing more than 300 species. It is spread over most tropical and subtropical regions but is missing from America. The centre of its radiation is New Guinea and Australia where it is the only representative of the subfamily Attelabinae.
Trigonopterus oblongus is a weevil found in Papua. It was notable as the first known instance of a biological screw joint. The weevils are just 4 millimetres (0.16 in) long and can fold their legs below their body. The biological screw joint is just 0.5 millimetres (0.020 in) in size. This discovery was made by Alexander Riedel of the State Museum of Natural History Karlsruhe and by Thomas van de Kamp of the Karlsruhe Institute of Technology.
Rhynchophorus, or common name palm weevils, is a genus of beetles in the weevil family, Curculionidae. Palm weevils are major pests of various trees in the family Arecaceae throughout the tropics including: coconut, Areca catechu, species of the genus Phoenix, and Metroxylon sagu. Two species are invasive pests outside their native ranges, Rhynchophorus ferrugineus and Rhynchophorus palmarum.
Ithystenus is a genus of straight-snouted weevils belonging to the family Brentidae. Species of this genus can be found in Papua New Guinea
Cleonis is a genus of cylindrical weevils in the beetle family Curculionidae. There are at least 120 described species in Cleonis.
Hypera is a genus of clover and alfalfa weevils in the beetle family Curculionidae. There are at least 280 described species in Hypera.
Rhyssomatus is a genus of true weevils in the beetle family Curculionidae. There are at least 180 described species in Rhyssomatus.
Steremnius is a genus of true weevils in the beetle family Curculionidae. There are at least four described species in Steremnius.
Rhyncolus is a genus of true weevils in the beetle family Curculionidae. There are at least 140 described species in Rhyncolus.
Tanymecus is a genus of broad-nosed weevils in the beetle family Curculionidae. There are at least 100 described species in Tanymecus.
Neoptochus is a genus of oriental broad-nosed weevils in the beetle family Curculionidae. There is at least one described species in Neoptochus, N. adspersus.
Trigonopterus chewbacca is a species of flightless weevil in the genus Trigonopterus from Papua New Guinea.
Barystethus is a genus of the true weevil family.
