Classification
Domain: Eukarya
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: Stylommatophora
Family: Valloniidea
Genus: Planogyra
Species: asteriscus
Planogrya asteriscus is commonly referred to as the eastern whorl snail. It is referred to as the eastern whorl snail, because of its four distinct whorls, and is more common to the eastern hemisphere of the world (Martin, 2000). The eastern whorl snail is classified as Eukarya and Animalia because it is a living organism. It is considered a mollusca because it is an invertebrate with an exoskeleton (Encyclopedia, 2009). Like all gastropods, it goes through torsion. Torsion is the process in which the visceral mass rotates so that its anus is located in the anterior portion of the body (the frontal portion by the head). Gastropods also have a muscular foot which is used for locomotion. They are able to move by contraction and expansion of the ventral muscular foot. Glands in the foot secrete mucus which makes it easier for them to glide over rough grounds (Martin, 2000). Members of the order stylommatophora have two retractable tentacles. The tentacles located on the anterior portion of the body contain the eyes at the tips of them (Encyclopedia, 2009).