Askeptosauroidea
Encyclopedia
Askeptosauroidea is a superfamily of thalattosaur
s, a Triassic
group of marine reptile
s. Askeptosauroidea is one of two major subgroups of Thalattosauria, the other being Thalattosauroidea
. It includes the family
Askeptosauridae
and a more basal
form called Endennasaurus
.
from Wu et al. (2009) showing the phylogenetic relationships of Askeptosauroidea:
Thalattosaur
Thalattosaurs are a group of prehistoric marine reptiles which lived during the mid-late Triassic Period. Some species of thalattosaur grew to over 4 meters in length, including a long, flattened tail used in underwater propulsion...
s, a Triassic
Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
group of marine reptile
Marine reptile
Marine reptiles are reptiles which have become secondarily adapted for an aquatic or semi-aquatic life in a marine environment.The earliest marine reptiles arose in the Permian period during the Paleozoic era...
s. Askeptosauroidea is one of two major subgroups of Thalattosauria, the other being Thalattosauroidea
Thalattosauroidea
Thalattosauroidea is a superfamily of thalattosaurs, a Triassic group of marine reptiles. It was named in 1904 by paleontologist John Campbell Merriam to include the genus Thalattosaurus from California. Thalattosauroids are one of two groups of Thalattosauria, the other being Askeptosauroidea...
. It includes the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Askeptosauridae
Askeptosauridae
Askeptosauridae is a family of thalattosaurs within the superfamily Askeptosauroidea. Fossils have been found from Italy, Switzerland, and China. Askeptosaurids are distinguished from other thalattosaurs by their long necks and narrow skulls.-Classification:...
and a more basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
form called Endennasaurus
Endennasaurus
Endennasaurus is an extinct genus of thalattosaurian from the Upper Triassic of Italy....
.
Phylogeny
Below is a cladogramCladogram
A cladogram is a diagram used in cladistics which shows ancestral relations between organisms, to represent the evolutionary tree of life. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational...
from Wu et al. (2009) showing the phylogenetic relationships of Askeptosauroidea: