Sucker (zoology)

It acts as an adhesion device in parasitic worms, several flatworms, cephalopods, certain fishes, amphibians, and bats.

In parasitic annelids, flatworms and roundworms, suckers are the organs of attachment to the host tissues.

In tapeworms and flukes, they are a parasitic adaptation for attachment on the internal tissues of the host, such as intestines and blood vessels.

Densely packed muscle fibres link the sucker with the main body through the stalk.

The detailed structure of the suckers, presence or absence of hooks, and their exact position on the body are major taxonomic keys between species.

They are known to have muscular, glandular, and sensory components thought to play some role in blood feeding.

In other species like Anoplodiscus, the sucker is a posterior extension, connected to the main body through a small stalk.

[9][10] Annelid worms such as leeches all have an anterior (oral) sucker formed from the first six segments of their body, which is used to connect to a host for feeding.

They use a combination of mucus and suction (caused by concentric muscles in those six segments) to stay attached and secrete an anti-clotting enzyme, hirudin, into the host's blood stream.

The posterior is mainly used for leverage while the anterior sucker, consisting of the jaw and teeth, is where the feeding takes place.

[11] During locomotion directional movement of the body is done by successive attachment and detachment of the oral sucker and the acetabulum.

When the sucker attaches itself on an object, the infundibulum mainly provides adhesion while the central acetabulum is quite free.

They roost inside the rolled leaves of palm trees, using their suckers to attach themselves to the smooth surface.