Cave millipedes of the United States. XVI. Two new species from Oregon Caves National Monument, Oregon (Chordeumatida, Conotylidae and Caseyidae).

Two new species of millipedes are described from Oregon Caves National Monument, Josephine County, Oregon, USA: Taiyutyla caseophila, n. sp. (Conotylidae), a troglophile; and Opiona catorycha, n. sp. (Caseyidae), a troglobiont found in at least one other cave in the region. We also provide a brief discussion of the invertebrate biodiversity of Oregon Cave.