DEFINITION AND DIAGNOSIS OF A NEW TRIBE OF SIGMODONTINE

GUILLERMO D'ELÍA; ULYSES F. J. PARDIÑAS; PABLO TETA; JAMES L. PATTON

GAYANA (CONCEPCIóN)

Universidad de Concepción

Lugar: Concepción; Año: 2007 vol. 71 p. 187 - 194

0717-652X

A new tribe of sigmodontine rodents is formally defined and diagnosed. The tribe contains the extant genera AbrothrixAbrothrix (including Chroeomys), Chelemys, Geoxus, Pearsonomys, and Notiomys, a group of taxa distributed in the central and southern Andes and lowlands both east and west of the cordillera. The new tribe presents a unique combination of characters including nasals and premaxilla usually projected anterior to the incisors, moderately trumpeted; zygomatic plate with upper free border reduced or obsolete; and third upper molar reduced and sub-cylindrical in out-line with an internal ring-like enamel fossette. Molecular phylogenetic analyses indicate that Abrothrix is sister to a clade containing the remaining genera of the new tribe.Chroeomys), Chelemys, Geoxus, Pearsonomys, and Notiomys, a group of taxa distributed in the central and southern Andes and lowlands both east and west of the cordillera. The new tribe presents a unique combination of characters including nasals and premaxilla usually projected anterior to the incisors, moderately trumpeted; zygomatic plate with upper free border reduced or obsolete; and third upper molar reduced and sub-cylindrical in out-line with an internal ring-like enamel fossette. Molecular phylogenetic analyses indicate that Abrothrix is sister to a clade containing the remaining genera of the new tribe.Abrothrix is sister to a clade containing the remaining genera of the new tribe.