Gazelle : The Palestinian Biological Bulletin (ISSN 0178 – 6288) . Number 126, June 2015, pp. 1-16. | Page 2

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Helix aspersa (O. F. Müller, 1774).
https://en.wikipedia.org/wiki/Helix_aspersa#mediaviewer/File:Snail1web.jpg
The class Gastropoda contains a vast total of named species, second only to
the insects in overall number. The fossil history of this class goes back to the Late
Cambrian. There are 611 families of gastropods known, of which 202
are extinct and appear only in the fossil record (Wikipedia).
Gastropoda (previously known as univalves and sometimes spelled
"Gasteropoda") are a major part of the phylum Mollusca, and are the most highly
diversified class in the phylum, with 60,000 to 80,000 living snail and slug
species. The anatomy, behavior, feeding, and reproductive adaptations of
gastropods vary significantly from one clade or group to another. Therefore, it is
difficult to state many generalities for all gastropods (Wikipedia).
The class Gastropoda has an extraordinary diversification of habitats.
Representatives live in gardens, woodland, deserts, and on mountains; in small
ditches, great rivers and lakes; in estuaries, mudflats, the rocky intertidal, the
sandy subtidal, in the abyssal depths of the oceans including the hydrothermal
vents, and numerous other ecological niches, including parasitic ones
(Wikipedia).
Although the name "snail" can be, and often is, applied to all the members of this
class, commonly this word means only those species with an external shell large
Gazelle : The Palestinian Biological Bulletin – Number 126 – June 2015