A lepidopterist or aurelian is a person who specialises in the study of Lepidoptera, members of an order encompassing moths and butterflies. The term also includes hobbyists who are not formal scholars, who catch, collect, study, or simply observe lepidopterans. The field is formally known as Lepidopterology.

The Lepidoptera is an order of insects that includes moths and butterflies (both called lepidopterans). The Lepidoptera have, over millions of years, evolved a wide range of wing patterns and coloration ranging from drab moths akin to the related order Trichoptera, to the brightly colored and complex-patterned butterflies. Accordingly, this is the most recognized and popular of insect orders with many people involved in the observation, study, collection, rearing of, and commerce in these insects. A person who collects or studies this order is referred to as a lepidopterist.

https://en.wikipedia.org/wiki/Lepidoptera

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