Ontogeny and Variability in Ribbing of Late Valanginian Lamellaptychi (Ammonitina)

0462392 - ÚGN 2017 RIV PL eng J - Journal Article
Vašíček, Zdeněk - Klein, J. - Janssen, N. M. M.
Ontogeny and Variability in Ribbing of Late Valanginian Lamellaptychi (Ammonitina).
Annales Societatis Geologorum Poloniae. Roč. 86, č. 1 (2016), s. 17-28. ISSN 0208-9068
Institutional support: RVO:68145535
Keywords : Lamellaptychi * Mortilletilamellaptychus * ontogeny * Late Valanginian * south-eastern France
Subject RIV: DB - Geology ; Mineralogy
Impact factor: 0.833, year: 2016
http://www.asgp.pl/sites/default/files/volumes/86_1_017_028.pdf

Late Valanginian (Early Cretaceous) lamellaptychi of the genus Mortilletilamellaptychus were collec-ted from seven ammonite-controlled sections in south-eastern France demonstrate distinct changes in ribbing during growth. Simpler juvenile ribbing, which is essentially uniform for all of the specimens studied, differs distinctly from the complicated arrangement of the adult ribs. Changes in ribbing orphology were observed in the five species studied, two of which were identified as new (i.e. Mortilletilamellaptychus heterocostatus sp. nov. and
M. bicostatus sp. nov.).
Permanent Link: http://hdl.handle.net/11104/0261862