APPEARANCE OF SCAPHITOMORPH MORPHOLOGY THROUGH MINIATURIZATION IN AN OXFORDIAN AMMONITE - SCAPHITODITES SCAPHITOIDES (COQUAND, 1853)

Authors
NEIGE P MARCHAND D ROSSI J LANCE J
Citation
P. Neige et al., APPEARANCE OF SCAPHITOMORPH MORPHOLOGY THROUGH MINIATURIZATION IN AN OXFORDIAN AMMONITE - SCAPHITODITES SCAPHITOIDES (COQUAND, 1853), Comptes rendus de l'Academie des sciences. Serie II. Sciences de la terre et des planetes, 325(4), 1997, pp. 281-284
Citations number
13
Categorie Soggetti
Geosciences, Interdisciplinary
Journal title
Comptes rendus de l'Academie des sciences. Serie II. Sciences de la terre et des planetes → ACNP
ISSN journal
12518050
Volume
325
Issue
4
Year of publication
1997
Pages
281 - 284
Database
ISI
SICI code
1251-8050(1997)325:4<281:AOSMTM>2.0.ZU;2-4
Abstract
The pyritized fossil-bearing marls of the Jura (Lower Oxfordian) conta in an ammonite that is remarkable because of its tiny adult size (less than 16 mm) and of the scaphitoidal coiling of its body chamber, whic h is similar to that of certain Cretaceous Scaphitaceae. Anatomical an d ontogenetic analysis demonstrates that these individuals, which are ascribed to Scaphitodites scaphitoides (Coquand, 1853), formed a singl e species. We argue that the genus Scaphitodites derived from Taramell iceras by a complex process of progenesis (sensu Landman et al., 1991) .