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A quantitative review of European stenonoid horses

Published online by Cambridge University Press:  20 May 2016

M. T. Alberdi ,
E. Ortiz-Jaureguizar  and
J. L. Prado
M. T. Alberdi
Affiliation:
Departamento de Paleobiología, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal, 2, 28006 Madrid, Spain
E. Ortiz-Jaureguizar
Affiliation:
Departamento de Paleobiología, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal, 2, 28006 Madrid, Spain Laboratorio de Sistemática y Biología Evolutiva (LASBE), Museo de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina
J. L. Prado
Affiliation:
INCUAPA, Facultad Ciencias Sociales, UNC, Provincia de Buenos Aires, San Martin 3060, 7400 Olavarría, Argentina
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Abstract

The taxonomy of the European stenonoid horses is revised using multivariate statistical techniques in this paper. The objectives are: to identify the taxonomic status of this group; to revise the specific and subspecific diagnoses, and the valid taxa; and to analyze their paleoecology and evolution. We conclude that: 1) there are six species among the Plio-Pleistocene European stenonoids: Equus major Depéret, in Delafond and Depéret 1893, ex Boule; Equus livenzovensis Bajgusheva, 1978; Equus stenonis Cocchi, 1867; Equus senezensis Prat, 1964; Equus altidens von Reichenau, 1915; and Equus sussenbornensis Wüts, 1901; 2) There are seven subspecies, three of E. stenonis, two of E. senezensis, and two of E. altidens; 3) There are two monophyletic groups according to the “neighbor-joining method,” one composed of the middle-to-small-size species, and the other of the biggest ones; 4) There is a trend toward decreasing body size through time in stenonoid horses. This trend, that follows the inverse direction of Cope's rule, can be related to the climatic-environmental changes that occurred from the middle Villafranchian to the early Galerian; 5) Large stenonoids were recorded in the middle Villafranchian and were associated with open and dry habitats (steppes), whereas the small ones lived in more closed and wet habitats (savanna-mosaic, woodlands) from late Villafranchian to earliest Galerian.

Type
Research Article
Information
Journal of Paleontology , Volume 72 , Issue 2 , March 1998 , pp. 371 - 387
Copyright
Copyright © The Paleontological Society 

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