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# 42: Weevils


Litinsects #42: Weevils

We are back on insects! Who has heard of weevils before? Weevils are a type of beetle known for their long “nose” or ROSTRUM. They are also called snout beetles and, believe it or not, some of those snouts are pretty cute.

“Weevil” can mean either PRIMITIVE WEEVILS, which have straight antennae, or TRUE WEEVILS, which have elbowed antennae. Primitive weevils describe a number of different families whereas true weevils comprise a single family (which is a level of classification above genus).

True weevils are considered one of the most SPECIOSE (aka species-rich) families of animals on earth. Disclaimer: of course we can only say this based on our current knowledge and not with absolute certainty because there are countless insect species yet to be discovered... but there are currently around 45,000 described species of true weevils! Let me give you some perspective on that number: if you added up all the living species of birds, mammals, reptiles, and amphibians you would get only about 2/3 of the total number of species within this ONE FAMILY of beetles.

  • Weevils are herbivores and many species are considered pests. Maize, rice, and wheat weevils for example attack stored products while others attack living crops
  • The BOLL WEEVIL is one of the most destructive pests in US history, having had devastating effects on cotton farmers in the past. Thanks to the US Department of Agriculture’s eradication program, many areas have been eradicated while reducing the use of pesticides
  • There is one true weevil species that exhibits EUSOCIALITY (which, you might remember from my eusociality post, is pretty rare outside of ants, bees, wasps, and termites). These weevils live in colonies with a single reproductive female and farm fungi (similar to the leaf cutter ants from a few posts ago)!
  • One of the most bizarre (primitive) weevils is the GIRAFFE WEEVIL, found only in Madagascar. If you’ve never heard of it before, do yourself a favor and go google it
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