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Carbonate Deposits in Marine Fish Intestines: A New Source of Biomineralization
Limnology and Oceanography
  • Patrick J. Walsh, University of Miami
  • Patricia Blackwelder, University of Miami
  • Kenneth A. Gill, University of Miami
  • Eva Danulat, University of Victoria - Canada
  • Thomas P. Mommsen, University of Victoria - Canada
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Marine teleostean fish are hypo-osmotic to seawater. As part of a multiorgan osmoregulatory strategy they drink seawater and selectively absorb water and minerals across the intestinal epithelium. Notably, divalent cations (Ca2+ and Mg2-) are left behind. We report here that in the gulf toadfish, Opsanus beta, the ionic by-products of osmoregulation in the intestine contribute to de novo formation of a carbonate mineral, tentatively identified as calcian kutnohorite. Our data suggest that intestinal mineralization is a general feature of osmoregulation in marine teleosts and that this process is an unrecognized and possibly substantial source of marine carbonate sediments.

©1991, by the American Society of Limnology and Oceanography, Inc.

Citation Information
Patrick J. Walsh, Patricia Blackwelder, Kenneth A. Gill, Eva Danulat, et al.. "Carbonate Deposits in Marine Fish Intestines: A New Source of Biomineralization" Limnology and Oceanography Vol. 36 Iss. 6 (1991) p. 1227 - 1232 ISSN: 0024-3590
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