Polonoceras bashkiricum Bogoslovsky, 1971
Sugerowana cytacja: Dzik, J. 2015. Polonoceras bashkiricum Bogoslovsky 1971. Ikonoteka (http://ikonoteka.paleo.pan.pl/xwiki/bin/view/Species/Polonoceras+bashkiricum+)
Diagnoza Acute tips of auricles of the aperture; distinctly tabulate venter of mature specimens, rounded in juveniles. Porównanie The Frasnian-style suture and the subtrapezoidal cross section of the whorl make this specimen similar to the holotype of Linguatornoceras linguum. Conchs of the Famennian species are attributed to the genus , however, different from the Łagów specimen in having a very narrow flank lobe of the suture and rounded margins of the umbilicus. In the latter aspect, the specimen discussed resembles the stratigraphically older species attributed here to Gundolficeras korni (Becker, 1993) and Protornoceras simplicius, being different in the subtrapezoidal whorl section and deep flank lobe of the suture. Specimens from sample Ł-14 tentatively attributed to the latter species may also belong here, as well as the specimen from the Upper Łagów Beds illustrated by Sobolew (1914) as Tornoceras escoti Frech, 1902. The species seems both morphologically and stratigraphically transitional between P. sandbergeri and P. planum. Autekologia Występowanie geograficzne Jabłonna; Łagów-Dule; possibly also reworked at Sieklucki’s brickpit in Kielce. Zasięg czasowy Late K. crepida (bed 15) and probably the C. marginifera (bed 17) Zones; the C. marginifera Zone. Materiały muzealne ZPAL: 3 specimens. Literatura Dzik, J. 2006. The Famennian "Golden Age" of conodonts and ammonoids in the Polish part of the Variscan sea. Palaeontologia Polonica 63, 1-359. |
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