The Subphylum Pentastomida is a group of parasitic organisms that primarily infest the respiratory tracts of vertebrates. These organisms have several synonyms that relate to various aspects either about their morphology or their biochemistry. Some of the synonyms of the Subphylum Pentastomida include Arthrogastrida, Rhinocryptida, Linguatulida, and Porocephalida. These synonyms are useful to understand the diversity and evolutionary history of these unusual organisms. While they are not a well-known group of organisms, learning about their different names and classifications helps researchers better understand their biology. Overall, understanding synonyms for the Subphylum Pentastomida is key to better understanding these fascinating creatures.