Entiminae

There are over 12,000 described species in the Entiminae subfamily worldwide, distributed in over 1,370 genera,[1] which total nearly 14,000 by more recent counts.[2] Most tribes are represented in only one biogeographic region of the world. The current classification within the subfamily has been recognized as artificial rather than reflecting natural groups.[1]

Besides the shape of their broad and short rostrum, most entimines are easily recognized by the presence of a mandibular scar that appears when a deciduous process falls off the mandible, shortly after the emergence of the adult from the pupal stage.[3]

In general, entimines tend to feed on a broad range of plants (polyphagous), but there are instances of oligophagy. In general, the larvae feed externally on roots in the soil and adults feed on foliage.[1][3] They also show preference for habitat or substrate rather than plant specificity.[1]

Entimine weevils are primarily associated with angiosperms, but there are also species recorded from gymnosperms. They feed on monocotyledoneous and a broad range of dicotyledoneous plants, including members of the families Fabaceae, Malvaceae, Rutaceae, Solanaceae, and many more.[1]

The most commonly seen/known species are usually those associated with vegetation, where there is a trend to find more abundance and less diversity in cultivated areas, whereas forested or less disturbed areas tend to have more diversity and less abundance; there is a lot of diversity represented in the soil and on leaf litter, which is often overlooked.[4]

The most effective method for collecting entimines from vegetation would be using a beating sheet or by manual collecting; for soil entimines the best method would be leaf litter sifting.

Entimines may lay eggs loosely on the substrate, or in clusters glued onto the vegetation[5] and do not use their rostrum to prepare their oviposition site.[1] Over 50 species of entimines have been reported as parthenogenetic.[1]

The integument of entimines can be black, reddish, orange and even metallic in coloration. Many species of Entiminae are covered by scales arranged in a broad variety of patterns. Those scales bear three dimensional photonic crystals[6] within their lumen, which makes the scales iridescent.[1]

Many species are flightless, which usually can be seen externally: the elytral shoulders (outer anterior corners of the elytra) are reduced to absent in apterous and brachypterous forms and well-developed in species with well-developed wings.

Variation on development of elytral shoulders in entimine weevils.

The current tribal classification of Entiminae follows Alonso-Zarazaga & Lyal[7] for the most part, with a few updates by Bouchard et al.[8] The latest tribal addition is the Namaini Borovec & Meregalli.[9] Currently, there are 55 tribes recognized in the subfamily.

A key to identify tribes is presented by Legalov.[10]

• Donald E. Bright, Patrice Bouchard. The Insects and Arachnids of Canada, Part 25: Coleoptera. Curculionidae. Entiminae. Weevils of Canada and Alaska. Vol. 2. Ottawa, NRC Research Press, 2008. ISBN 0-660-19400-7.