Akodon polopi Jayat et al., 2010 is a senior subjective synomym of Akodon viridescens Braun et al., 2010

G. DELÍA; J. P. JAYAT; P. E. ORTIZ; J. SALAZAR-BRAVO; U. F. J. PARDIÑAS

ZOOTAXA

MAGNOLIA PRESS

Lugar: Auckland, Nueva Zelanda; Año: 2011 vol. 2744 p. 62 - 64

1175-5326

Two new taxa of species level were recently named for grass mice of the genus Akodon (Cricetidae, Sigmodontinae) from central Argentina: Akodon polopi Jayat, Ortiz, Salazar-Bravo, Pardiñas et D’Elía, 2010 and Akodon viridescens Braun, Mares, Coyner et Van Den Bussche, 2010. Several lines of evidence show that both taxa refer to the same biological species. Various morphologic characters enumerated by the two research teams for polopi and viridescens are coincident. The brownish coloration of the dorsal pelage, the chin with a small but distinguishable white patch, the tail of approximately 70% of head and body length, and the broad rostrum are among the diagnostic characters cited for both forms. Other additional characters mentioned in the diagnosis of only one of the nominal forms are also enumerated in the general description of the other. These include the size intermediate for the genus, the hour-glass shaped interorbital region with sharply squared posterior margins in older individuals, the anterior border of mesopterygoid fossa rounded with sides parallel or slightly diverging backward, and the parapterygoid fossae with straight and gradually divergent sides. Many additional features are mentioned for both nominal forms in their general descriptions. Specimens assigned to A. polopi and A. viridescens have the same karyotype: a 2n = 40 composed by 18 telo/acrocentric and one metacentric autosome pairs, a subacrocentric or telocentric X chromosome, and a meta/acrocentric Y chromosome. The specimen CNP 1501 from Pampa de Achala, Córdoba, Argentina was assigned to both taxa in their original descriptions. As both names refer to the same biological entity and are based on different holotypes they ought to be considered subjective synonyms. The name Akodon polopi was published in Zootaxa on March 24, 2010 while Akodon viridescens was published on the April 16, 2010 issue of the Journal of Mammalogy. Therefore, Akodon polopi has priority over Akodon viridescens, being the later a junior subjective synonym of Akodon polopi.