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Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:Standardowy; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} An unusual occurrence of parasitic “Housean pits” in internal mould of ammonoid specimen referred to as Felisporadoceras cf. subvaricatum (Sobolew) from Middle Famennian of Poland are described. Hitherto the youngest representatives of goniatites showing a pitting on the internal moulds were known from the Middle Devonian (lower Givetian), thus, most probably the presented material constitutes the youngest world record of this phenomenon.
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Michał Rakociński (2012) studied this question.
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