QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online February 6, 2004
Journal of Experimental Biology 207, 1017-1025 (2004)
Published by The Company of Biologists 2004
doi: 10.1242/jeb.00860

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gefen, E. Articles by Ar, A. Search for Related Content PubMed PubMed Citation Articles by Gefen, E. Articles by Ar, A.

Comparative water relations of four species of scorpions in Israel: evidence for phylogenetic differences

Eran Gefen^* and Amos Ar

Department of Zoology, Tel Aviv University, Ramat Aviv 69978, Israel

^* Author for correspondence (e-mail: erangef{at}post.tau.ac.il)

Accepted 31 December 2003

In an attempt to determine the nature of possible interspecific differences in osmotic responses to dehydration, the following species of two scorpion families were examined: Scorpio maurus fuscus (Scorpionidae) and Buthotus judaicus (Buthidae) from the mesic Lower Galilee (mean annual precipitation 525 mm); and Scorpio maurus palmatus (Scorpionidae) and Leiurus quinquestriatus (Buthidae) from the xeric Negev Desert (mean annual precipitation 100 mm).

When sampled in the laboratory following their capture, B. judaicus (548±38 mOsm l^–1; mean ± S.D.) and L. quinquestriatus (571±39 mOsm l^–1) had higher and less variable haemolymph osmolarities than the scorpionids occupying the same habitats (511±56 and 493±53 mOsm l^–1 for S. m. fuscus and S. m. palmatus, respectively).

In response to 10% mass loss when desiccated at 30°C, the haemolymph osmolarity of the two buthids increased by 5–9%, compared to ca. 23% in the two scorpionids. Buthids had lower water loss rates than scorpionids. The similar oxygen consumption rates, when converted to metabolic water production, imply a higher relative contribution of metabolic water to the overall water budget of buthids. This could explain why the osmoregulative capabilities exhibited by buthids are better than those of scorpionids.

We conclude that the observed interspecific differences in water and solute budgets are primarily phylogenetically derived, rather than an adaptation of the scorpions to environmental conditions in their natural habitat.

Key words: scorpion, haemolymph, osmolarity, desiccation, water budget, phylogenetic, osmoregulation

This article has been cited by other articles:

				E. Gefen and A. Ar The effect of desiccation on water management and compartmentalisation in scorpions: the hepatopancreas as a water reservoir J. Exp. Biol., May 15, 2005; 208(10): 1887 - 1894. [Abstract] [Full Text] [PDF]