| abstract | Species of Ceratozetes Berlese (Ceratozetidae) of Canada and Alaska are revised. Four new species, Ceratozetes watertonensis, C. borealis, C. oresbios and C. pacificus are proposed, C. gracilis cuspidatus Jacot is elevated to specific status and redescribed, and C. gracilis (Michael), C. peritus Grandjean, C. kananaskis Mitchell, C. virginicus (Banks), C. mediocris Berlese, and C. thienemanni Willmann are redescribed. Immatures of C. borealis and C. pacificus are described and those of C. peritus, C. kananaskis, C. mediocris, C. gracilis, C. virginicus and C. thienemanni are redescribed. Ceratozetes jeweli Rockett and Woodring is synonymized with C. virginicus. A key to species from Canada and Alaska is given. |