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a subclass of extinct reptiles of the late Carboniferous to middle Jurassic periods. They were the most widely distributed and best-adapted land vertebrates of the late Paleozoic era. Most of the Synapsida were predators, although there were also herbivorous members. It is possible that the higher Synapsida were warm blooded. Numerous remains have been found on all continents except Australia. In the USSR fossils have been found in the northern European part in the Northern Dvina, Middle Volga, and Ural regions. The subclass comprises two orders, Pelycosauria and Therapsida, with about 60families. They are important in explaining the evolution of the higher vertebrates.


Efremov, I. A. “Fauna nazemnykh pozvonochnykh v permskikh medistykh peschanikakh Zapadnogo Priuraria.” Tr. Paleontologicheskogo in-ta AN SSSR, 1954, vol. 54.
Orlov, lu. A. “Khishchnye deinotsefaly fauny Isheeva.”/6/W., 1958, vol. 72.
Osnovy paleontologii, vol. 12: Zemnovodnye, presmykaiushchiesia i ptitsy. Moscow, 1964.


References in periodicals archive ?
In addition, the scoring of Mesosauridae, Millerettidae and Captorhinidae is corrected to '0' as the maxilla and quadratojugal are clearly separated by the jugal in these taxa (Gow, 1972; Modesto, 2006; Clark and Carroll, 1973) and to '0&1' for synapsids as these bones are connected in caseids, eothyrids and some varanopids but separated in other varanopids and ophiacodontids (Berman et al., 1995; Brinkman, 1988; Langston, 1965; Laurin and Reisz, 1995; Romer and Price, 1940).
Furthermore, the character is also polymorphic in synapsids, because caseids and varanopids have a quadratojugal contribution to the lateral temporal fenestra but eothyrids and ophiacodontids do not (Berman et al., 1995; Brinkman, 1988; Langston, 1965; Laurin and Reisz, 1995; Romer and Price, 1940).
Synapsid phylogeny and the origin of mammalian endothermy.
Systematics of the nonmammalian Synapsida and implications for patterns of evolution in synapsids. Pp.
Mammals are termed synapsids because they evolved from animals with one skull opening behind each eye.
During the Middle Triassic, however, synapsids appear to be generally uncommon in tropical to subtropical Pangaean strata (as is the case for the Economy Member of the Wolfville Formation) while they are abundant at higher latitudes in both hemispheres (Sues and Fraser 2010).
This new species belongs to a group of animals called synapsids. Synapsida includes a number of extinct lineages that dominated the communities on land in the Late Permian (260-252 million years ago), as well as living mammals and their direct ancestors.