thumb|right|[[Cionus hortulanus]]

The Curculionidae are a family of weevils, commonly called snout beetles or true weevils. They are one of the largest animal families with 6,800 genera and 83,000 species described worldwide.<!-- They are surpassed only by the Ichneumonidae (Hymenoptera), with over 60,000 species, and the Staphylinidae (Coleoptera), with 58,000 species. --> They are the sister group to the family Brentidae.

They include the bark beetles as the subfamily Scolytinae, which are modified in shape in accordance with their wood-boring lifestyle. They do not much resemble other weevils, so they were traditionally considered a distinct family, Scolytidae. The family also includes the ambrosia beetles, of which the present-day subfamily Platypodinae was formerly considered the distinct family Platypodidae.

Description

Adult Curculionidae can be recognised by the well-developed, downwards-curved snout (rostrum) possessed by many species, though the rostrum is sometimes short (e.g. Entiminae). They have elbowed antennae that end in clubs, and the first antennal segment often fits into a groove in the side of the rostrum.

alt=Pissodes_pini_(Linnaeus,_1758)|thumb|[[Pissodes pini]]

Behavior

When disturbed, adult curculionids often play dead by lying motionless on their backs.

Phylogeny and systematics

The phylogeny of the group is complex; with so many species, a spirited debate exists about the relationships between subfamilies and genera. A 1997 analysis attempted to construct a phylogeny based mainly on larval characteristics.<!-- Two recent (and widely different) systematic schemes: Oberprieler et al. (2007), Bouchard et al. (2011) -->

Recent work on the phylogenetic relationships in weevils mentions the two subfamily groups Adelognatha (short-nosed weevils, subfamily Entiminae) and Phanerognatha (long-nosed weevils, subfamilies of Curculionidae other than Entiminae) for the species of Curculionidae.

Almost two dozen subfamilies are recognized by some authors even when merging those that are certainly invalid. Others, however, recognize a lesser number – the only subfamilies that are almost universally considered valid are the Baridinae, Cossoninae, Curculioninae, Cyclominae, Entiminae, Molytinae, Platypodinae, and Scolytinae. The various proposed taxonomic schemes typically recognize as many additional subfamilies again, but little agreement is seen between authorities about which. In particular, the delimitation of the Molytinae has proven difficult.

The timeline for current and extant weevil speciation and diversification is consistent with the radiation of gymnosperms during the Mesozoic period.

thumb|160px|Curculio, scarabeiform larva

The subfamilies considered valid by at least some authors today:

  • Bagoinae (sometimes in Molytinae)
  • Baridinae
  • Brachycerinae (disputed; sometimes placed at family level)
  • Ceutorhynchinae (sometimes in Baridinae)
  • Conoderinae (sometimes in Baridinae)
  • Cossoninae
  • Cryptorhynchinae (sometimes in Curculioninae)thumb|Cionus tuberculosus ([[Curculioninae)]]
  • Acalles
  • Curculioninae – flower weevils, acorn and nut weevils

thumb|Curculio nucum, a brown nut-weevil

  • Cyclominae
  • Dryophthorinae (sometimes placed at family level)
  • Entiminae – broad-nosed weevils
  • Hyperinae (sometimes in Molytinae)
  • Lixinae (sometimes in Molytinae)
  • Mesoptiliinae (sometimes in Molytinae)
  • Molytinae
  • Orobitidinae - 2 genera:
  • Orobitis
  • Parorobitis
  • Platypodinae – typical ambrosia beetles, "higher" Curculionidae