The UCR Entomology Research Museum is the insect collection of the Department of Entomology of the University of California, Riverside. It contains approximately 4 million total insect specimens, over 3 million of which are pinned, roughly 400,000 mounted on slides, the remainder preserved in ethanol (including most of the non-insect arthropods, and some snails). Of the ~4 million curated holdings, approximately 75% of are identified to genus level or better. An estimated 25% of the entire collection are Hymenoptera, 21% are Coleoptera, 18% Diptera, and 18% Lepidoptera.