First record of Eastern Cloud Forest Rat Nephelomys nimbosus (Rodentia: Cricetidae) for Colombia

THERYA, 2018, Vol. 9 (1): 103-106 DOI: 10.12933/therya-18-431 ISSN 2007-3364 First record of Eastern Cloud Forest Rat Nephelomys nimbosus (Rodentia: Cricetidae) for Colombia Sebastian Bautista Plazas1, 2*, Abelardo Rodríguez Bolaños2 and Ronald Castellanos Florez2 Laboratorio Ecología de Bosques Tropicales y Primatologia, Universidad de los Andes, Carrera 1 No 18A 12. Bogotá 111711, Colombia. Email: (SB). 2 Laboratorio Biodiversidad de Alta Montaña, Universidad Distrital Francisco José de Caldas, Carrera 4 No 26B 54. Bogotá 111611, Colombia. Email: (AR), (RC). * Corresponding author 1 Currently, four species of Nephelomys (N. childi, N. maculiventer, N. meridiensis and N. pectoralis) are known from Colombia. Here we present the first records of a fifth species, the rare Eastern Cloud Forest rat N. nimbosus, previously considered endemic to Ecuador and so far recorded only at five localities in the forests of the Eastern Cordillera. Four individuals of N. nimbosus were captured with Sherman traps at National Natural Park Cueva de los Guacharos in Huila Department, southern Colombia. Individuals were captured at two locations, a subandine primary forest at 2,000 m and at small cave ‘Cueva de los Guacharos’, at 1,900 m. Individuals were identified as N. nimbosus according to the following characteristics: ventral patche of self - colored white hairs in the gular region, ventral pelage ochraceous yellow with a golden tone, medium head-body size between 122 to 140 mm, incisive foramina between 4.6 and 5.1 mm with lateral margins rounded, posterolateral palatal pits small to big shallow and simple, hourglass shaped interorbital region, with supraorbital margins rounded or squared and a thin and delicate face. These new records increase the known species distribution by 760 kilometers to the north and present the first record of the species in Colombia. This first record of N. nimbosus for Colombia potentially extends the species distribution for northeastern Ecuadorian Cordillera and southern Colombian Cordillera. These results show the need to continue with the collection of specimens in poorly known species as N. nimbosus and in poorly known areas in Colombia, such as montane forests. Actualmente, Colombia presenta cuatro especies del genero Nephelomys (N. childi, N. maculiventer, N. meridiensis y N. pectoralis), aquí presentamos una quinta especie, la poco conocida rata de bosques nublados Nephelomys nimbosus, anteriormente considerada endemica de Ecuador y hasta ahora reportada para cinco localidades en bosques de la Cordillera Oriental. Cuatro individuos de N. nimbosus fueron capturados mediante trampas Sherman en el Parque Nacional Natural Cueva de los Guacharos, en el departamento de Huila, Colombia. Los individuos fueron encontrados en dos localidades, un bosque primario subandino a 2,000 m de altitud, y en una pequeña caverna “Cueva de los Guacharos”, a 1,900 m de altitud. Los individuos pudieron ser identificados como N. nimbosus de acuerdo con las siguientes características: Parche ventral con pelos de color blanco en la región gular, pelaje ventral color amarillo ocre con un tono dorado, tamaño mediano, con una longitud entre la cabeza y el cuerpo de 122 to 140 mm; el foramen incisivo corto entre 4.6 y 5.1 mm con márgenes laterales redondeados, fosas palatales posterolaterales pequeñas a grandes, superficiales y simples; región interorbital en forma de reloj de arena, con márgenes supraorbitales redondeados o cuadrados, un rostro delgado y delicado. Estos nuevos ejemplares permiten aumentar la distribución de la especie por 760 kilómetros y presentar el primer registro de la especie para Colombia. Este primer registro de N. nimbosus para Colombia, extiende la distribución de la especie para el norte de la cordillera oriental de Ecuador y el sur de Colombia. Los resultados muestran la necesidad de continuar con la colecta de especímenes en los bosques montanos de áreas poco conocidas de Colombia. Key words: Andes; montane forest; small non flying mammals; Thomasomyini. © 2018 Asociación Mexicana de Mastozoología, www.mastozoologiamexicana.org Introduction Cloud forest rats belonging to genus Nephelomys (Cricetidae: Sigmodontinae) distribute in the Andes (900 to 3000 m); they can be found in wooded paramo, montane cloud and elfin forest ecosystems (Percequillo 2003, 2015). Species of genus Nephelomys are present in South America from Colombia to Bolivia, including costal Venezuela, extending to the Cordilleras of Panama and Costa Rica in Central America (Percequillo 2003, 2015; Prado and Pecrequillo 2013). Four of the thirteen species of the genus, N. childi, N. maculiventer, N. pectoralis and N. meridiensis are known from Colombia (Percequillo 2003, 2015; Solari et al. 2013; Ramirez-Chavez et al. 2016). Historically the species N. nimbosus (Anthony 1926) was considered endemic to Ecuador. It was known from five localities along the eastern slope of the Andes Cordillera, specifically two locations in the Napo Province (Baeza and Chaco Oyacachi River) and two in the Tungurahua Province (San Antonio, San Francisco; Percequillo 2003, 2015). Later, a new locality record at southeastern Ecuador (Tapichalaca, Zamora Chinchipe Province) was reported (Brito et al. 2015; Figure 1). Given the scarcity of records, the natural history of N. nimbosus is poorly known. Here we present the Colombian first record for N. nimbosus. Materials and methods Individuals were captured between February and August of 2014 as part of the first inventory of small non flying mammals for the Natural National Park Cueva de los Guacharos (PNNCG) located in the department of Huila, Colombia First record Nephelomys nimbosus Natural History, AMNH 67337; Anthony 1926; Percequillo 2003), and a specimen of this species from south eastern Ecuador deposited in the Ecuadorian Museum of Natural Sciences (DMMECN 1083; Brito et al. 2015). Also, specimens were compared with individuals of N. childi (MUD 876; MUD 876; MUD 880; MUD 887; MUD 889). Body and cranial measures were taken with a gauge ± 0.1 following the definitions of Voss (1988) and Patton et al. (2000). Results Figure 1. Recording localities of Nephelomys nimbosus in Ecuador and the new one in Colombia at Huila department. (1° 36.14’N, -76° 8.13’W). Capture survey consist in linear transects of Sherman traps placed on the ground, a total of 100 traps were active for 150 days, totalizing a trapping effort of 1,5000 traps night (Bautista et al. 2014). N. nimbosus individuals were captured at two of the five sampling localities. The first one was a subandine primary forest at 2000 m; this location presents a high canopy with lianas and palms; some of the most abundant species were plants of the genus Wettinia, Hyeronima, Alchornea, Miconia, and Inga (Prada and Stevenson 2010). The second trapping locality was ‘Cueva de los Guacharos’ at 1900 m, a small cave with no vegetation where nocturnal frugivore birds known as oilbirds (St (...truncated)