<p>Se describe una nueva especie de marsupial perteneciente al complejo <italic>parvidens</italic> del género <italic>Marmosops</italic> a partir de material proveniente de la Cordillera de la Costa Central y Andes de Venezuela. Los caracteres diagnósticos que diferencian a este nuevo taxón del resto de sus congéneres, incluyen un tubérculo carpal pequeño en los machos, con forma de triángulo; mano con almohadilla tenar prominente con respecto al tubérculo carpal; almohadilla hipotenar pequeña y desplazada hacia el ápice de la palma respecto a la tenar; caninos superiores con sólo las cúspides accesorias posteriores, tanto en machos como hembras; forámenes lagrimales dentro de la órbita y orientados hacia la región anterior de ésta; forámenes palatinos posterolaterales grandes y alcanzando el protocono del cuarto molar superior; hueso maxilar no cubriendo completamente la región posterior del cuarto molar superior; cuarto molar inferior con dos cúspides sobre el talónido. Se añade información de historia natural y se discute la distribución actual de las restantes especies de <italic>Marmosops</italic> del grupo <italic>parvidens</italic> en Venezuela.</p>
<sec sec-type="intro"><title>INTRODUCTION:</title><p>Within the genus <italic>Marmosops</italic> 17 species are currently recognized. Recent treatment of what has been recognized as the <italic>Marmosops</italic> parvidens group involves the recognition of five species<italic>: M. parvidens, M. pinheiroi</italic> [including <italic>woodalli</italic>], <italic>M. bishopi, M. juninensis, and M. pakaraimae</italic>. The two former and the last species occurs in Venezuela, being the identity of the single record of <italic>M. parvidens</italic> north of the Orinoco river placed in doubt by most recent authors.</p></sec><sec sec-type="methods"><title>METHODS:</title><p>External measurements were taken from museum labels; craniodental measurements were taken with a caliper to the nearest 0.01mm. Geographic coordinates of relevant localities were taken from literature and altitudes from museum labels. Reviewed specimens (Apendix) are housed in: Museo de la Estación Biológica de Rancho Grande (EBRG, Aragua, Venezuela), Museo de Historia Natural La Salle (MHNLS, Distrito Capital, Venezuela), Museo de Zoología de la Universidad de Carabobo (MZUC, Carabobo, Venezuela) and Colecão Zoológica de Mastozoología, Universidad Federal de Mato Grosso (UFMT, Cuiabá, Mato Grosso, Brazil). Relevant characters of taxa unavailable to us were taken from literature.</p></sec><sec sec-type="results"><title>RESULTS:</title><p>Recently additional material assignable to <italic>Marmosops parvidens</italic> from northern Venezuela was analyzed. Closer examination of these specimens led to the description of a new species herein proposed, which is clearly distinguished from other species of the group by a unique combination of characters, among them, a triangle-shaped carpal tubercle in males; posterior accessory cusps on the upper canines in males and females; maxilla not completely covering the fourth upper molar, and fourth lower molar bicuspid (<xref ref-type="table" rid="t2">Table 2</xref>; <xref ref-type="fig" rid="f2">Fig. 2</xref>, <xref ref-type="fig" rid="f3"><sup>3</sup></xref>, <xref ref-type="fig" rid="f4"><sup>4</sup></xref> and <xref ref-type="fig" rid="f5"><sup>5</sup></xref>). Known distribution embraces the Cordillera de la Costa Central and Cordillera de Mérida in Venezuela (<xref ref-type="fig" rid="f1">Fig. 1</xref>), with an elevation span of 50 to 1850 m a.s.l.</p></sec><sec sec-type="conclusions"><title>DISCUSSION AND CONCLUSIONS:</title><p>Before the recognition of <italic>Marmosops pinheiroi</italic> as a distinct species, many authors accepted the presence of <italic>M. p. parvidens</italic> in northern Venezuela and south of the river Orinoco (Amazonas) and <italic>M. p. pinheiroi</italic> in the south (Bolívar, Canaima National Park). More recently, the presence of <italic>parvidens</italic> was referred to the north and south of Venezuela and in sympatry with <italic>M. pinheiroi</italic> at Canaima National Park. However, examination of the specimens of <italic>Marmosops</italic> housed in Venezuelan natural history museums indicates that <italic>M. parvidens</italic> is not present in Venezuela (pending the confirmation of the identity of a single specimen from northern Venezuela housed in Washington). Equally, literature records might be misleading (e. g. the sympatry of <italic>M. parvidens and M. pinheiroi</italic> at Canaima National Park). So far, records of the new species indicate it is restricted to the mountain ranges of northern and western Venezuela.</p></sec>