Small mammals from the Seasonally Dry Tropical Forests of the Huallaga river basin and new records for San Martín department, Peru

Abstract

The Seasonally Dry Tropical Forests in Peru are well known for their bird and plant diversity and endemicity, but little is known about the diversity of small mammals. We report the diversity of small volant and non-volant mammals from the Seasonally Dry Tropical Forests of the Huallaga river basin in the San Martín Department, working on both sides of the river, making a sampling effort of 3060 traps-night for non-volant and 104 mist nets-night for volant mammals. We recorded 29 species, including five marsupials, three rodents, and 21 bats. Among the bats, phyllostomids were the most diverse group with 16 species. Short-tailed Spiny-rat, Proechimys brevicauda (Günther, 1877) and Seba's Short-tailed Bat, Carollia perspicillata (Linnaeus, 1758), featured the highest relative abundance. In addition, we report the first records for the San Martín Department of Peropteryx macrotis (Wagner, 1843), Saccopteryx bilineata (Temminck, 1838), Lonchorhina aurita Tomes, 1863, Vampyriscus bidens (Dobson, 1878), and Myotis simus Thomas, 1901. The species richness and diversity indices indicate the study site has a high diversity value; however, fragmentation and rapid changes in land-use are the main threats faced by the biodiversity of these dry forests.

Systematic Revision of Thomasomys cinereus (Rodentia: Cricetidae: Sigmodontinae) from Northern Peru and Southern Ecuador, With Descriptions of Three New Species

“…The Huancabamba Depression has been proposed as a barrier between northern and central Andean faunas because it is thought to limit the dispersion of species living at high elevation (Parker et al, 1985; Patterson et al, 1992; Pacheco and Patterson, 1992; Albuja and Patterson, 1996; Vivar et al, 1997; Duellman and Pramuk, 1999; Pacheco, 2002; Lunde and Pacheco, 2003). The habitat in the Huancabamba Depression is mostly open shrubby vegetation or dry forests (Linares-Palomino, 2004) that have a mammalian fauna resembling those of adjacent lowland forests (Ruelas and Pacheco, 2021b), Such habitats are not inhabited by species of Thomasomys (Pacheco, 2015) and—consistent with its hypothesized role as a dispersal barrier—the Huancabamba Depression appears to separate the distribution of T. lojapiuranus in the north from the distributions of the other three species in this complex ( T. cinereus , T. shallqukucha , and T. pagaibambensis ), which are all found to the south. Of the latter, T. shallqukucha and T. pagaibambensis are both distributed in the Cordillera Occidental, and no major river has previously been suggested as a potential barrier between the small ranges that they occupy.…”

Los bosques estacionalmente secos del Perú

“…Adicionalmente a estas características florísticas, estos bosques también contienen comunidades de aves únicas y diversas (Vásquez-Arévalo et al 2018) que confirman la definición de este subgrupo oriental. Sin embargo, estudios de las comunidades de mamíferos menores no encontraron especies endémicas o especialistas de BES y la mayoría de las especies registradas en los BES del Huallaga también ocurrieron en los bosques húmedos de llanura adyacentes (Ruelas & Pacheco 2021).…”