FIGURES 4–7. Opiona graeningi, n in Cave millipeds of the United States. XI. Opiona graeningi, n. sp., a troglomorphic caseyid milliped from Siskiyou County, California, with comments on the genus Opiona Chamberlin 1951 (Diplopoda, Chordeumatida, Caseyidae)

FIGURES 4–7. Opiona graeningi, n. sp. Fig. 4, tarsus of leg 1, anterior view. Fig. 5, legpairs 2 and 3, anterior view, see text for labels. Fig. 6, legpair 9, anterior view. Fig. 7, coxae of legpair 10, anterior view.