Gazelle : The Palestinian Biological Bulletin (ISSN 0178 – 6288) . Number 120, December 2014, pp. 30-53. | Page 6

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Description and Distinctive Features:
Shell Description
The shell of Sphincterochila boissieri is covered perforate, thick, irregularly striated,
somewhat effulgent, cretaceous and colored white. It has 5 slightly convex
whorls. The last whorl is deflected anteriorly. The aperture has a thick lip,
projecting internally above in two thick, subconfluent tubercles.
The average width of the shell is 25 mm (Wikipedia).

Anatomy and Physiology
The average body mass of Sphincterochila boissieri is around 4.3 g. Such mass is
divided evenly between the shell and the animals’ soft parts. Schmidt-Nielsen et
al., in 1971, found that 56% of the animal’s body mass was contained in its shell.
About 80 to 90% of the mass of the soft body parts is composed of water
(according to the Yom-Tov 1970). In average, soft body parts contain 81% of
water (nearly 1400 mg of water), 11% of proteins, 4% of ash, and little other
organic matter. Sphincterochila boissieri has no energy reserves and the amount of
lipids it contains is a fraction of 1%, which is considered to be extremely low
(Wikipedia).

The New Umm Dimna White Desert Land Snail Subspecies Sphincterochila boissieri
ummdimna Khalaf, 2014 from Umm Dimna (Dimona) Area in Al-Naqab (Negev) Desert,
Occupied Palestine. Photo by the Author. 22.12.2014.
https://www.flickr.com/photos/50022881@N00/16182869851/
Gazelle : The Palestinian Biological Bulletin – Number 120 – December 2014