Jaguar Panthera onca and puma Puma concolor are sympatric throughout the jaguar's distribution. Although several studies have focused on the interactions between these two predators, the ecological and behavioural factors that promote their coexistence remain unclear. The goal of this study was to identify those factors that facilitate the coexistence of these cats in a mosaic landscape in the Venezuelan llanos. The study was conducted from January 1996 until November 1998. Five jaguars and six pumas were captured and radio-collared. A high degree of spatial overlap was observed between jaguars and pumas, which may be related to the abundance and distribution of prey species. At a fine scale, there was little overlap of puma locations with jaguar locations. Both species were more active at night than during daytime, but seasonal differences were detected in the activity levels of these predators. Major segregation was found in food habits. Jaguars selected for large prey and pumas for medium-sized prey. Jaguars selected for capybara Hydrochaeris hydrochaeris and collared peccary Tayassu tajacu and consumed caiman Caiman crocodilus and white-tailed deer Odocoileus virginianus less than expected. Pumas selected just for collared peccary and also killed caiman less than expected. It is suggested that the abundance of medium-sized prey is an ecological factor that is facilitating the coexistence of jaguar and puma in the study area. Habitat heterogeneity may be another influential factor leading to the coexistence. Seasonal differences in activity levels probably reflect differences in the size and species of prey taken by these cats.

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Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.

suMMaRy. -The Central American River Turtle, Dermatemys mawii, the single remaining extant species of the formerly wide-spread primitive family Dermatemydidae, is restricted to the Atlantic drainages of southern Mexico, Belize, and Guatemala. This large, highly aquatic, and totally herbivorous freshwater turtle is severely threatened throughout its range. There are older accounts citing specimens over 20 kg and carapace length of 60 cm, but recent field studies have found few individuals in excess of 14 kg in Mexico or above 11 kg in Guatemala. The turtle's large size and highly palatable meat yield a high profit when the animals are sold at market. This has motivated hunters to overharvest many populations into extirpation. Although Dermatemys is consumed year-round, exploitation peaks during dry weather when low water levels facilitate capture. All forms of capture tend to select for larger size classes, thus not only reducing densities, but altering population structures, resulting in lower proportions of reproductively mature animals. The maturing cohort of smaller juveniles that remains is usually soon removed as well, resulting in unproductive populations in decline. Since Dermatemys is an herbivorous species and grows relatively fast, there is the possibility of raising this species in captivity or semicaptivity in polyculture systems with freshwater shrimp or ornamental fish. Even fast turtle growth rates would probably translate to a relatively slow cash return, suggesting that Dermatemys perhaps be a complementary species in a polyculture system. Where the capital and interest are sufficient, detailed and well-documented experiments testing the overall feasibility of these schemes are advised. However, captive propagation efforts should not distract critical funds and attention from the maintenance of wild stocks in their native habitats. Law enforcement is not the aswer to maintaining wild stocks, and habitat destruction by itself is not the problem-unless local people change their ways and stop eating or selling every Dermatemys they can, there is little chance of rehabilitating wild populations.