Lysorophia

Lysorophians
Temporal range: Pennsylvanian–Cisuralian
Life restoration of Brachydectes newberryi
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: "Amphibia" (wide sense)
Subclass: †Lepospondyli
Order: †Lysorophia
Romer, 1930
Family: †Cocytinidae
Cope, 1875
Genera
Synonyms

Lysorophia is an order of aquatic Carboniferous and Permian amphibians within the extinct subclass Lepospondyli. Lysorophians resembled small snakes, as their bodies are extremely elongate. There is a single family, the Cocytinidae (previously known as Lysorophidae). Currently there are around five genera included within Lysorophia.

Description

The skull is lightly built and open, with large orbits and fenestrae. The intertemporal, supratemporal, postfrontal, and jugal bones of the skull have disappeared. The mandibles are short, and the maxilla and premaxilla freely movable.

Life restoration of Lysorophus tricarinatus showing speculative egg-coiling behavior.

The torso is very elongate, the limbs diminutive or absent, and the tail short. There are up to 99 pre-sacral (i.e. not including the hips and tail) vertebrae.

Based on morphology of the cranio-vertebral articulation, Lysorophids are usually considered to be related to the Microsauria, although the pattern of bones of the skull is very different.[1]

Distribution

San Miguel County, New Mexico San Juan County, Utah Baylor County, Texas Noble County, Oklahoma Westmoreland, Kansas Peru, Nebraska Falmouth, Kentucky Danville, Illinois Mazon Creek Dunkard Creek Jarrow Toftshaw NièvreLysorophia (geographic distribution).png
    Pennsylvanian (Upper Carboniferous) sites
    Permian sites
    Doubtful lysorophian site
Geographic distribution of Lysorophia after Wellstead (1991)

Lysorophians are known mainly from the Pennsylvanian and Early Permian of North America.[2] In North America, fossils of lysorophians have been found from places such as the Chinle Formation in San Juan County, Utah and the Mazon Creek fossil beds in Grundy County, Illinois. Carboniferous lysorophians are also known from Europe, having been found from England and Ireland. Possible remains of a lysorophian have also been found from La Machine, France, although they may belong to an aïstopod.[1][3]

References

  1. ↑ 1.0 1.1 Wellstead, C. F. (1991). "Taxonomic revision of the Lysorophia, Permo-Carboniferous lepospondyl amphibians" (PDF). Bulletin of the American Museum of Natural History 209: 1–90.
  2. ↑ Cannatella, D.C.; Vieites D.R., ZHang P., Wake M.H. & Wake D.B. (2009). "Amphibians (Lissamphibia)". In Hedges S.B. & Kumar S. The Timetree of Life. Oxford University Press. p. 354. ISBN 9780191608988. Retrieved 3 December 2012.
  3. ↑ Baird, D. (1964). "The aïstopod amphibians surveyed". Brevioria 206: 1–17.

General references

  • Carroll, RL (1988), Vertebrate Paleontology and Evolution, WH Freeman & Co. p. 180
  • von Zittel, K.A (1932), Textbook of Paleontology, C.R. Eastman (transl. and ed), 2nd edition, vol.2, p. 225-6, Macmillan & Co.

External links