Entomologists who capture, collect, and conduct research on living things in the Lepidoptera class, such as butterflies and moths, are called lepidopterists.
The general name given to people who are interested in creatures categorized under the name lepidoptera (butterflies, moths, beetles, lepidoptera, some insects). To take care of here generally means to collect.
Lepidopterology is a branch of entomology concerning the scientific study of moths and the two superfamilies of butterflies. Someone who studies in this field is a lepidopterist or, archaically, an aurelian.
One of the most famous Lepidopterists is Vladimir Nabokov, the author of Lolita.
Turkish professor Doctor Ahmet Ömer Koçak, who found and named around five hundred species, is one of the world-renowned professors in this field.