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Licensed Unlicensed Requires Authentication Published by De Gruyter September 19, 2019

Quantitative morphological characters of the skull suggest that Akodon oenos (Rodentia, Cricetidae, Sigmodontinae) is not a junior synonym of A. spegazzinii

J. Pablo Jayat, Pablo E. Ortiz, Agustina A. Ojeda, Agustina Novillo, Pablo Teta, Guillermo D’Elía and Ricardo A. Ojeda
From the journal Mammalia


Akodon oenos, a nominal form with type locality in northern Mendoza province, Argentina, has an intricate taxonomic history. Recently, it was considered a junior synonym of Akodon spegazzinii on the basis of morphological similarities of one individual captured in southern Mendoza with specimens belonging to the type series of A. oenos, plus the genetic similarity of that single specimen with representatives of A. spegazzinii. We compared specimens of the Akodon boliviensis species group recently captured in Mendoza with the type series of A. oenos and series of A. spegazzinii from northwestern Argentina. We conducted an analysis of molecular markers (cytochrome-b gene) and quantitative morphological studies (comparisons of skull measurements). Our results showed that: (1) all sequenced specimens of the A. boliviensis group from Mendoza form a monophyletic clade closely related to A. spegazzinii; (2) contrary to previous hypothesis, specimens of Akodon from Mendoza are morphologically distinctive in size and shape of the skull, from A. spegazzinii; and (3) within the A. boliviensis species group, specimens from Mendoza are distinctive. We argue that the synonymy of A. oenos under A. spegazzinii must await further studies, including molecular markers other than mitochondrial and samples of DNA sequences from topotypical specimens of A. oenos.


We thank the numerous assistants who helped us with the field work, especially G. Namen, D. Miotti, W. Villafañe (Almita) and R. González. We are indebted to all the curators of the mammal collections visited for allowing access to specimens under their care: R. Barquez and M. Díaz (CML), U. F. J. Pardiñas (CNP), F. Prevosti (CRILAR), and D. Romero (MMPMa). Special thanks to R. Harbord who kindly provided the photographs of the holotypes of Akodon puer caenosus, A. tucumanensis, A. spegazzinii and A. sylvanus. Support was provided by the Instituto de Ambiente de Montaña y Regiones Áridas, Universidad Nacional de Chilecito (UNdeC), the Instituto Superior de Correlación Geológica (CONICET and Universidad Nacional de Tucumán), the Cátedra de Paleontología of the Universidad Nacional de Tucumán, the Instituto de Ecología Regional, Laboratorio de Investigaciones Ecológicas de Las Yungas (Universidad Nacional de Tucumán) and the Grupo de Investigaciones de Biodiversidad (GIB), Instituto Argentino de Zonas Áridas (IADIZA). Financial support was provided by CONICET (PIP 11220150100258 CO to RAO) and FONDECYT 1180366 (to GD).


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Supplementary Material

The online version of this article offers supplementary material (

Received: 2019-04-05
Accepted: 2019-08-27
Published Online: 2019-09-19
Published in Print: 2020-03-26

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