Notoryctemorphiamarsupial moles

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This order of metatherians contains two species, the marsupial moles (Notoryctes caurinus and Notoryctes typhlops; the status of N. caurinus has been questioned). Marsupial moles are astonishingly like eutherian golden moles (Insectivora, Chrysochloridae) in size and shape, and in the silky, irridescent texture and appearance of their fur. They have vestigial, functionally blind eyes that lack lens and pupil. They also have no external ears. Their snouts are covered by a horny shield, and their short and stout tails are also encased in leathery skin. The foreclaws are modified to be like miniature spades, with the third and fourth digits of the forefeet greatly enlarged and bearing enormous triangular claws. They do not appear to be syndactylous. The last five cervical vertebrae are fused, apparently to brace the neck when the animal pushes against the soil with its head. These animals "swim" through the soil, leaving no permanent burrow.

The teeth of the marsupial moles appear degenerate. They are neither fully polyprotodont nor diprotodont. The dental formula varies somewhat, but it is usually around 4-3/3, 1/1, 2/3, 4/4 = 40-44. The upper molars are zalambdodont, and the lower molars have lost their talonid basins.

Marsupial moles feed on invertebrate larvae. They are active day and night, and they often forage on the surface as well as beneath the ground.

The marsupium (pouch) is small but well developed.

The phylogenetic relationships of marsupial moles remain uncertain. Biochemically, they do not appear to be close to any other marsupial.


Literature and references cited

Aplin, K. P., and M. Archer. 1987. Recent advances in marsupial systematics with a new syncretic classification. Pp. xv-lxxii in Archer, M. (ed.), Possums and Opossums: Studies in Evolution, Vol. I. Surrey Beatty and Sons PTY Limited, Chipping Norton. lxxii+400 pp.

Feldhamer, G. A., L. C. Drickamer, S. H. Vessey, and J. F. Merritt. 1999. Mammalogy. Adaptation, Diversity, and Ecology. WCB McGraw-Hill, Boston. xii+563pp.

Marshall, L. G. 1984. Monotremes and marsupials. Pp 59-115 in Anderson, S. and J. Knox Jones, eds, Orders and Families of Recent Mammals of the World. John Wiley and Sons, NY. xii+686 pp.

Strahan, R. (ed.). 1995. Mammals of Australia. Smithsonian Institution Press, Washington, D.C. 756 pp.

Vaughan, T. A. 1986. Mammalogy. Third Edition. Saunders College Publishing, Fort Worth. vi+576 pp.

Vaughan, T. A., J. M. Ryan, N. J. Czaplewski. 2000. Mammalogy. Fourth Edition. Saunders College Publishing, Philadelphia. vii+565pp.

Wilson, D. E., and D. M. Reeder. 1993. Mammal Species of the World, A Taxonomic and Geographic Reference. 2nd edition. Smithsonian Institution Press, Washington. xviii+1206 pp.

Contributors

Phil Myers (author), Museum of Zoology, University of Michigan-Ann Arbor.

Glossary

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

motile

having the capacity to move from one place to another.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate