Locomotion in the terrestrial planarian Artioposthia triangulata (Dendy)

The locomotion of Artioposthia triangulata was studied in the laboratory by comparing the relative positions of a series of markers placed on the dorsal side of the body as specimens moved over a variety of types of surfaces. They were found to glide over damp surfaces or to use retrograde peristaltic waves over dry surfaces. These waves passed down the body as three or four muscular bulges with the body held slightly off the ground between each bulge. The specimens travelled faster over dry surfaces than damp ones. Cilia were seen over the entire body surface and were longer and more numerous in the head region and at the sides of the body. Using mark and recapture the distance travelled over 30 days was found for 100 marked specimens released back into the allotment. The greatest distance from the point of release at which a specimen was recaptured after 30 days was 17 m. The speed of locomotion is compared with published data for four other species of terrestrial planarians.