protracheata

from The Century Dictionary.

• In Gegenbaur's system, one of three prime series into which all arthropods are divided (the others being Branchiata, or Crustacea in a wide sense, and Tracheata, or insects in the widest sense), established for the reception of the single genus Peripatus: thus conterminous with Malacopoda, Onychophora, and Peripatidea.

from the GNU version of the Collaborative International Dictionary of English.

• noun plural (Zoöl.) Same as malacopoda.