509.

Lagoa Santa Pink-lipped Mouse

Bibimys labiosus

French: Bibimys du Brésil / German: Lagoa-Santa-Pinknasenmaus / Spanish: Ratén de labios rosados de Lagoa Santa

Other common names: Lagoa Santa Akodont, Lagoa Santa Swollen-nosed Mouse, Large-lipped Crimson-nosed Rat

Taxonomy. Scapteromys labiosus Winge, 1887, Lagoa Santa region, Minas Gerais, Brazil.

Species of Bibimys are characterized by subtle morphological characteristics, typically minor differences in color and measurements, most untested using large samples. The few samples sequenced for cytochrome-b had very low genetic distances. B. chacoensis might be better ranked as subspecies of or directly subsumed under B. labiosus after additional taxonomic and molecular research is done. Monotypic.

Distribution. SE & S Brazil, from Minas Gerais to Rio Grande do Sul states.

Descriptive notes. Head—body 76-90 mm, tail 62-73 mm, ear 14-17 mm, hindfoot 20-23 mm; weight 23-26 g. The Lagoa Santa Pink-lipped Mouse is small species of Bibimys . Furis soft, long, and dense; dorsum is brownish, somewhat paler on sides; and underparts are whitish, with slate-gray bases on hair. Mystacial vibrissae are 2.2-5 cm long. Tail 1s well-haired, but hair does not conceal annulations; it is dark brown above and paler below. Skull is delicate, and gnathic process (a paired acute bony plate produced forward the anterior face of upper incisors) is conspicuous. Incisors are opisthodont, and molars are minute. Chromosomal complement is 2n = 70, FNa = 80.

Habitat. Mostly associated with Atlantic Interior Forest but also ecotone between it and Cerrado biome at elevations of 420-1000 m. Specific habitats of the [Lagoa Santa Pinklipped Mouse are poorly known because most records are from owl pellets; individuals have been trapped in secondary forests, disturbed forested habitats, and ecotone formations with dense understory.

Food and Feeding. Dental morphology of the [Lagoa Santa Pink-lipped Mouse suggests an omnivorous diet, with a tendency to eat mostly vegetation.

Breeding. No information.

Activity patterns. Trapping data suggest that the Lagoa Santa Pink-lipped Mouse is nocturnal. The species has been caught in pitfall traps, suggesting terrestrial habits.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Holocene extralimital records north and south of the current distribution of the Lagoa Santa Pink-lipped Mouse (in Piaui and Rio Grande do Sulstates) indicate that it has suffered recent regional contractions of its distrubtion.

Bibliography. Casado et al. (2006), D'Elia et al. (2005), Diério (2014), Geise et al. (2006), Goncalves, Oliveira et al. (2005), Grazzini, Rezini et al. (2015), Hadler et al. (2016), Massoia (1980a), Paglia et al. (1995), Winge (1887).