CLASSIFICATION OF PILA GLOBOSA : APPLE SNAIL
PHYLUM :- MOLLUSCA (Unsegmented bilaterally symmetrical and provided with visceral mass, foot and mantle. )
CLASS :- GASTROPODA (Visceral hump twisted.)
SUB-CLASS :- PROSOBRANCHIATA (Gills in front of heart.)
ORDER :- PECTINIBRANCHIATA (Ctenidium comb-like or monopectinate.)
SUB-ORDER :- TAENIOGLOSSA (Radula with 7 teeth in each row.)
GENUS :- Pila
SPECIES :- globoso
It is most common in India, U.S.A. and Europe.
HABIT AND HABITAT
Pila globosa is one of the largest fresh-water gastropod abundantly found in ponds, tanks, rice-fields and in water having succulent vegetation. They are amphibious. In winter they hibernate in the mud by the side of the pond and during prolonged drought they remain dormant.
GENERAL CHARACTERSTICS OF PILA GLOBOSA : APPLE SNAIL
- Commonly called as fresh-water apple snail.
- Body is covered by a thick yellow-coloured or brown globular univalve shell, comprising of body whorl, penultimate whorl and apex. Each division is separated by sutures.
- Surface of the shell is marked by lines of growth.
- Shell is spirally coiled round the axis, called the columella, and opens to the exterior by mouth of aperture.
- Type of coiling is right handed and is called as dextral.
- After removing the shell the soft part contains head, foot and visceral mass.
- Mouth of the shell is wide and covered by operculum, which is attached to the hinder part of the foot and shows many concentric rings of growth around nucleus, umblicus and columellar lip are closely placed.
- Head lies on the upper side and contains 1 pair of eyes. Foot is highly muscular and acts as creeping organ. Visceral mass spirally coiled and contains internal organs. It is covered by mantle or pallium. When the foot is protruded during living condition, the head, nuchal lobes, eyes, tentacles, etc. are distinctly seen. These structures are seen after removing the shell.
- Sexes are separate but without sexual dimorphism.
Pila is the slowest moving animal but it has great medicinal, experimental and study value.
The animal contains largest body whorl and all above features hence it is Pila.