ON THE TUBE ULTRASTRUCTURE AND ORIGIN OF CALCIFICATION IN SABELLIDS (ANNELIDA, POLYCHAETA) |
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Authors: | OLEV VINN HARRY A ten HOVE † and HARRY MUTVEI‡ |
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Institution: | Institute of Geology, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia;e-mail:; Zoological Museum, University of Amsterdam, POB 94766, 1090 GT Amsterdam, the Netherlands;e-mail:; Department of Palaeozoology, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden;e-mail: |
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Abstract: | Abstract: Tube ultrastructure of Jurassic and Cretaceous Glomerula is very similar to that of Recent Calcisabella , supporting the synonymy of these genera and the early Mesozoic origin of calcification in sabellids. Tube structure of serpulids differs from that of Glomerula ; calcareous tubes probably evolved convergently within Sabellida. The tube wall in Recent Glomerula piloseta is composed of subparallel lamellae of aragonitic, irregular spherulitic prisms in the inner layer, and spherulites in the outer layer. Calcified lamellae are separated by organic films of different thickness. The structure of the internal tube layer in Glomerula piloseta , and the structure of entire wall in fossil Glomerula , are similar to the tube structure of Dodecaceria (Polychaeta, Cirratulidae). The irregular spherulitic prisms of Glomerula are similar to those found in the external layer of Hydroides dianthus and the internal layer of Spiraserpula caribensis . |
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Keywords: | Polychaeta Sabellidae Glomerula Calcisabella tube ultrastructure biomineralization |
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