Malawania

Malawania is an extinct genus of basal thunnosaur ichthyosaur known from the middle Early Cretaceous (Hauterivian or Barremian stage) of Iraq. Malawania was named by Valentin Fischer, Robert M. Appleby, Darren Naish, Jeff Liston, Riding, J. B., Brindley, S. and Pascal Godefroit in 2013 and the type species is Malawania anachronus.[1] It is unusual as it is much more primitive than other Cretaceous ichthyosaurs, being most closely related to Icthyosaurus itself from the Late Triassic and Early Jurassic, over 70 million years earlier, with all other known ichthyosaurs from the Late Jurassic onwards belonging to the family Ophthalmosauridae.

Malawania
Temporal range: Early Cretaceous, 132–125 Ma
Restoration
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Ichthyosauria
Family: Ichthyosauridae
Genus: Malawania
Fischer et al., 2013
Type species
Malawania anachronus
Fischer et al., 2013

Discovery

The holotype and only known specimen was discovered in 1952 by British petroleum geologists D. M. Morton, F. R. S. Henson, R. J. Wetzel and L. C. F. Damesin while working in Chia Gara, Armadia in Iraqi Kurdistan. The slab was being used to dam a small river and was part of a mule track. It was then transported back to the UK and donated to the Natural History Museum in 1959. Robert M. Appleby would study the specimen for many years until his death in 2004, but never published a paper, one manuscript submitted to Paleontology in 1979 was rejected due to the uncertain provenance of the specimen.[2] The specimen was formally described in 2013 by Fischer and colleagues. Using palynology it was determined that the rocks surrounding the specimen were Hauterivian-Barremian in age, which was unexpected given the archaic nature of the specimen.[1]

Taxonomy

The name is derived from "Kurdish ‘Malawan’: swimmer and Latinized Greek noun in apposition ‘anachronus’ meaning ‘out of time’."[1]

Phylogeny

Below is a cladogram modified from Fischer et. al., 2013.[1]

Mikadocephalus gracilirostris

 Parvipelvia 

Hudsonelpidia brevirostris

Macgowania janiceps

 Neoichthyosauria 

Temnodontosaurus

Leptonectes tenuirostris

Eurhinosaurus longirostris

Excalibosaurus costini

Suevoleviathan disinteger

Hauffiopteryx typicus

Thunnosauria 
 Ichthyosauridae 

Ichthyosaurus communis

Malawania anachronus

 Baracromia 

Stenopterygius quadriscissus

Chacaicosaurus cayi

 Ophthalmosauridae 

Arthropterygius chrisorum

 Ophthalmosaurinae 

Mollesaurus periallus

Ophthalmosaurus icenicus (type species)

Baptanodon natans ("O." natans)

Acamptonectes densus

 Platypterygiinae 

Brachypterygius extremus

Maiaspondylus lindoei

Aegirosaurus leptospondylus

Sveltonectes insolitus

"Platypterygius" hercynicus

Caypullisaurus bonapartei

Athabascasaurus bitumineus

"Platypterygius" australis

See also

References

  1. Fischer, V.; Appleby, R. M.; Naish, D.; Liston, J.; Riding, J. B.; Brindley, S.; Godefroit, P. (2013). "A basal thunnosaurian from Iraq reveals disparate phylogenetic origins for Cretaceous ichthyosaurs". Biology Letters. 9 (4): 20130021. doi:10.1098/rsbl.2013.0021. PMC 3730615. PMID 23676653.
  2. Naish, Darren. "Malawania from Iraq and the Cretaceous Ichthyosaur Revolution (part II)". Tetrapod Zoology. Scientific American. Retrieved 2020-07-27.


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