Locative case marker of Contemporary Korean is often realized as /-i/ or /-Щ/ in Chungnam and Jeonbuk dialects. They occur after the nouns ended with a consonant: in Chungnam dialect /-i/ occurs regardless of final consonants of noun while in Jeonbuk dialect /-i/ occurs after [-grave] consonants and /-Щ/ occurs after [+grave] consonants. They are considered to originate from the same marker /-Щi/ which would be called `special locative case marker`. Case marker /-Щi/ has experienced the same change of monophthongization as word-final diphthong /Щi/. The aspect of monophthongization of the latter is similar phonologically and regionally to the former.