Mammals of the Cosigüina Peninsula of Nicaragua


Nicaragua’s Cosigüina Peninsula, located at the northwestern tip of the country, is one of the most poorly studied biotic regions in Central America. The peninsula has been
occupied for millennia because the climate of the region supported human habitation and because of its strategic position along the rich Pacific coast. The combination of long-term occupancy by humans and the cataclysmic eruptions of Volcán Cosigüina have produced a heavily impacted landscape. During the 1960s, the University of Kansas conducted multiyear field surveys of the terrestrial mammals on the peninsula and the adjacent mainland to quantify species diversity, relationships, abundances, habitat use, and reproduction. The mammalian fauna of the peninsula contains at least 39 species of terrestrial mammals, which includes 7 orders and 17 families. These include Didelphimorphia (2 species)—Didelphidae, 2; Chiroptera (22)—Emballonuridae, 2; Noctilionidae, 1; Mormoopidae, 1; Phyllostomidae, 12; Vespertilionidae, 3; Molossidae, 3; Carnivora (4)—Procyonidae, 1; Mustelidae, 1; Felidae, 2; Perissodactyla (1)—Tapiridae, 1; Artiodactyla (1)—Cervidae, 1; Rodentia (8)—Sciuridae, 1; Heteromyidae, 1; Muridae, 5; Dasyproctidae, 1; Lagomorpha (1)—Leporidae, 1. We provide new information on distributions, systematics, morphometrics, and natural history of the species of terrestrial mammals on the Cosigüina Peninsula, including a number of new records for the peninsula. We document that diversity and abundances of mammals can be substantial in a heavily impacted landscape. In comparison with five other mammalian faunas in Nicaragua, the Cosigüina fauna is most similar in size and diversity with those from elsewhere in the Pacific lowlands. The fauna from the Cordillera los Maribios, which is composed of the volcanic peaks along the eastern edge of the Pacific Lowlands, has the lowest number of species recorded for any of the six faunas with only 21 species recorded; however, this fauna may be under sampled or the unstable environments offered by these active volcanoes may not support a large or diverse mammalian fauna. The mammalian faunas from the remaining two physiographic regions of Nicaragua—Central Highlands and Atlantic Lowlands—have larger, more diverse faunas than that of the Cosigüina Peninsula and elsewhere in the Pacific lowlands. Three reserves in Nicaragua’s Sistema Nacional de Áreas Protegidas now protect more than one fourth of the peninsula.

The Xenarthrans of Nicaragua


The mammalian fauna of Nicaragua includes seven species in the order Xenarthra, including the brown-throated three-toed sloth (Bradypus variegatus) in the family
Bradypodidae, Hoffmann’s two-toed sloth (Choloepus hoffmanni) in the family Megalonychidae, the northern naked-tailed armadillo (Cabassous centralis) and nine-banded armadillo (Dasypus novemcinctus) in the family Dasypodidae, and the silky anteater (Cyclopes didactylus) and northern tamandua (Tamandua mexicana) in the family Myrmecophagidae. Additionally, the giant anteater (Myrmecophaga tridactyla) in the family Myrmecophagidae is (or was) certainly part of the fauna of Nicaragua but has yet to be documented there. Based on 133 xenarthran specimens available in museums and our observations, we herein review and provide new information on distributions, systematics, morphometrics, and natural history of these species in Nicaragua. Replacement of the milk dentition in Dasypus novemcinctus is described and illustrated, documenting the most common adult dental formula of i 0/0, c 0/0, p 7/7, m 1/1 = 32.

Los Xenarthra de Nicaragua. La fauna mamífera de Nicaragua incluye siete especies del orden Xenarthra, incluyendo el perezoso de tres dedos (Bradypus variegatus) en la familia Bradypodidae, el perezoso (Choloepus hoffmanni) en la familia Megalonychidae, el armadillo zopilote (Cabassous centralis) y el cusuco (Dasypus novemcinctus) en la familia Dasypodidae, y el tapacara (Cyclopes didactylus) y el oso hormiguero (Tamandua mexicana) en la familia Myrmecophagidae. Además, el oso caballo (Myrmecophaga tridactyla) en la familia Myrmecophagidae es (o fue) ciertamente parte de la fauna de Nicaragua pero todavía no ha sido documentado allá. Basados en 133 especímenes de Xenarthra disponibles en museos y nuestras observaciones, revisamos y proveemos información nueva sobre distribuciones, sistemática, morfométrica y la historia natural de estas especies en Nicaragua. El reemplazo de la dentición láctea en Dasypus novemcinctus se describe e ilustra, documentando la fórmula dental adulta más común de i 0/0, c 0/0, p 7/7, m 1/1 = 32.