Bert D. (2008) Etude de Paraspidoceras colloti ZEISS, 1962 (Aspidoceratidae ZlTTEL, 1895, Ammonitina) au sommet de la sous-zone a Vertebrale (Oxfordien moyen, zone à Plicatilis) du Sud-Est de la France // Revue de Paléobiologie. V.27. no.2. P.335-356. pdf: http://rogov.zwz.ru/Bert,2008.pdf
Discovery of a Paraspidoceras sample in a layer precisely dated of the Arkelli Horizon (Vertebrale Sub-zone, Plicatilis Zone) in the Montagne du Cheiron (Alpes-Maritimes, SE France) allows, for the first rime, to make a palaeobiological study. lts affinities allow to attribute it to the bad known species Paraspidoceras colloti Zeiss, 1962. Its morphological and stratigraphical characteristics may place this form at the origin of Paraspidoceras helymense GEMMELLARO, 1874 or Paraspidoceras berckhemeri ZEISS, 1962 populutions-like via intermediare like (?) Paraspidoceras blumbergense ZEISS, 1962. The problem of the dimorphism among the Paraspidoceras is considered, probable microconchs arc to search among «large Mirosphinctes» forms. On the taxonomic level, the abandon of the use of Paraspidoceras edwasianum (D'ORBIGNY) is recommended (nb: there is no any information concerning the latter species at the body of the text, it mentioned at the abstracts only).
Ammonites close resembling these Paraspidoceras scarcely occur also at the Russian Platform, where these ammonites co-occur with other Submediterranean taxa, such as Gregoryceras, Neoprionoceras etc. Their stratigraphical position lies more or less close to ther same level and perhaps coincides with "Platysphinctes event"
Paraspidoceras sp., Mikhalenino section, Kostroma region, scale bar=1 cm