Hapsidopareiontidae is an extinct

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of tuditanomorph

microsaur Microsauria ("small lizards") is an extinct, possibly polyphyletic order of tetrapods from the late Carboniferous and early Permian periods. It is the most diverse and species-rich group of lepospondyls. Recently, Microsauria has been considere ...

s. Hapsidopareiontids are known from the

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of the

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and possibly

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and the

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. Hapsidopareiontids are characterized by a large temporal embayment near the cheek region in which the quadratojugal is greatly reduced or absent. Members of Ostodolepidae, another microsaur family, also possess temporal embayments, but they not as extensive as those of hapsidopareiontids, which extend into the

skull roof The skull roof, or the roofing bones of the skull, are a set of bones covering the brain, eyes and nostrils in bony fishes and all land-living vertebrates. The bones are derived from dermal bone and are part of the dermatocranium. In comparati ...

. In hapsidopareiontids, the embayment may have provided space for an enlarged jaw adductor musculature, although certain characteristics of the skull do not support this idea. '' Hapsidopareion'' and ''

Llistrofus ''Llistrofus'' is an extinct genus of early Permian microsaur within the family Hapsidopareiidae that is known from Oklahoma. Discovery ''Llistrofus'' was described by Canadian paleontologists Robert Carroll and Pamela Gaskill in 1978. The g ...

'' both possess this embayment, but in ''

Saxonerpeton ''Saxonerpeton'' is an extinct genus of microsaur of the family Hapsidopareiontidae. Fossils have been found from Early Permian strata near Dresden, Germany. See also * List of prehistoric amphibians References External links''Saxonerpeton' ...

'', the temporal region is complete. The lack of a temporal embayment may exclude ''Saxonerpeton'' from Hapsidopareiontidae; Bolt and Rieppel (2009) considered Hapsidopareiontidae to include only ''Hapsidopareion'' and ''Llistrofus'' because of this.

References

Prehistoric amphibians of Europe Prehistoric amphibians of North America Permian amphibians Cisuralian first appearances Cisuralian extinctions {{permian-animal-stub