The Tactires or Cranial Parasites were a species of parasitic insectoids.
The Tactires were insect-like, with a rounded head with several sets of antennae, a large thorax with four sets of legs, a long segmented abdomen with seven pairs of prolegs and large elytra, though no wings.
The Tactires lived on Callufrax Minor, (COMIC: The Forgotten) though they were apparently unknown to the Shadow Proclamation. (TV: The Stolen Earth) Es'Cartrss was the last member of the Tactire. He was able to escape to the Crucible and from there fled to the Doctor's TARDIS. Though he attempted to take over the Doctor's mind, with the help of the TARDIS, the Doctor was able to fight back and kill Es'Cartrss. (COMIC: The Forgotten)