Gharial

Gharial Fossil range: Late Cretaceous - Recent
Dyrosaurus phosphaticus, a crocodilian from the Lower Eocene of North Africa that resembles modern-day gharials.
Scientific classification
Class:	Reptilia
Order:	Crocodilia
Family:	Gavialidae
Genus:	Gavialis

The fossil history of the Gavialoidea is quite well known, with the earliest examples diverging from the other crocodilians in the Late Cretaceous. The most distinctive feature of the group is the very long, narrow snout, which is an adaptation to a diet of small fish. Although gharials have sacrificed the great mechanical strength of the robust skull and jaw that most crocodiles and alligators have, and in consequence cannot prey on large creatures, the reduced weight and water resistance of their lighter skull and very narrow jaw gives gharials the ability to catch rapidly moving fish, using a side-to-side snapping motion.

The earliest gharial may or may not have been related to the modern types: some died out at the same time as the dinosaurs (at the end of the Cretaceous), others survived until the Early Eocene The modern forms appeared at much the same time, evolving in the estuaries and coastal waters of Africa, but crossing the Atlantic to reach South America as well. At their peak, the Gavialoidea were numerous and diverse, they occupied much of Asia and America up until the Pliocene. One species, Rhamphosuchus crassidens of India, is believed to have grown to an enormous 15 meters (~50 feet) or more. Toyotamaphimeia Machikanensis, meaning “Luxuriant-Jewel-Princess of Mt. Machikane”, inhabited the mid Neogene-the mid Quaternary period of Japan & reached a length of 7.7m.

Taxonomy

The gharial and its extinct relatives are grouped together by taxonomists in several different ways:

• If the three surviving groups of crocodilians are regarded as separate families, then the gharial becomes one of two members of the Gavialidae, which is related to the families Crocodylidae (crocodiles) and Alligatoridae (alligators and caymans).
• Alternatively, the three groups are all classed together as the family Crocodylidae, but belong to the subfamilies Gavialinae, Crocodylinae, and Alligatorinae.
• Finally, palaentologists tend to speak of the broad lineage of gharial-like creatures over time using the term Gavialoidea.

Janke et al. (2005), using molecular genetic evidence, found the gharial and the false gharial (Tomistoma) to be close relatives, and placed them together in the same family.

Common names include: Indian gharial, Indian gavial, Fish-eating crocodile, Gavial del Ganges, Gavial du Gange, Long-nosed crocodile, Bahsoolia, Nakar, Chimpta, Lamthora, Mecho Kumhir, Naka, Nakar, Shormon, Thantia, Thondre, Garial.

Classification

• Order Crocodilia
  • Superfamily Gavialoidea

• • • • • Genus †Eothoracosaurus
        • Genus †Thoracosaurus
        • Genus †Eosuchus
        • Genus †Argochampsa
    • Family Gavialidae
      • Subfamily Gavialinae
        • Genus Gavialis
          • Gavialis gangeticus - modern gharial
          • †Gavialis curvirostris
          • †Gavialis breviceps
          • †Gavialis bengawanicus
          • †Gavialis lewisi
      • Subfamily Tomistominae
        • Genus Tomistoma
          • Tomistoma schlegelii, false gharial or Malayan gharial
          • †Tomistoma lusitanica
          • †Tomistoma cairense
        • Genus †Eogavialis
          • †Eogavialis africanus
          • †Eogavialis andrewsi
        • Genus †Kentisuchus
        • Genus †Gavialosuchus
        • Genus †Paratomistoma
        • Genus †Thecachampsa
        • Genus †Rhamphosuchus
        • Genus †Toyotamaphimeia
      • Subfamily †Gryposuchinae
        • Genus †Aktiogavialis
        • Genus †Gryposuchus
        • Genus †Ikanogavialis
        • Genus †Siquisiquesuchus
        • Genus †Piscogavialis
        • Genus †Hesperogavialis