Sentence:  (And we'll never find out whether the last thought to pass through the mind of the captain of the "Thresher" was, "It's <WSD>squamous</WSD> and rugose," or simply, "It's <WSD>squamous</WSD>!") 
Meaning of the word marked with <WSD> tags:  Covered with, made of, or resembling scales; scaly.