New records and geographic distribution extension of Neusticomys ferreirai and N. oyapocki (Rodentia, Sigmodontinae)

Abstract

Little is known about the genus Neusticomys , one of the most poorly represented sigmodontine rodents in scientifi c collections. In this report, we provide new records of Neusticomys ferrerai and N. oyapocki in the Brazilian Amazonia and discuss possible limits for their geographic distributions. Three individuals of N. ferreirai were recorded during three distinct survey events. The fi rst record extends the range of the species approximately 100 km westward, and the other two extend it approximately 1000 km northeastward. For N. oyapocki , our record extends the currently known range of the species approximately 300 km westward. All specimens were collected in primary forests by 60-liter pitfall traps. Considering our records of N. ferreirai and the ecoregions associated with them, we argue that the species range may extends north along the interfl uves Xingu-Tocantins and Madeira-Tapaj ó s and west to the Guapor é River. Similarly, the limits of the range of N. oyapocki may coincide with the Amazon river at south, the Negro river at west and the transition zones between the Guianan forests and savannas or coastal vegetation at east and north. Larger series of Neusticomys in collections are expected to be available in the future, as more inventories using pitfall traps are carried out in Amazonia.

How many species of mammals are there in Brazil? New records of rare rodents (Rodentia: Cricetidae: Sigmodontinae) from Amazonia raise the current known diversity

“…All specimens recorded here were sampled with pitfall traps. Two of the three recently specimens of R. longilingua reported by Medina et al (2017) were captured with pitfall traps, as well as the recently reported specimens of genus Neusticomys ( Percequillo, Carmignotto & Silva, 2005 ; Leite, Silva & Da Gardner, 2007 ; Miranda et al, 2012 ; Braga & Duda, 2017 ). Therefore, we emphasize that surveys using pitfall traps are essential for the capture of these rodents, once again reinforcing the importance of this methodology on the study of Neotropical rodents (see Voss & Emmons, 1996 ; Abreu-Júnior et al, 2016 ; Abreu-Júnior, Brennand & Percequillo, 2017 ).…”

A new species of fish-eating rat, genus Neusticomys (Sigmodontinae), from Ecuador

“…Ichthyomyini is the least studied tribe of sigmodontine rodents; studies on these mice are rare in the literature, limiting in the current century to the reporting of new geographic records (e.g., Leite et al 2007;Miranda et al 2012;Nunes 2002;Pacheco and Ugarte-Núñez 2011), the presentation of new data in reports of mammalian surveys (e.g., Lee et al 2006aLee et al , 2006bLee et al , 2008Voss et al 2001), synthesis of available knowledge for one species (Packer and Lee 2007), and the description of a new species (e.g., Percequillo et al 2005). As such, aside from Voss (1988) study, no comprehensive phylogenetic hypothesis is available for the tribe.…”

Diversidad y estado de conservación de pequeños mamíferos de Loreto, Perú

“…Aunque las identificaciones pueden ser confiables para ciertas especies, sobre todo para equímidos y ardillas, puede ser más compleja en el caso de los pequeños mamíferos como roedores cricétidos o marsupiales; por lo que, este método debe considerarse como complemento a las técnicas convencionales (uso de trampas de captura viva y trampas de golpe) para obtener una mejor información de la diversidad de especies e incluir a especialistas en de estos grupos para una mejor aproximación en cuanto a las identificaciones. Además, es prioritario incorporar el uso de trampas de caída (pitfall) en los monitoreos porque han demostrado su eficacia para la colecta de pequeños mamíferos con hábitos terrestres y semiacuáticos en los bosques Neotropicales (Umetso et al 2006, Ribeiro-Junior et al 2011, Miranda et al 2012, Pacheco et al 2020b).…”