Classification of Tapered Vertigo

Classification of Tapered Vertigo (Burch 1962)   
Domain - Eukarya  
Kingdom - Animalia
Phylum - Mollusca
Class - Gastropoda               
Subclass - Pulmonata
Order - Stylommatophora
Family - Pupillidae    
                                Subfamily - Vertigininae
                                Genus - Vertigo                                                                             
                                Species - elatior                                          
                                       Full name - Vertigo elatior Sterki, 1894

Why is the tapered vertigo classified as it is?
     The tapered vertigo is eukaryotic because it is multicellular and has membrane bound organelles.  It lands in the Kingdom Animalia by having a digestive system, reproductive structures, and being heterotrophic (Parker 2011).  Next, it is classified in the Phylum Mollusca because of the characteristics of lophotrochozoa, having bilateral symmetry, has more than two cell layers, a body type with three main parts (head/foot, mantle, and visceral mass), a complete digestive system, having a true coelom, body can vary in form (mollusk = soft body), may possess shells, has nervous system, open circulatory system (most), protostome development, and has gaseous exchange organs (Hickman 2009). Furthermore, the tapered vertigo is under the Class Gastropoda.  Most gastropods have a coiled shell that the body can be withdrawn into others have lost the shell, for example, the slugs (Myers and Burch 2001).  Gastropods can also be characterized by torsion, which allows them to twist or rotate the visceral mass and mantle so that the mantle cavity becomes anterior (Myers and Burch 2001).  This process occurs in the larval (veliger) stage which leads to the head and mouth being under the anus and twisting of the gut and nervous system (Myers and Burch 2001).  More specifically the tapered vertigo is classified in the subclass Pulmonata and order Stylommatophora which indicates that it is terrestrial (Burch and Myers 2008).   The adaptations to living in a terrestrial habitat include lungs, which are developed from the mantle (Burch and Myers 2008).  Other features of the Pulmonata subclass are having two pairs of tentacles and a highly concentrated nervous system (Burch and Myers 2008).  Common features of the shell from the Family Pupillidae include apex, suture, penultimate whorl, body whorl, palatal depression, crest, sinulus, and callus (Nekola and Coles 2010).

Figure 2. Diagram of Vertigo elatior showing features that are characteristic of the family Pupillidae (Nekola and Coles 2010).

Finally, the genus Vertigo refers to having a blunt summit,  a shade of brown, and glossy shells (Pilsbry 1948).  Vertigo's also have heads without tentacles (Pilsbry 1948).