San Francisco lepidopterist Liam O'Brien shares observations and illustrations from the field.


Journal of A Robberfly in Mexico


Bay Area lepidopterist Liam O’Brien spent the 2019 City Nature Challenge surveying the biodiversity of Mazatlan at the invitation of Mexican naturalists.

Sex and the Single Butterfly


What most of us call “butterflies” are in fact just the fleeting last life stage of a creature with only one remaining purpose.