univalve vs univalved

univalve

adj
  • consisting of a single valve or piece, used to refer to a shell. 

  • having one valve; typically used to refer to mollusks, notably slugs and snails. 

noun
  • A univalve mollusk or its shell. 

univalved

adj
  • Having one valve. 

How often have the words univalve and univalved occurred in a corpus of books? (source: Google Ngram Viewer )