digplanet beta 1: Athena
Share digplanet:

Agriculture

Applied sciences

Arts

Belief

Business

Chronology

Culture

Education

Environment

Geography

Health

History

Humanities

Language

Law

Life

Mathematics

Nature

People

Politics

Science

Society

Technology

Acteosaurus
Temporal range: 99.6–89.3Ma
Late Cretaceous: Cenomanian - Turonian
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Scleroglossa
Family: Dolichosauridae
Genus: Acteosaurus
Meyer, 1860
Species
  • Acteosaurus tommasinii type Meyer, 1860
  • (?)A. crassicostatus Calligaris, 1993

Acteosaurus is an extinct genus of aquatic lizard that lived in the upper Cretaceous period. Its species, A. tommasinii and A. crassicostatus, were described in 1860 and 1993. Though A. crassicostatus is probably a junior synonym for Adriosaurus suessi, A. tommasinii was found to be similar to coniasaurs, mosasauroids, and a sister taxon to modern snakes in 2010.[1]

Etymology[edit]

The primary portion of Acteosaurus' name comes from Actaeon (/ækˈtən/; Greek: Άκταίων), a famous Theban hero who was hunted and killed by the goddess Artemis. The second part of the name is the Greek word sauros (σαυρος), which means "lizard" or "reptile". The type species was named after the botanist Muzio Giuseppe Spirito de Tommasini (1794—1879), the Podestà—or magistrate—of Trieste under the Habsburgs.[2]

Taxonony[edit]

Hermann von Meyer (1801-1869)

As a genus, Acteosaurus was described in 1860 by German paleontologist Christian Erich Hermann von Meyer. There exist two known species of Acteosaurus: A. crassicostatus and A. tommasinii. The latter is the type species, while A. crassicostatus was discovered in 1993.

A 2010 redescription of the type species found "monophyly of the clade Ophidiomorpha".[1] This included the Dolichosauridae, Pontosaurus, Aphanizocnemus, and Adriosaurus. Acteosaurus was found to be a basal ophidiomorph (similar to Adrisaurus) and sister taxon to the Ophidia, or modern snakes.[1]

Description[edit]

Acteosaurus is described as slender or snake-like, similar to other dolichosaurids.[3] Its shortened forelimbs and long tail help to distinguish it from other genera, and its vertebral column is similar to more modern varanid lizards.[3]

The holotype, when it was discovered, was unfortunately missing its head.[3] So, while Meyer was unable to come up with an exact number, he noted that Acteosaurus has at least 10 cervical vertebrae, and 27 dorsals. There are small articular processes on the trunk vertebrae, and it has long, narrow neural spines, and posteroventrally positioned, unfused haemal arches on the vertebrae of the tail. There is no pachyostosis, or bone thickening, in the vertebrae and ribs. The limbs are reduced in size, and though the forelimbs of Acteosaurus are fully developed, they are smaller than the hind limbs.[2] Acteosaurus' pelvic bone is flattened, has square-shaped pubic process, and a rectangular descending ramus.[1]

Distribution and habitat[edit]

The Istrian peninsula

Both Acteosaurus tommasinii and A. crassicostatus were found in the upper section of karst Cenomanian platy limestone, in Komen, Slovenia.[2][4] Komen is part of Istria, a peninsula on the Adriatic sea, and also a section of the Kras plateau. During the late Cretaceous, most of Europe was an island chain in the Tethys ocean,[5] and Acteosaurus' aquatic nature and similarity to mosasauroids suggests that it lived on the coast of one of these islands.[2]

See also[edit]

References[edit]

  1. ^ a b c d Palci, Alessandro; Caldwell, Michael (2010). "Redescription of Acteosaurus tommasinii von Meyer, 1860, and a discussion of evolutionary trends within the clade Ophidiomorpha". Journal of Vertebrate Paleontology 30: 94–108. doi:10.1080/02724630903409139. 
  2. ^ a b c d Wright, T. (1860). "On the Subdivisions of the Inferior Oolite in the South of England, compared with the Equivalent Beds of that Formation on the Yorkshire Coast". Quarterly Journal of the Geological Society 16: 1–48 [35, 31]. doi:10.1144/GSL.JGS.1860.016.01-02.06. 
  3. ^ a b c Gorjanovic-Kramberger, Carl. Trans, John D. Scanlon. AIGIALOSAURUS: A new lizard from the Cretaceous slates of the Island of Lesina with consideration of the previously described lacertids of Comen and Lesina. 1892"Rad" der südslavischen Akademie der Kunst und der Wissenschaft 109: 96-123, Pl. I, II.
  4. ^ Jurkovšek, Bogdan; Kolar-Jurkovšek, Tea (2007). "Fossil assemblages from the Upper Cretaceous Komen and Tomaj Limestones of Kras (Slovenia)". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 245: 83–92. doi:10.1127/0077-7749/2007/0245-0083. 
  5. ^ "Dinosaurs Rule the World: Late Cretaceous Period." In: Dodson, Peter & Britt, Brooks & Carpenter, Kenneth & Forster, Catherine A. & Gillette, David D. & Norell, Mark A. & Olshevsky, George & Parrish, J. Michael & Weishampel, David B. The Age of Dinosaurs. Publications International, LTD. Pp. 103-104. ISBN 0-7853-0443-6.

External links[edit]


Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Acteosaurus — Please support Wikipedia.
This page uses Creative Commons Licensed content from Wikipedia. A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia.

Youtube says it doesn't have anything for Acteosaurus.

We're sorry, but there's no news about "Acteosaurus" right now.

Loading

Oops, we seem to be having trouble contacting Twitter

Support Wikipedia

A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia. Please add your support for Wikipedia!

Searchlight Group

Digplanet also receives support from Searchlight Group. Visit Searchlight