Abstract
We have studied the incisor enamel microstructure ofChaetomys subspinosus and other possibly closely related caviomorph rodents.Chaetomys subspinosus lacks the important synapomorphy of the Octodontoidea, reactangular plate-like interprismatic matrix (IPM) in the portio interna (PI) of the incisor Schmelzmuster. Therefore its transfer from the Erethizontidae to the Echimyidae, as proposed by Patterson and Wood (Bull. Mus. Comp. Zool. 149, 371–543, 1982) based on retention of dP4, is contested. The parallel to acute angular IPM in the PI ofChaetomys and the Erethizontidae is a symplesiomorphy and does not indicate close relationship. Contrary to previous claims, a posterior carotid foramen is also retained inChaetomys. Chaetomys is characterized by an unusual thin enamel which is considered primitive after outgroup comparison. Therefore, it is proposed to leaveChaetomys in the monospecific erethizontid subfamily Chaetomyinae, until additional information on the species is available.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Literature Cited
Avila-Pires, D. G. de (1967). The type locality ofChaetomys subspinosus (Olfers, 1818) (Rodentia: Caviomorpha).Rev. Brasil. Biol. 27: 177–179.
Bugge, J. (1974a). The cephalic arterial system in insectivores, primates, rodents, and lagomorphs, with special reference to the systematic classification.Acta Anat. 87 Suppl. 62: 1–160.
Bugge, J. (1974b). The cephalic arteries of hystricomorph rodents.Symp. Zool. Soc. Lond. Symp. 34: 61–78.
Eisenberg, J. F. (1989).Mammals of the Neotropics. The Northern Neotropics 1, University of Chicago Press, Chicago.
Ellermann, J. R. (1940).The Families and Genera of Living Rodents. British Museum (Natural History), London, (Reprint, 1966).
Emmons, L. H., and Feer, F. (1990).Neotropical Rainforest Mammals, a Field Guide, University of Chicago Press, Chicago.
Grassé, P.-P. (1955),Traité de Zoologie 17,2,Mammifères, Masson, Paris.
Gray, J. E. (1843). Account of two new species of bats, a species of the family Hystricidae, and a newManis.Proc. Zool. Soc. Lond. 11: 20–22.
Koenigswald, W. v. (1980). Schmelzmuster und Morphologie in den Molaren der Arvicolidae (Rodentia).Abh. Senckenb. Naturf. Ges. 539: 1–129.
Koenigswald, W. v. (1988). Enamel modification in enlarged front teeth among mammals and the various possible reinforcements of the enamel.Mém. Mus. Natl. Hist. Nat. C 53: 148–165.
Koenigswald, W. v., and Pfretzschner, H. U. (1987). Hunter-Schreger-Bänder im Zahnschmelz von Säugetieren: Anordnung und Prismenverlauf.Zoomorphology 106: 329–338.
Koenigswald, W. v., and Pfretzschner, H. U. (1991). Biomechanics in the enamel of mammalian teeth. InConstructional Morphology and Biomechanics, N. Schmidt-Kittler and K. Vogel eds., pp. 113–125. Springer Verlag, Berlin-Heidelberg.
Korvenkontio, V. A. (1934). Mikroskopische Untersuchungen an Nagerincisiven unter Hinweis auf die Schmelzstruktur der Backenzähne.Ann. Zool. Soc. Zool.-Bot. Fenn. Vanamo 2: 1–274.
Lehner, J., and Plenk, H. (1936). Die Zähne. In:Handbuch der mikroskopischen Anatomie des Menschen 5/3, W. v. Möllendorff ed., pp. 447–708, Berlin.
Luckett, W. P. (1985), Superordinal and intraordinal affinities of rodents: Developmental evidence from the dentition and placentation. In:Evolutionary Relationships Among Rodents, W. P. Luckett and J.-L. Hartenberger, eds., pp. 227–276. Plenum Press, New York.
Martin, T. (1992). Schmelzmikrostruktur in den Inzisiven alt-und neuweltlicher hystricognather Nagetiere.Palaeovertebrata, Mém. extra 1–168.
Martin, T. (1993). Early rodent incisor enamel evolution: Phylogenetic implications.J. Mamm. Evol. 1: 227–254
Martin, T. (1994). African origin of caviomorph rodents is indicated by incisor enamel microstructure.Paleobiology 20: 5–13.
Miller, G. S., and Gidley, J. W. (1918). Synopsis of the supergeneric groups of rodents.J. Wash. Acad. Sci. 8: 431–448.
Nowak, R. M., and Paradiso, J. L. (1983).Walker's Mammals of the World, 4th ed., Johns Hopkins University Press, Baltimore.
Olfers, I. v. (1818). Bemerkungen zu Illiger's Ueberblick der Säugethiere, nach ihrer Vertheilung über die Welttheile, rücksichtlich der Südamerikanischen Arten (Species). From: Eschwege, W. C. v.: Journal von Brasilien, oder vermischte Nachrichten aus Brasilien, auf wissenschaftlichen Reisen gesammelt. In:Neue Bibliothek der wichtigsten Reisebeschreibungen zur Erweiterung der Erd-und Völkerkunde,15, F. J. Bertuch, ed., pp. 193–237, Verlag des Landes-Industrie-Comptoirs, Weimar.
Oliver, W. L. R., and Santos, I. B. (1991). Threatened endemic mammals of the Atlantic forest region of Southeast Brazil.Spec. Sci. Rep. Jersey Wildlife Preserv. Trust 4: 1–125.
Patterson, B., and Wood, A. E. (1982). Rodents from the Deseadan Oligocene of Bolivia and the relationships of the Caviomorpha.Bull. Mus. Comp. Zool. 149: 371–543.
Pfretzschner, H. U. (1988). Structural reinforcement and crack propagation in enamel.Mém. Mus. Natl. Hist. Nat. Paris C 53: 133–143.
Pfretzschner, H. U. (1994). Biomechanik der Schmelzmikrostruktur in den Backenzähnen von Großsäugern.Palaeontographica A (in press).
Sahni, A. (1980). SEM studies of Eocene and Siwalik rodent enamels.Geosci. J. 1/2: 21–30.
Sahni, A. (1985). Enamel structure of early mammals and its role in evaluating relationships among rodents. In:Evolutionary Relationships Among Rodents, W. P. Luckett and J.-L. Hartenberger, eds., pp. 133–150, Plenum Press, New York.
Sarich, V. M., and Cronin, J. E. (1980). South American mammal molecular systematies, evolutionary clocks, and continental drift. In:Evolutionary Biology of the New World Monkeys and Continental Drift, R. L. Ciochon and A. B. Chiarelli, eds., pp. 347–368, Plenum Press, New York.
Schroeder, H. E. (1987).Orale Strukturbiologie, Thieme Verlag, Stuttgart, New York.
Stehlin, H. G., and Schaub, S. (1951). Die Trigonodontie der simplicidentaten Nager.Schweizer paläont. Abh. 67: 1–385.
Tomes, J. (1850). On the structure of the dental tissues of the order Rodentia.Phil Trans. Roy. Soc. Lond. 1850: 529–567.
Wahlert, J. H. (1968). Variability of rodent incisor enamel as viewed in thin section, and the microstructure of the enamel in fossil and Recent rodent groups.Brev. Mus. Comp. Zool. 309: 1–18.
Wahlert, J. H. (1984). Hystricomorphs, the oldest branch of the Rodentia.Ann. N.Y. Acad. Sci. 435: 356–357.
Wahlert, J. H. (1989). The three types of incisor enamel in rodents. In:Papers of Fossil Rodents in Honour of Albert Elmer Wood, Science Series, C. C. Black and M. Dawson, eds., pp. 7–16, Los Angeles County Museum.
Wahlert, J. H., and Koenigswald, W. v. (1985). Specialized enamel in incisors of eomyid rodents.Am. Mus. Novitates 2832: 1–12.
Wied, Prinz Maximilian zu (1826).Beiträge zur Naturgeschichte von Brasilien 2, Abteilung Säugtiere, Weimar.
Wood, A. E., and Patterson, B. (1959). The rodents of the Deseadan Oligocene of Patagonia and the beginnings of South American rodent evolution.Bull. Mus. Comp. Zool. 120: 282–428.
Woods, C. A. (1993). Suborder Hystricognathi. In:Mammal Species of the World, D. E. Wilson and D. M. Reeder, eds., pp. 771–806, Smithonian Institution Press, Washington, DC, London.
Woods, C. A., and Hermanson, J. W. (1985). Myology of hystricognath rodents: An analysis of form, function, and phylogeny. In:Evolutionary Relationships Among Rodents, W. P. Luckett and J.-L. Hartenberger, eds., pp. 515–548, Plenum Press, New York.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Martin, T. On the systematic position ofChaetomys subspinosus (Rodentia: Caviomorpha) based on evidence from the incisor enamel microstructure. J Mammal Evol 2, 117–131 (1994). https://doi.org/10.1007/BF01464364
Issue Date:
DOI: https://doi.org/10.1007/BF01464364