Warped cockroach

Warped cockroaches are found on the lower floor of the Lumbridge Catacombs, which can only be entered after completing The Blood Pact quest. Some low level mages may find this place an ideal place to train, because the cockroaches are low level, frequently drop runes, and have a very low max hit unlike their drone counterparts.

Warped cockroaches can also spawn in the Nemi Forest on Mazcab. These cockroaches, however, scale to the player's level.

Trivia

 * Although cockroaches are arthropods (and thus have external shells instead of internal skeletons), warped cockroaches drop bones.
 * Along with drones, warped cockroaches are the only attackable cockroaches not found in the Stronghold of Player Safety (there are a couple of drones near the entrance).

Warped cockroach