Paleontological Journal

, Volume 41, Issue 2, pp 198–206

Late Permian phylloclades of the new genus Permophyllocladus and problems of the evolutionary morphology of peltasperms

  • E. V. Karasev
  • V. A. Krassilov

DOI: 10.1134/S0031030107020104

Cite this article as:
Karasev, E.V. & Krassilov, V.A. Paleontol. J. (2007) 41: 198. doi:10.1134/S0031030107020104


Phylloclades from the Upper Permian (Tatarian) deposits of the Sokovka locality, Vladimir Region, showing gradational transformation of a planate scale-leaved shoot into a foliar organ, are assigned to the new genus Permophyllocladus (Peltaspermales?). The phylloclades are distinctly dorsoventral: scaly leaves and their rudiments are developed on the lower side and are only marked by suture lines on the cuticle of the opposite side. In epidermal characteristics, the phylloclades are similar to the leaves of peltasperms from coeval deposits. It is supposed that peltasperm leaves are of phylloclade origin and were formed by cohesion of units of a coniferoid scale-leaved shoot that resembles shoots of the Mesozoic family Hirmerellaceae (Cheirolepidiaceae), which also tend to develop phylloclades.

Key words

phyllocladespeltaspermsconifersleaf originPermianRussian Platform

Copyright information

© Pleiades Publishing, Ltd. 2007

Authors and Affiliations

  • E. V. Karasev
    • 1
  • V. A. Krassilov
    • 1
  1. 1.Paleontological InstituteRussian Academy of SciencesMoscowRussia