Hystricomorpha

Hystricomorpha Temporal range: Eocene–Recent PreЄ Є O S D C P T J K Pg N
Capybara
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Suborder:	Hystricomorpha Brandt 1855
Superfamilies
See text

The term Hystricomorpha (from Latin hystrix, "porcupine" and Greek morphē "form")^[1] has had many definitions throughout its history. In the broadest sense it refers to any rodent (except dipodoids) with a hystricomorphous zygomasseteric system. This includes the Hystricognathi, Ctenodactylidae, Anomaluridae, and Pedetidae. Molecular and morphological results suggest that the inclusion of the Anomaluridae and Pedetidae in Hystricomorpha may be suspect. Based on Carleton & Musser 2005, these two families are treated here as representing a distinct suborder Anomaluromorpha.

Classification

Skull of a capybara showing the enlarged infraorbital canal present in most members of the Hystricomorpha. This condition is termed hystricomorphy.

The modern definition of Hystricomorpha also known as Entodacrya or Ctenohystrica is a taxonomic hypothesis uniting the gundis with the hystricognath rodents.^[2] There is considerable morphological support for this relationship and strong molecular support. If true, this hypothesis renders the traditional view of Sciurognathi invalid as it becomes a paraphyletic group.

The hystricomorph rodents, or at least members of Caviomorpha, are sometimes regarded as non-rodents.^[3] Most molecular and genetic research however confirms the monophyly of rodents.^[4] Support for rodent polyphyly appears to be a product of long branch attraction.^[5]

Hystricomorph rodents appeared in South America in the early Oligocene,^[6] a continent which previously had metatherians, xenarthrans, and meridiungulates as the only resident non-flying mammals. They apparently arrived by rafting across the Atlantic from Africa. The same type of migration may have occurred with primates, which also appeared in South America before the Great American Interchange. All of this is still controversial, and new scientific discoveries on this subject are published regularly.

Families

The following list of families is based on the taxonomy of Marivaux et al. 2002 and Marivaux, Vianey-Liaud & Jaeger 2004 who subjected a number of early fossil rodents to parsimony analysis and recovered support for the Hystricomorpha or Entodacrya hypothesis. Their results rendered the suborder Sciuravida as defined by McKenna & Bell 1997 to be polyphyletic and invalid. The symbol "†" is used to indicate extinct groups.

• Suborder Hystricomorpha
  • Superfamily Ctenodactyloidea
    • Ctenodactylidae - gundis
    • †Tammquammyidae
    • Diatomyidae - Laotian Rock Rat
    • †Yuomyidae
    • †Chapattimyidae
  • Hystricognathiformes
    • †Tsaganomyidae
    • Hystricognathi - true hystricognaths
      • †"Baluchimyinae"
      • Hystricidae - Old World porcupines
      • Phiomorpha
        • †Myophiomyidae
        • †Diamantomyidae
        • †Phiomyidae
        • †Kenyamyidae
        • Petromuridae - Dassie Rat
        • Thryonomyidae - cane rats
        • Bathyergidae - blesmols
        • †Bathyergoididae
      • Caviomorpha - New World hystricognaths
        • Superfamily Erethizontoidea
          • Erethizontidae - New World porcupines
        • Superfamily Cavioidea
          • †Cephalomyidae
          • Dasyproctidae - agoutis and acouchis
          • Cuniculidae - pacas
          • †Eocardiidae
          • Dinomyidae - pacarana
          • Caviidae - cavies, capybaras and guinea pigs
        • Superfamily Octodontoidea
          • Octodontidae - degus and relatives
          • Ctenomyidae - tuco-tucos
          • Echimyidae - spiny rats
          • Myocastoridae - nutria
          • Capromyidae - hutias
          • †Heptaxodontidae - giant hutias
        • Superfamily Chinchilloidea
          • Chinchillidae - chinchillas and viscachas
          • †Neoepiblemidae
          • Abrocomidae - chinchilla rats

Notes

1. ^ "Hystricomorpha". Oxford Dictionaries. http://oxforddictionaries.com/definition/Hystricomorpha. Retrieved November 2011. 
2. ^ Carleton & Musser 2005
3. ^ Graur, Hide & Li 1991; D'Erchia et al. 1996; Reyes, Pesole & Saccone 2000
4. ^ Cao et al. 1994; Kuma & Miyata 1994; Sullivan & Swofford 1997; Robinson-Rechavi, Ponger & Mouchiroud 2000; Lin et al. 2002; Reyes et al. 2004
5. ^ Bergsten 2005
6. ^ Flynn et al. 2003

References

Bergsten, J. (2005). "A review of long-branch attraction". Cladistics 21 (2): 163-193. doi:10.1111/j.1096-0031.2005.00059.x. 

Brandt, J. F. (1855) (in German). Beitrage zur nahern Kenntniss der Saugethiere Russlands. 

Cao, Y.; Adachi, J.; Yano, T.; Hasegawa, M. (1994). "Phylogenetic place of guinea pigs: No support of the rodent-polyphyly hypothesis from maximum-likelihood analyses of multiple protein sequences". Molecular Biology and Evolution 11 (4): 593-604. http://mbe.oxfordjournals.org/content/11/4/593.full.pdf. 

Carleton, M. D.; Musser, G. G. (2005). "Order Rodentia". In Wilson, D. E.; Reeder, D. M.. Mammal Species of the World A Taxonomic and Geographic Reference. Baltimore: Johns Hopkins University Press. pp. 745–752. ISBN 978-0801882210. 

D'Erchia, A.; Gissi, C.; Pesole, G.; Saccone, C.; Arnason, U. (1996). "The guinea-pig is not a rodent". Nature 381 (6583): 597-600. doi:10.1038/381597a0. 

Flynn, J. J.; Wyss, A. R.; Croft, D. A.; Charrier, R. (2003). "The Tinguiririca Fauna, Chile: biochronology, paleoecology, biogeography, and a new earliest Oligocene South American Land Mammal ‘Age’". Palaeogeography, Palaeoclimatology, Palaeoecology (Elsevier) 195 (3-4): 229-259. doi:10.1016/S0031-0182(03)00360-2. ISSN 00310182. 

Graur, D.; Hide, W.; Li, W. (1991). "Is the guinea-pig a rodent?". Nature 351 (6328): 649-652. PMID 2052090. 

Kuma, K.; Miyata, T. (1994). "Mammalian phylogeny inferred from multiple protein data" (PDF). Japanese Journal of Genetics 69 (5): 555-66. PMID 7999372. http://www.jstage.jst.go.jp/article/jjg/69/5/555/_pdf. 

Lin, Y.-H.; McLenachan, P. A.; Gore, A. R.; Phillips, M. J.; Ota, R.; Hendy, M. D.; Penny, D. (2002). "Four new mitochondrial genomes and the increased stability of evolutionary trees of mammals from improved taxon sampling". Molecular Biology and Evolution 19 (12): 2060-2070. PMID 12446798. http://mbe.oxfordjournals.org/content/19/12/2060.full.pdf. 

Marivaux, L.; Vianey-Liaud, M.; Jaeger, J.-J. (2004). "High-level phylogeny of early Tertiary rodents: dental evidence". Zoological Journal of the Linnean Society 142 (1): 105-134. doi:10.1111/j.1096-3642.2004.00131.x. 

Marivaux, L.; Welcomme, J.-L.; Vianey-Liaud, M.; Jaeger, J.-J. (2002). "The role of Asia in the origin and diversification of hystricognathous rodents". Zoologica Scripta 31 (3): 225-239. doi:10.1046/j.1463-6409.2002.00074.x. 

McKenna, M. C.; Bell, S. K. (1997). Classification of Mammals Above the Species Level. New York: Columbia University Press. ISBN 0-231-11013-8. 

Reyes, A.; Pesole, G.; Saccone, C. (2000). "Long-branch attraction phenomenon and the impact of among-site rate variation on rodent phylogeny". Gene 259 (1-2): 177-187. doi:10.1016/S0378-1119(00)00438-8. PMID 11163975. 

Reyes, A.; Gissi, C.; Catzeflis, F.; Nevo, E.; Pesole, G., Saccone, C. (2004). "Congruent mammalian trees from mitochondrial and nuclear genes using Bayesian methods". Molecular Biology and Evolution 21 (2): 397-403. doi:10.1093/molbev/msh033. http://mbe.oxfordjournals.org/content/21/2/397.full.pdf. 

Robinson-Rechavi, M.; Ponger, L.; Mouchiroud, D. (2000). "Nuclear gene LCAT supports rodent monophyly". Molecular Biology and Evolution 17 (9): 1410-1412. ISSN 0737-4038. http://mbe.oxfordjournals.org/content/17/9/1410.full.pdf. 

Sullivan, J.; Swofford, D. L. (1997). "Are Guinea Pigs Rodents? The Importance of Adequate Models in Molecular Phylogenetics". Journal of Mammalian Evolution 4 (2): 77-86. doi:10.1023/A:1027314112438. ISSN 10647554. http://www.webpages.uidaho.edu/~jacks/GuineaPig.pdf.