Gazelle : The Palestinian Biological Bulletin (ISSN 0178 – 6288) . Number 120, December 2014, pp. 30-53. | Page 9

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Dormant snails experience water loss of 0.5 mg per day per snail in summer,
with a very low oxygen consumption rate. For these reasons, dormant
Sphincterochila boissieri can survive severe droughts for several years (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: Prof. Dr. Sc. Norman Ali Bassam Ali Taher KhalafSakerfalke von Jaffa. 22.12.2014.
https://www.flickr.com/photos/50022881@N00/16196488776/

Life Cycle
Sphincterochila boissieri is active for a few days only after rainfall during the
winter season, from November to March. At this time of the year they feed, mate,
and lay eggs. Thus these snails are active for only 5-7% of the year (nearly 18 to
26 days), and aestivate during all the rest of the time (Wikipedia).
Dormant snails are known to have survived in museum collections for up to 6
years. Schmidt-Nielsen et al. in 1971 estimated their life span according to their
oxygen consumption as being nearly 8 years (Wikipedia).
Gazelle : The Palestinian Biological Bulletin – Number 120 – December 2014