Key to species of Oskoron
1a. Chelicerae shorter than or only slightly longer than body; metapeltidium with two setae; Oregon, Washington .................................................................................................... brevichelis n. sp .
1b. Chelicerae distinctly longer than body; metapeltidium with single row of four to eight (ten) setae..................... 2.
2a. Ocularium armed with very prominent curved, black setae on acute tubercles; metapeltidium with row of at least eight setae; penis of male distally expanded; California .................................................... spinosus (Banks) .
2b. Ocularium with few setae on low tubercles, metapeltidium with six or fewer setae; penis of male not distally expanded; Washington ................................................................................... crawfordi n. sp.