Capitosauria is an extinct group of large
temnospondyl
Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carb ...
amphibians with simplified
stereospondyl vertebrae. Mainly living as
piscivore
A piscivore () is a carnivorous animal that eats primarily fish. The name ''piscivore'' is derived . Piscivore is equivalent to the Greek-derived word ichthyophage, both of which mean "fish eater". Fish were the diet of early tetrapod evoluti ...
s in lakes and rivers, the Capitosauria and its
sister taxon
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and ...
Trematosauria were the only major
labyrinthodont
"Labyrinthodontia" (Greek, 'maze-toothed') is an informal grouping of extinct predatory amphibians which were major components of ecosystems in the late Paleozoic and early Mesozoic eras (about 390 to 150 million years ago). Traditionally conside ...
s that existed during the
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Creta ...
in ecological niches broadly similar to those of modern
crocodile
Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant ...
s, and some grew to very large sizes. At 6 meters in length, the Mid-Triassic ''
Mastodonsaurus giganteus'' is not only thought to have been the largest capitosaur, but possibly also the largest amphibian to have lived.
The latest known remains are from the
Rhaetian
The Rhaetian is the latest age of the Triassic Period (in geochronology) or the uppermost stage of the Triassic System (in chronostratigraphy). It was preceded by the Norian and succeeded by the Hettangian (the lowermost stage or earliest ...
of Germany and are referred to ''
Cyclotosaurus
''Cyclotosaurus'' is an extinct genus of temnospondyl within the family Mastodonsauridae. It was of great size for an amphibian, had an elongated skull up to .
Etymology
The name means "round eared lizard" in Ancient Greek, derived from ro ...
''.
Capitosauria was first named by Schoch and Milner (2000) and further described by Yates and Warren (2000), who assigned ''
Lydekkerina'' and
Mastodonsauroidea
The Mastodonsauroidea are an extinct superfamily of temnospondyl amphibians known from the Triassic. Fossils belonging to this superfamily have been found in North America, Greenland, Europe, Asia, and Australia. The genus ''Ferganobatrachus ...
to it.
It was described by Damiani (2001) under the name Mastodonsauroidea.
In their phylogenetic analysis of temnospondyls, Ruta ''et al.'' (2007) placed ''Lydekkerina'' and its relatives within the clade
Rhytidostea, while placing only mastodonsauroid taxa within Capitosauria.
Phylogeny
Below is a
cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...
from Fortuny ''et al.'' (2011) showing the
phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
relationships of capitosaurs:
References
External links
Capitosauriain the
Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.
History
The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Paleo ...
Triassic temnospondyls
Triassic first appearances
Triassic extinctions
Capitosaurs
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