Trematosauridae
Encyclopedia
Trematosauridae are a family of large temnospondyl
amphibians with many members. They first appeared during the Olenekian stage
of the Early Triassic
, and existed up until around the Carnian stage
of the Late Triassic
, although by then they were very rare. By the Middle Triassic
they had become widespread throughout Laurasia
and Gondwana
with fossils being found in Europe, Asia, Madagascar, and Australia.
They are one of the most derived families of the Trematosauroidea
superfamily in that they are the only family that have fully marine lifestyles. Long, slender snouts that are characteristic of the trematosaurids, with some members having rostrums
resembling those of modern-day gavials. Traditionally, two subfamilies within Trematosauridae can be identified, the relatively short-nosed Trematosaurinae
and the long-nosed Lonchorhynchinae
.
Temnospondyli
Temnospondyli is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carboniferous, Permian, and Triassic periods. A few species continued into the Cretaceous. Fossils have been found on every continent...
amphibians with many members. They first appeared during the Olenekian stage
Olenekian
In the geologic timescale, the Olenekian is an age in the Early Triassic epoch or a stage in the Lower Triassic series. It spans the time between 249.7 ± 0.7 Ma and 245 ± 0.7 Ma . The Olenekian follows the Induan and is followed by the Anisian.The Olenekian saw the deposition of a large part of the...
of the Early Triassic
Early Triassic
The Early Triassic is the first of three epochs of the Triassic period of the geologic timescale. It spans the time between 251 ± 0.4 Ma and 245 ± 1.5 Ma . Rocks from this epoch are collectively known as the Lower Triassic, which is a unit in chronostratigraphy...
, and existed up until around the Carnian stage
Carnian
The Carnian is the lowermost stage of the Upper Triassic series . It lasted from about 228.7 till 216.5 million years ago . The Carnian is preceded by the Ladinian and is followed by the Norian...
of the Late Triassic
Late Triassic
The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...
, although by then they were very rare. By the Middle Triassic
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided. It spans the time between 245 ± 1.5 Ma and 228 ± 2 Ma...
they had become widespread throughout Laurasia
Laurasia
In paleogeography, Laurasia was the northernmost of two supercontinents that formed part of the Pangaea supercontinent from approximately...
and Gondwana
Gondwana
In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...
with fossils being found in Europe, Asia, Madagascar, and Australia.
Trematosauroidea
Trematosauroidea are an important group of Triassic Temnospondyl amphibians. They flourished briefly during the Early Triassic, occurring worldwide before declining at the start of the Middle Triassic, although the group continued until the Late Triassic. They were medium-sized temnospondyls with...
superfamily in that they are the only family that have fully marine lifestyles. Long, slender snouts that are characteristic of the trematosaurids, with some members having rostrums
Rostrum (anatomy)
The term rostrum is used for a number of unrelated structures in different groups of animals:*In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes....
resembling those of modern-day gavials. Traditionally, two subfamilies within Trematosauridae can be identified, the relatively short-nosed Trematosaurinae
Trematosaurinae
Trematosaurinae is a subfamily of temnospondyl amphibians within the family Trematosauridae.-External links:*...
and the long-nosed Lonchorhynchinae
Lonchorhynchinae
Lonchorhynchinae is a subfamily of temnospondyl amphibians within the family Trematosauridae.-External links:*...
.
External links
- Trematosauridae at PalaeosPalaeosPalaeos.com is a web site on biology, paleontology, cladistics and geology and which covers the history of Earth. The site is well respected and has been used as a reference by professional paleontologists such as Michael J. Benton, the professor of vertebrate palaeontology in the Department of...