Plural form of apterum; insects or organisms without wings, or the wingless forms of certain insects like lice and fleas.
From Greek a- (without) + pteron (wing). This is the plural of apterum, used in entomology to describe wingless insects or the wingless stages of insects that can be winged.
Lice and fleas are aptera—their ancestors had wings but lost them because why fly when you can ride your host like a living bus?
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