Thalpomys lasiotis (Winge, 1887)

Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Cricetidae, Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona: Lynx Edicions, pp. 204-535 : 468

541.

Hairy-eared Cerrado Mouse

Thalpomys lasiotis

French: Akodon a oreilles velues / German: Haarohr-Cerrado-Feldmaus / Spanish: Ratén del Cerrado de oeja peluda

Other common names: Hairy-eared Akodont

Taxonomy. Habrothrix lasiotis Winge, 1887 , Lagoa Santa, Minas Gerais, Brazil.

Thalpomys lasiotis is the type species of the genus. Monotypic.

Distribution. EC & SE Brazil ( Bahia , Minas Gerais, and Sao Paulo states, and Distrito Federal), with an isolated record in W Brazil (Rondonia State); range may extend to Matto Grosso State.

Descriptive notes. Head-body 76 mm (mean value for males), tail 46 mm, ear 13 mm, hindfoot 16 mm; weight 21 g. Males seem to be slightly larger than females. The Hairy-eared Cerrado Mouse is a smaller version of the Common Cerrado Mouse (1: cerradensis ) but with longer and more lax fur and more saturate color throughout. Chromosomal complement is 2n = 38, FN = 38.

Habitat. Open grasslands (“campo limpo”), open grasslands mixed with low shrubs (“campo cerrado”), open grasslands with scattered shrubs and trees (“campo sujo”), wet grasslands with water-saturated soil (“campo umido”), and wild grasslands with small natural earthen mounds without trees or underbrush (“campo de murundus”) in the Cerrado biome. The Hairy-eared Cerrado Mouse seems to have a patchy distribution occurring in higher densities in seasonally flooded habitats like campos de murundus.

Food and Feeding. The Hairy-eared Cerrado Mouse is considered to be insectivorous— omnivorous due to the high proportion of insect fragments found in its feces (70%). Weights of Hairy-eared Cerrado Mice vary little between seasons suggesting that diets also vary little seasonally.

Breeding. The Hairy-eared Cerrado Mouse apparently breeds differentially according to distribution; reproductive activity was recorded during wet season (November—February) in east-central Brazil but during end of dry season (August-October) in central Brazil. Overall, reproductive individuals occur in August—May. Litters have 2-3 young.

Activity patterns. The Hairy-eared Cerrado Mouse is nocturnal and terrestrial.

Movements, Home range and Social organization. Mean home range of 26 Hairy-eared Cerrado Mice (both sexes) was 2278 m?; home ranges of males and females did not different. No differences in distances moved between dry and rainy seasons (both sexes) and mean distance moved by males between seasons were found. Distances moved by two males were more than 1 km, suggesting important displacement in search of food, females, or territories. The Hairy-eared Cerrado Mouse had a residency of 2-9 months in natural habitats. Densities in winter were 0-5-0-6 ind/ha. The Hairy-eared Cerrado Mouse occurs in higher numbers during dry season, and higher population estimates and densities were observed in June-October. Higher density recorded during dry season seems to be related to availability of grass seeds.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Alho & Pereira (1985), Andrade et al. (2004), Bonvicino & Bezerra (2003), Dietz (1983), Hershkovitz (1990a), Lacher et al. (1990), Marinho-Filho, Bonvicino & Vieira (2008b), Pardinas & Teta (2015¢), Ribeiro & Marinho-Filho (2005), Ribeiro et al. (2011), Santos & Henriques (2010), Thomas (1916d), Vieira (1997).

Figures

523. Huanchaca Burrowing Mouse (Juscelinomys huanchacae), 524. Candango Burrowing Mouse (Juscelinomys candango), 525. Amazonian Hocicudo (Oxymycterus amazonicus), 526. Spy Hocicudo (Oxymycterus delator), 527. Atlantic Forest Hocicudo (Oxymycterus dosytrichos), 528. Quaestor Hocicudo (Oxymycterus quaestor), 529. Inca Hocicudo (Oxymycterus inca), 530. Paramo Hocicudo (Oxymycterus paramensis), 531. Elfin Forest Hocicudo (Oxymycterus nigrifrons), 532. Upper Yungas Inca Hocicudo (Oxymycterus juliacae), 533. Small Yungas Hocicudo (Oxymycterus hiska), 534. Quechuan Hocicudo (Oxymycterus hucucha), 535. Mount Caparao Hocicudo (Oxymycterus caparoae), 536. Red Hocicudo (Oxymycterus rufus), 537. Darwin’s Hocicudo (Oxymycterus nasutus), 538. Ravine Hocicudo (Oxymycterus wayku), 539. Cook’s Hocicudo (Oxymycterus joser), 540. Common Cerrado Mouse (Thalpomys cerradensis), 541. Hairy-eared Cerrado Mouse (Thalpomys lasiotis), 542. Roraima Mouse (Podoxymys roraimae), 543. Blackish Grass Mouse (Thaptomys nigrita), 544. Ecuadorean Akodont (Necromys punctulatus), 545. Northern Akodont (Necromys urichi), 546. Hairy-tailled Akodont (Necromys lasiurus), 547. Pleasant Akodont (Necromys amoenus), 548. White-chinned Akodont (Necromys lactens), 549. Lillo’s Akodont (Necromys lilloi), 550. Dark-furred Akodont (Necromys obscurus), 551. Kemp's Grass Mouse (Deltamys kempi), 552. Araucaria Grass Mouse (Deltamys araucaria), 553. Serra do Mar Grass Mouse (Castoria angustidens)

Distribution. EC & SE Brazil ( Bahia , Minas Gerais, and Sao Paulo states, and Distrito Federal), with an isolated record in W Brazil (Rondonia State); range may extend to Matto Grosso State.