Skin Resistance to Water Loss in Viperid Snakes

Razi Dmi’el

Abstract


Many desert snakes show reduced rates of cutaneous water loss (CWL) compared to species from more humid habitats. To investigate whether this reduction is due to climatic or experimental conditions or it may be attributed more to the taxonomic position of the snake, the skin resistance to water loss, Rs, was compared among four species of viperid snakes occupying in Israel different climatic regions and habitats: mesic Mediterranean (Vipera xanthina palaestinae), steppe and desert areas (Echis colorata), and extreme desert (Cerastes cerastes and Pseudocerastes persicus fieldi). Cutaneous and respiratory water loss, oxygen consumption, cloacal and skin temperatures were measured in these nocturnal snakes at three air temperatures (25, 30, and 35°C); the experimental values were then used to calculate the Rs. Cutaneous water loss of Vipera, the mesic-Mediterranean species, increased from 0.105 mg/(cm2  h) at 25°C to 0.175 mg/(cm2  h) at 35°C. These CWL are 2 to 2.8-fold higher than those of the desert species. Rs of Vipera decreased from 878 s/cm at 25°C to 706 s/cm at 35°C. Rs of the desert species were twice those obtained for Vipera (up to 1921 s/cm in Pseudocerastes at 35°C), and they increased with increasing experimental temperatures. These Rs changes, which probably reflect vasomotor responses, were more pronounced in Pseudocerastes, the desert species with the most conspicuous diurnal activity.

Keywords


Reptilia; Ophidia; Viperidae; cutaneous water loss; skin resistance; habitat aridity

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References


Ashkenazi S. and Hakham E. (1987), Names of the Vertebrates in Israel. Nature Conservation in Israel, Suppl. 1, Nature Reserves Authority, Jerusalem.

Baeyens D. A. and Rountree R. L. (1983), «A comparative study of evaporative water loss and epidermal permeability in an arboreal snake, Opheodrys aestivus, and a semi-aquatic snake, Nerodia rhombifera», Comp. Biochem. Physiol., 76A, 301 – 30.

Bentley P. J. and Schmidt-Nielsen K. (1966), «Cutaneous water loss in reptiles», Science, 151, 1547 – 1549.

Cohen A. C. (1975), «Some factors affecting water economy in snakes», Comp. Biochem. Physiol., 51A, 361 – 368.

Dmi’el R. (1972), «Effect of activity and temperature on metabolism and water loss in snakes», Am. J. Physiol., 223, 510 – 516.

Dmi’el R. (1985), «Effect of body size and temperature on skin resistance to water loss in a desert snake», J. Thermal. Biol., 10, 145 – 149.

Dmi’el R. and Zilber B. (1971), «Water balance in a desert snake», Copeia, 1971(4), 754 – 755.

Eynan M. and Dmi’el R. (1989), «Skin resistance to water loss in agamid lizards», in: Abstrs. of the Asiatic Herpetol. Res. Meeting, Huanshan, Anhui, China

Eynan M. and Dmi’el R. (1993), «Skin resistance to water loss in agamid lizards», Öcologia, 1993, 1 – 5.

Gans C., Krakauer T., and Paganelli C. V. (1968), «Water loss in snakes, interspecific and intraspecific variability», Comp. Biochem. Physiol., 27A, 747 – 761.

Kattan G. H. and Lillywhite H. B. (1989), «Humidity acclimation and skin permeability in the lizard Anolis carolinensis», Physiol. Zool., 62, 593 – 606.

Lahav S. and Dmi’el R. (1996), «Skin resistance to water loss in colubrid snakes: Ecological and taxonomic correlations», Ecoscience, 3, 135 – 139.

Landmann L. (1986), «The skin of reptiles: epidermis and dermis», in: J. Bereiter-Hahn, A. G. Matoltsy and K. S. Richards (eds.), Biology of the Integument. Vol. 2. Vertebrates, Springer, Berlin, pp. 150 – 187.

Landmann L. (1988), «The epidermal permeability barrier», Anat. Embryol., 178, 1 – 13.

Lillywhite H. B. and Maderson P. F. A. (1982), «Skin structure and permeability», in: C. Gans and F. H. Pough (eds.), Biology of the Reptilia. Vol. 12. Physiology, Acad. Press, New York, pp. 397 – 442.

Lillywhite H. B. and Sanmartino V. (1993), «Permeability and water relations of hygroscopic skin of the file snake, Acrochordus granulatus», Copeia, 1993(1), 99 – 103.

Marx H. and Rubb G. B. (1965), «Relationships and zoogeography of the viperine snakes (Family Viperidae)», Fieldiana. Zool., 44, 161 – 206.

Mautz W. J. (1982a), «Correlation of both respiratory and cutaneous water loss of lizards with habitat aridity», J. Comp. Physiol., 149, 25 – 30.

Mautz W. J. (1982b), «Patterns of evaporative water loss», in: C. Gans and F. H. Pough (eds.), Biology of the Reptilia. Vol. 12. Physiology, Acad. Press, New York, pp. 443 – 481.

McArthur A. J. (1981), «Thermal insulation and heat loss from animals», in: J. A. Clark (ed.), Environmental Aspects of Housing for Animal Production, Butterworths, London, pp. 37 – 60.

Mendelssohn H. (1963), «On the biology of the venomous snakes of Israel. Part 1», Israel J. Zool., 12, 143 – 170.

Mendelssohn H. (1965), «On the biology of the venomous snakes of Israel. Part 2», Israel J. Zool., 14, 185 – 212.

Monteith J. L. (1973), Principles of Environment Physics, Arnold, London.

Monteith J. L. and Campbell G. S. (1980), «Diffusion of water vapour through integuments — potential confusion», J. Thermal Biol., 5, 7 – 9.

Prange H. D. and Schmidt-Nielsen K. (1969), «Evaporative water loss in snakes», Comp. Biochem. Physiol., 28, 973 – 975.

Roberts J. B. and Lillywhite H. B. (1980), Lipid barrier to water exchange in reptile epidermis», Science, 207, 1077 – 1079.

Roberts J. B. and Lillywhite H. B. (1983), «Lipids and the permeability of epidermis of snakes», J. Exp. Zool., 228, 1 – 9.

Robertson S. L. and Smith E. N. (1982), «Evaporative water loss in the spiny soft-shelled turtle Trionyx spiniferus», Physiol. Zool., 55, 124 – 129.

Schmidt-Nielsen K. (1964), Desert Animals. Physiological Problems of Heat and Water, Oxford Univ. Press, London.

Spotila J. R. and Berman E. N. (1976), «Determination of skin resistance and the role of skin in controlling water loss in amphibians and reptiles», Comp. Biochem. Physiol., 55A, 407 – 411.


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