123 D24. Paleontology, Morphology and Systematics

Monday, 5 November 2018
1:30 PM - 5:30 PM
Room 143-144

ELASMOBRANCH (CHONDRICHTHYES: ELASMOBRANCHII) FAUNAL COMPLEX FROM LATE ALBIAN (EARLY CRETACEOUS) OF KANEV DISLOCATIONS, UKRAINE

Paper number: 123-6
Program: Technical Sessions
Time: 2:45 PM – 3:00 PM

Authors

Abstract

During Albian stage of Early Cretaceous cartilaginous fish experienced a rapid diversification event that lead to the exploitation of ecological niches previously unoccupied by them. There are few locations in the world where marine vertebrate complexes of this age can be studied. Sampling from six thin layers of quartz-glauconite sands in Kanev dislocations, Ukraine yielded more than three thousand vertebrate specimens, including elasmobranch teeth, chimaera dental plates, fish and sauropsid teeth and bones. Our study represents the first illustrated and detailed description of elasmobranch teeth from Ukrainian Albian deposits since Rogovich, 1860 monograph. Rogovich described several new species from this location and we got a chance to include in this work some of his specimens currently housed in the National Natural History Museum of National Academy of Sciences of Ukraine. This lead to resurrection of some of his species names, notably Polyacrodus bidentatus, Synechodus kessleri, Heterodontus minutus, Paraisurus monstrosus and Archaeolamna striata. In addition, our research provides insight into the systematics of Albian species of Synechodus and Heterodontus, specifically S. nitidus and S. tenuis validity and H. upnikensis dental morphology.

Studied complex, consisting of both our and Rogovich specimens, includes a typical benthic species group of synechodontiform, bullhead, angel, carpet and dogfish sharks. Strangely, batoid and hybodont finds are very rare, Meristodonoides teeth are present only in one layer of sands while lamniform sharks are the most common shark taxon. Lamniformes in Kanev Albian displays the highest ecological diversity, with small sand tiger shark species, early pseudoscapanorhynchids and large carnivorous sharks Cretoxyrhina and Cretolamna. Most importantly, Paraisurus and Cretoxyrhina vraconensis findings confirm Late Albian age of these deposits since they are usually described in geological literature non-specifically as Albian-Cenomanian.

Geological Society of America Abstracts with Programs. Vol. 50, No. 6

doi: 10.1130/abs/2018AM-320036

© Copyright 2018 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.