Sentence:  Let us not try to key them out at this stage of the game , and let us just call them Bombus ; there must be several dozen species in the <WSD>United</WSD> States alone . 
Meaning of the word marked with <WSD> tags:  North American republic containing 50 states - 48 conterminous states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776