MEAD, J.I.; SWIFT, S.L.; WHITE, R.S. MCDONALD, H.G.; BAEZ, A. 2007. Late Pleistocene (Rancholabrean) Glyptodont and Pampathere (Xenarthra, Cingulata) from Sonora, Mexico. Revista Mexicana de Ciências Geológicas 24(3):439-449.
Abstract. The fossil-rich deposits of Térapa (east-central Sonora) contain more than 60 zoological taxa, many with tropical affinities such as Crocodylus (crocodylian), Hydrochaeris (capybara), and many birds. The deposits also contain the dermal ossicles (osteoderms) of two extinct xenarthrans, a glyptodont (Glyptotherium cylindricum) and a pampathere (giant armadillo; Pampatherium cf. mexicanum). Glyptodont remains are also known from other less-well studied localities in Sonora. The faunas from these localities also contain the genus Bison, which indicates that the deposits are of the Rancholabrean Land Mammal Age, late Pleistocene. The presence of Pampatherium at Térapa and the presence of Glyptotherium at Térapa and the Río Mayo/Río Yaqui sites represent the first published accounts of these species from Sonora, and greatly extends their known geographical distribution during the Rancholabrean by about 1,100 km into northwestern Mexico.
Mostrando postagens com marcador Cingulata. Mostrar todas as postagens
Mostrando postagens com marcador Cingulata. Mostrar todas as postagens
sábado, 10 de maio de 2014
sábado, 19 de abril de 2014
First records of the southern naked-tailed armadillo Cabassous unicinctus (Cingulata: Dasypodidae) in Paraguay
SMITH, P.; OWEN, R.D.; ATKINSON, K.; CASTILLO, H.; NORTHCOTE-SMITH, E. 2011. First records of the southern naked-tailed armadillo Cabassous unicinctus (Cingulata: Dasypodidae) in Paraguay. Edentata 12:53-57.
Abstract. The first specimens of southern naked-tailed armadillo Cabassous unicinctus squamicaudis from Paraguay are documented, extending the know distribution of the species approximately 270 km south-southwestward in the cerrado eco-region. This is the 12th spcies of armadillo documented as present in Paraguay. Paraguay is the only country with three representatives of the genus Cabassous occurring within its borders.
Abstract. The first specimens of southern naked-tailed armadillo Cabassous unicinctus squamicaudis from Paraguay are documented, extending the know distribution of the species approximately 270 km south-southwestward in the cerrado eco-region. This is the 12th spcies of armadillo documented as present in Paraguay. Paraguay is the only country with three representatives of the genus Cabassous occurring within its borders.
sábado, 5 de abril de 2014
The burrows of Dasypus hybridus Cingulata: Dasypodidae)
GONZÁLEZ, E.M.; SOUTULLO, A.; ALTUNA, C.A. 2001. The burrows of Dasypus hybridus Cingulata: Dasypodidae). Acta Theriologica 46(1):53-59.
Abstract. Dasypus hybridus (Desmarest, 1804) inhabits open fields in southern South America. Burrows of D. hybridus were cylindrical with a conical end. They had an entrance and a single tunnel without branches. Three locations of the burrows in the terrain were detected: in banks of dried waterways, near rocks, and in open field. The orientation of 29 burrow mouths was not random and, although they did not point to any cardinal point, in particular there was a strong tendency to avoid the south quadrant. In a sample area of 90 x 140 m, burrow mouths were arranged in a random spatial pattern with a density of 25.4 burrows por ha. Great variation in burrow length was found (118.8 +/- 105.69 cm, CV = 89.0%). Tunnels may be used as refuges and/or for thermo-regulation. The orientation of burrow mouths can also be related to thermoregulation as tunnels are covered from dominant winds, and, for many hours every day, the temperature at the mouths can be influenced by insolation. The possible existence of shelter-burrows and resting-burrows is discussed.
Abstract. Dasypus hybridus (Desmarest, 1804) inhabits open fields in southern South America. Burrows of D. hybridus were cylindrical with a conical end. They had an entrance and a single tunnel without branches. Three locations of the burrows in the terrain were detected: in banks of dried waterways, near rocks, and in open field. The orientation of 29 burrow mouths was not random and, although they did not point to any cardinal point, in particular there was a strong tendency to avoid the south quadrant. In a sample area of 90 x 140 m, burrow mouths were arranged in a random spatial pattern with a density of 25.4 burrows por ha. Great variation in burrow length was found (118.8 +/- 105.69 cm, CV = 89.0%). Tunnels may be used as refuges and/or for thermo-regulation. The orientation of burrow mouths can also be related to thermoregulation as tunnels are covered from dominant winds, and, for many hours every day, the temperature at the mouths can be influenced by insolation. The possible existence of shelter-burrows and resting-burrows is discussed.
sábado, 4 de maio de 2013
Anomalous color in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora)
ABREU, M.S.L.; MACHADO, R.; BARBIERI, F.; FREITAS, N.S.; OLIVEIRA, L.R. 2013. Anomalous color in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora). Brazilian Journal of Biology 73(1):185-194.
Abstract. Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp.) in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis) with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.
Abstract. Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp.) in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis) with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.
quarta-feira, 5 de outubro de 2011
Fotos: Dasypus novemcinctus
Espécie: Dasypus novemcinctus (tatu-galinha, armadillo de nueve bandas, nine-banded armadillo).
Fotógrafo: Maury S.L. Abreu
Contato: maury.abreu@gmail.com
sábado, 23 de julho de 2011
Effects of fire on the abundance of xenarthrans in Mato Grosso, Brazil
PRADA, M.; MARINHO-FILHO, J. 2004. Effects of fire on the abundance of xenarthrans in Mato Grosso, Brazil. Austral Ecology 29:568-593.
Abstract. Fire is an important ecological factor in Cerrado vegetation of central Brazil, and in other savanna
Abstract. Fire is an important ecological factor in Cerrado vegetation of central Brazil, and in other savanna
ecosystems. The effect of fire on the abundance of some Xenarthran mammal species Priodontes maximus
Kerr, 1792 (giant armadillo), Euphractus sexcinctus Linnaeus, 1758 (yellow armadillo) and Myrmecophaga tridactyla Linnaeus, 1758 (giant anteater)) was studied at Reserva Xavante do Rio das Mortes, a 329 000 ha Xavante Indian reserve in the Cerrado of Mato Grosso, Brazil. Track counts were used to compare the abundance of these mammals along seven burned and seven unburned transects, on seven occasions between August 1995 and August 1996. The number of tracks in burned and unburned areas did not differ. Xenarthrans probably use burned areas to obtain food resources, basically termites and ants. Xavante traditional fire hunts may reduce fuel accumulation and function as a mechanism to prevent more destructive fires. Fire management at Reserva Xavante is recommended because the burning system of Brazilian farmers is already influencing the Xavante community. Xavante traditional knowledge about fire could be an important instrument for this management.
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