Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 2
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Campyloprion Eastman, 1902 is a chondrichthyan having an arched symphyseal tooth whorl similar to that of

Helicoprion Karpinsky, 1899, but less tightly coiled. The holotype of Campyloprion annectans Eastman, 1902,

the type species of Campyloprion, is of unknown provenance, but is presumed to be from the Pennsylvanian

of North America. Campyloprion ivanovi (Karpinsky, 1922) has been described from the Gzhelian of Russia.

A partial symphyseal tooth whorl, designated as Campyloprion cf. C. ivanovi, is reported from the Missourian

Tinajas Member of the Atrasado Formation of Socorro County, New Mexico, USA. Partial tooth whorls from

the Virgilian Finis Shale and Jacksboro Limestone Members of the Graham Formation of northern Texas, USA,

are designated as Campyloprion sp. Two partial tooth whorls from the Gzhelian of Russia that were previously

referred to C. ivanovi are designated as Campyloprion cf. C. annectans. The age of Toxoprion lecontei (Dean,

1898), from Nevada, USA, is corrected from the Carboniferous to the early Permian. An alternative interpretation

of the holotype of T. lecontei is presented, resulting in a reversal of its anterior-to-posterior orientation. The

genera Helicoprion, Campyloprion, and Shaktauites Tchuvashov, 2001 can be distinguished by their different

spiral angles.

Go to article

Authors and Affiliations

Itano Wayne M.
Lucas Spencer G.
Download PDF Download RIS Download Bibtex

Abstract

The Indian Mesozoic dinosaur record is famous for documenting significant aspects of dinosaur evolution during the Triassic, Jurassic and Cretaceous periods. The Cenomanian–Turonian Nimar Sandstone, Lower Narmada valley, has produced fragmentary skeletal remains of Sauropoda indet. The Maastrichtian Lameta Formation has yielded at least 6 valid sauropod taxa and indeterminate titanosaurid remains, and at least 11 named (but likely oversplit) theropod taxa, i.e., 3 smaller-bodied species and 8 medium-to-large sized theropods. Apart from skeletal remains, Infra- and Intertrappean beds of peninsular India have yielded more than 10,000 dinosaur eggs belonging to 5 oofamilies and 15 oospecies. Most of the Indian ootaxa show distinct affinities with the Late Cretaceous ootaxa of four other continental areas – Spain, France, Argentina and Morocco. The presence of the two dominant oofamilies, Fusioolithidae and Megaloolithidae, in the Infra- and Intertrappean localities of peninsular India and three different continents (South America, Europe and Africa) further shows an ancient Gondwanan affinity and basic terrestrial association among these three landmasses. Based on the phylogenetic analysis of skeletal material, the most plausible pathway of dinosaur dispersal between India and Madagascar took place during the Late Cretaceous. The other conceivable dispersal pathway for the small animals was between India and Asia by means of the Kohistan Dras Volcanic Arc or a northeast pathway through Somalia, while the very large vertebrates, like theropod dinosaurs, may have emerged as a component of a ‘Pan Gondwanan’ model.
Go to article

Authors and Affiliations

Ashu Khosla
1
Spencer G. Lucas
2

  1. Department of Geology, Panjab University, Sector-14, Chandigarh-160014, India
  2. New Mexico Museum of Natural History, 1801 Mountain Rd. NW, Albuquerque, NM 87104, USA

This page uses 'cookies'. Learn more