Naslov
The shell mineralogy of subterranean snails Zospeum alpestre (Freyer 1855) and Zospeum isselianum (Pollonera 1886) (Mollusca: Gastropoda: Carychiidae)

Autori
Medaković, Davorin ; Slapnik, Rajko ; Gržeta, Biserka ; Popović, Stanko

Izvornik
Periodicum biologorum (0031-5362) 101 (1999), (2); 143-149

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Sažetak
Biomineralization processes of Gastropod (Molluscan) species depend on local ecological conditions, as well as on the genetic code of particular species. Also, molluscan shells and fossils are a basis for numerous biological, mineralogical, geological, chemical or other complex studies. The aim of research was to establish influence of ecological characteristics on mineral components and phase fractions of subterranean gastropod shells. Mineral composition of the species as possible valid taxonomical character was considered. The subterranean snails Zospeum alpestre (Freyer 1855) and Zospeum isselianum (Pollonera 1886) were sampled in four caves in the Slovenian Kamnik - Svinja Alps. X-ray diffraction (XRD) was applied in study of mineral components and phase fractions of gastropod shells. The contents of minerals were defined by quantitative X-ray phase analysis. Diffraction patterns showed that aragonite was a dominant component in the shells of genus Zospeum. Besides aragointe, calcite was registered in amounts of 1 to almost 37%. The shells of Z. alpestre contained in their inner layer 3% of quartz (SiO2) and Z. isselianum sampled on Stn 4, 5% of quartz. An outer shell layer of Z. isselianum sampled on both localities showed presence of phase Ca2Si (5 to 10%). This phase has never been recorded before as constituent of gastropod (even Molluscan) shells, and could b econsidered as a valid mineralogical character of Z. isselianum species. The mineral components of the inner shell layer of the Z. alpestre and Z. isselianum differed according to the sampling place, indicating local-environmental influence on biomineralization processes. This result has equally taxonomic and ecological significance.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

Napomena
Časopis je naveden u Pravilniku NN 2/97

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