Regeneration in a Neotropical land planarian (Platyhelminthes, Tricladida)

Abstract

Planarians are known for their ability to regenerate missing body parts. However, little is known about the regeneration ability of land planarians, especially regarding Neotropical species. Herein, we investigated the regeneration in the Neotropical land planarian Luteostriata abundans. Specimens were cut in two at different points along the body and monitored for 50 days. Larger and anterior pieces survived more than smaller posterior pieces. Anterior pieces that retained the pharynx continued to feed normally as intact animals, while posterior pieces that retained the pharynx lost its function temporarily. The growth rate was similar amongst all pieces across 50 days. Anterior mouthless pieces regenerated the pharynx and mouth significantly faster than posterior mouthless pieces. After 50 days, the relative position of the mouth along the body reached values close to intact animals in all regenerating pieces. In general, anterior pieces showed higher survival and regenerated faster than posterior fragments, which agrees with observations with other planarian species. However, surviving posterior pieces were able to retain the proportions of intact animals as well. Our results suggest that L. abundans has a good regenerative capacity similar to many freshwater planarians.