Didelphis Marsupialis Research Articles

Coexistence of native and invasive species: the case of the Critically Endangered endemic carnivores from Cozumel Island, Mexico

ABSTRACT Species face increasing threats from anthropogenic disturbances to natural habitats, and we need to understand how threatened species are affected. For example, studying animals’ behavior and responses toward co-occurring species provides information on ecological interactions. We explored the patterns and drivers of the spatial use of two native carnivores endemic to Cozumel Island, Mexico, the Cozumel raccoon (Critically Endangered) and the dwarf coati (considered as Threatened in Mexico). We used multi-seasonal occupancy models to assess the effect that environmental variables, or the interactions with the other endemic carnivore, with a potentially competing species (common opossum) and with an invasive predator (dog), have on the activity of each endemic carnivore. We also compared their daily activity patterns. Habitat type was the main factor driving the detection and occupancy probability of both native carnivores that showed low to moderate overlap in daily activity patterns with competing species and with an invasive predator. Neither habitat disturbance nor dogs affected carnivore occupancy, suggesting that both variables have not reached a critical threshold to negatively influence the occurrence of native carnivores. Our results are relevant for understanding the spatiotemporal ecological requirements and constraints of two endangered endemic carnivores and for planning actions for their conservation.

Richness and distribution of New World marsupials (Didelphimorphia: Didelphidae) in the state of Piauí, Brazil

ABSTRACT Many gaps remain in understanding species evolution and distribution in Northeast Brazil, particularly in the Caatinga and Cerrado biomes. Our aims are to increase knowledge about the species of New World marsupials in the state of Piauí, identifying regions that are still poorly sampled, contributing to the delimitation of the geographic range of these species. We compiled online database data collection, scientific collection vouchers information and data from published articles. Twelve didelphid species were registred: Caluromys philander, Cryptonanus agricolai, Didelphis albiventris, Didelphis marsupialis, Gracilinanus agilis, Marmosa murina, Marmosa demerarae, Marmosops sp. Metachirus myosuros, Monodelphis domestica, Philander opossum, and Thylamys karimii. These represent about 18% of the Didelphidae occurring in Brazil. The survey revealed occurrences for 33 Piauí municipalities, representing only 12% of the state area. The extreme south and north of Piauí lack studies concerning marsupials, and parts of the centre-north and southeast are also poorly sampled. The results show an important geographic range increase for four species. Despite these results, Piauí is still an understudied region of the country. Valuable and immeasurable information may be lost due to degradation and loss of natural areas of Cerrado and Caatinga in the state.

Recording potential predators of herpetofauna in southern Mexico using camera traps and realistic models

ABSTRACT Knowledge of biotic predator–prey interactions is essential for understanding the role of species in the food web; however, information on these interactions is scarce for most species. Our aim in this study was to gather information on the potential predators of two species of herpetofauna abundant in the rainforest they inhabit, the frog Craugastor loki and the snake Ninia sebae. For this, realistic models of the two species were placed, and monitored using camera traps, in 13 sites located in a forest fragment belonging to a private protected natural area in southern Veracruz in three seasons (dry, rainy and windy) in 2019. In addition, the temporality and seasonality of the events and some behaviours of the potential predators are described. The recorded events were classified into four categories: presence, interest, contact and aggression. For C. loki, 159 events of appearances of potential predators were identified (32 with interaction: 18 events of interest, 2 contact and 12 aggressions). The aggressions were carried out by the mammals Didelphis marsupialis and Peromyscus sp. In the case of N. sebae, 201 appearances of potential predators were identified (75 with interaction: 36 events of interest, 7 contact and 32 aggressions). The aggressions were carried out by 10 species (seven birds and three mammals). Bird predation events towards models of both species occurred during daytime while the attacks by mammals occurred at night. Agonistic behaviours included pecking, biting and urine marking, previously unknown. Events of each category were recorded every season. Our results indicate that C. loki and N. sebae may have more predators than were previously known, and suggest that these species can be an important food resource for different species of birds and mammals in the environments where they live.

Parasites Diversity, Abundance, Prevalence, and Richness Infecting Didelphis aurita (Didelphimorphia: Didelphidae) in the Atlantic Rainforest, Brazil.

Parasites are key players in ecosystems, influencing population sizes and food webs, yet the impact of environmental factors on their diversity is not well understood. The Atlantic rainforest in Brazil, particularly the Parque Estadual das Fontes do Ipiranga (PEFI), exemplifies a biodiversity hotspot facing significant deforestation, housing diverse animal species such as the synanthropic Brazilian common opossum (Didelphis aurita), which serves as a reservoir for multiple zoonotic pathogens. In this study, we investigated parasite diversity, abundance, prevalence, and richness in free-living D. aurita in the PEFI, São Paulo, Brazil. From January 2015 to January 2017, 101 fecal samples of D. aurita were collected in two areas of PEFI, at the Instituto de Pesquisas Ambientais (IPA) and the Parque de Ciência e Tecnologia (Cientec), and analyzed using three different parasitological methods. In total, 99% of the samples were positive for at least one parasite. The most prevalent parasite belonged to the order Strongylida (82%), followed by Cruzia sp. (77%), the latter having a significantly higher prevalence at IPA. In contrast, Acanthocephala showed greater prevalence at Cientec. Co-infections were common, with some individuals harboring up to seven different parasites. Our findings reveal significant parasite diversity in the D. aurita population at PEFI, including both helminths and protozoan trophozoites, some of which are reported for the first time in this host species. Further research is essential for accurate species identification of the observed parasites.

Diversity and spatial genetic structure of the common opossum (Didelphis marsupialis) in an urban matrix of Northwestern Colombia

The common opossum (Didelphis marsupialis) is a marsupial widely distributed in the Neotropics, where it lives in urbanized environments. The apparent scarcity and fragmentation of available habitat, and high rates of vehicle collisions, may represent barriers to dispersal. To assess the functional connectivity of this species and its potential use as a model in urban ecology, we evaluated the structure and genetic diversity of opossums in the metropolitan area of the Aburrá Valley (AMVA), Colombia, using sequences of the mitochondrial Cytochrome B (Cytb) gene and nine autosomal microsatellite loci. Although Cytb presented low levels of variation, microsatellite markers revealed high genetic diversity (He = 0.852 and Ho = 0.698). The geographic distribution of mitochondrial lineages and a spatial principal component analysis (sPCA) of microsatellites showed the absence of genetic structure and effective barriers to dispersal of opossums in the study area. This scenario suggests that hostile landscapes such as those in urban environments may be suitable enough to allow the effective connectivity of some species such as the common opossum and others with high dispersal ability in urbanized areas. Nonetheless, it is necessary to evaluate the impact of releases of rescued fauna made by the environmental authority on the population structure of urban opossums.

Multilocus genetic analysis of Trypanosoma cruzi supports non-domestic intrusion into domestic transmission in an endemic region of Colombia

Trypanosoma cruzi, the causative agent of Chagas disease, is primarily transmitted to humans by hematophagous bugs of the Triatominae subfamily. In the Colombian Caribbean region, particularly on Margarita Island, T. cruzi transmission is highly endemic and associated with vectors such as Triatoma maculata and Rhodnius pallescens. Additionally, T. cruzi-infected Didelphis marsupialis are commonly found in close proximity to human dwellings. Given the complex transmission dynamics involving various domestic and non-domestic hosts, this study aimed to analyze 145 T. cruzi clones from twelve strains isolated from T. maculata, R. pallescens, and D. marsupialis using spliced leader intergenic region (SL-IR) sequences and nine polymorphic microsatellite loci. The results indicate the presence of a single polymorphic T. cruzi population, suggesting sustained local transmission dynamics between triatomines adapted to A. butyracea forests and peridomestic areas inhabited by synanthropic mammal reservoir such as D. marsupialis. Notably, this population appears to lack substructure, highlighting the importance of adopting an alternative eco-health approach to complement traditional chemical vector control methods for more effective and sustainable interruption of transmission.

Exploring the interplay between small and large scales movements in a neotropical small mammal

We record and analyze the movement patterns of the marsupial Didelphis aurita at different temporal scales. Animals trajectories are collected at a daily scale by using spool-and-line techniques and, with the help of radio-tracking devices, animals traveled distances are estimated at intervals of weeks. Small-scale movements are well described by truncated Lévy flight, while large-scale movements produce a distribution of distances which is compatible with a Brownian motion. A model of the movement behavior of these animals, based on a truncated Lévy flight calibrated on the small scale data, converges towards a Brownian behavior after a short time interval of the order of 1 week. These results show that whether Lévy flight or Brownian motion behaviors apply, will depend on the scale of aggregation of the animals paths. In this specific case, as the effect of the rude truncation present in the daily data generates a fast convergence towards Brownian behaviors, Lévy flights become of scarce interest for describing the local dispersion properties of these animals, which result well approximated by a normal diffusion process and not a fast, anomalous one. Interestingly, we are able to describe two movement phases as the consequence of a statistical effect generated by aggregation, without the necessity of introducing ecological constraints or mechanisms operating at different spatio-temporal scales. This result is of general interest, as it can be a key element for describing movement phenomenology at distinct spatio-temporal scales across different taxa and in a variety of systems.

Tail use behavior to carry vegetable matter by Marmosops incanus (Lund, 1840) and Didelphis aurita (Wied-Neuwied, 1826) (Didelphimorphia: Didelphidae)

This study describes Marmosops incanus and Didelphis aurita using their tails to carry plant material, probably for nesting. This is the first record of this behavior for M. incanus and for the tribe Thylamyini. Such description shows that this behavior is widespread amongst didelphid marsupials, indicating that this is a possibly ancestral behavior that remains in the group’s living species. Also, our record coincides with previous descriptions of M. incanus reproductive time, showing the importance of using video recording as a tool to understand the behavior of wild animals.

Transmission ecology of Trypanosoma cruzi by Rhodnius prolixus (Reduviidae: Triatominae) infesting palm-tree species in the Colombian Orinoco, indicates risks to human populations.

Chagas disease, affecting approximately eight million individuals in tropical regions, is primarily transmitted by vectors. Rhodnius prolixus, a triatomine vector, commonly inhabits in ecotopes with diverse palm tree species, creating optimal conditions for vector proliferation. This study aims to explore the transmission ecology of Trypanosoma cruzi, the causative parasite of Chagas disease, by investigating the feeding patterns and natural infection rates of R. prolixus specimens collected from various wild palm species in the Colombian Orinoco region. To achieve this objective, we sampled 35 individuals from three palm species (Attalea butyracea, Acrocomia aculeata, and Mauritia flexuosa) in a riparian forest in the Casanare department of eastern Colombia, totaling 105 sampled palm trees. DNA was extracted and analyzed from 115 R. prolixus specimens at different developmental stages using quantitative PCR (qPCR) for T. cruzi detection and identification of discrete typing units. Feeding preferences were determined by sequencing the 12S rRNA gene amplicon through next-generation sequencing. A total of 676 R. prolixus specimens were collected from the sampled palms. The study revealed variation in population densities and developmental stages of R. prolixus among palm tree species, with higher densities observed in A. butyracea and lower densities in M. flexuosa. TcI was the exclusive T. cruzi discrete typing unit (DTU) found, with infection frequency positively correlated with R. prolixus abundance. Insects captured in A. butyracea exhibited higher abundance and infection rates than those from other palm species. The feeding sources comprised 13 mammal species, showing no significant differences between palm species in terms of blood sources. However, Didelphis marsupialis and Homo sapiens were present in all examined R. prolixus, and Dasypus novemcinctus was found in 89.47% of the insects. This study highlights the significance of wild palms, particularly A. butyracea, as a substantial risk factor for T. cruzi transmission to humans in these environments. High population densities and infection rates of R. prolixus were observed in each examined palm tree species.

Detection and Genotyping of Trypanosoma cruzi Samples in Species of Genus Rhodnius from Different Environments in the Brazilian Amazon.

Background: In the Amazon region, several species of triatomines occur in the natural environments. Among them, species of the genus Rhodnius are a risk to human populations due to their high rates of infection with Trypanosoma cruzi. The aim of this study was to identify the T. cruzi genotypes in Rhodnius specimens and their relationship with sylvatic hosts from different environments in the Brazilian Amazon. Methods: A total of 492 triatomines were collected from the municipalities of Monte Negro, Rondônia state, and Humaitá, Amazonas state, 382 of them being nymphs and 110 adults. Genotyping of T. cruzi in six discrete typing units (DTUs) was performed using conventional multilocus PCR. The triatomines that were positive for T. cruzi and engorged with blood were also targeted for amplification of the cytochrome B (cytB) gene to identify bloodmeal sources. Results: Of the 162 positive samples, the identified DTUs were TcI (87.65%) and TcIV (12.35%). It was observed that 102 specimens were engorged with a variety of bloodmeals. Triatomines infected with TcI were associated with DNA of all identified vertebrates, except Plecturocebus brunneus. TcIV was detected in triatomines that fed on Coendou prehensilis, Didelphis marsupialis, Mabuya nigropunctata, P. brunneus, Pithecia irrorata, Sapajus apella, and Tamandua tetradactyla. Conclusion: Results highlight the need to understand the patterns of T. cruzi genotypes in Rhodnius spp. and their association with sylvatic hosts to better elucidate their role in the transmission of Chagas disease in the Amazon region.

Morphology and reproduction of the common opossum (Didelphis marsupialis) dwelling in urban vs rural environments in Antioquia, Colombia

Background: Urban wildlife has been increasing during the last years, however the effect of urbanization on it is poorly understood. The common opossum (Didelphis marsupialis) is very frequent in the Metropolitan Area of Valle del Aburrá (AMVA), in Antioquia, Colombia, where there is also a strong opossum-human conflict that results in a large number of injured/dead opossums. Objective: We evaluated the effects of urban and rural habitats on the morphometry and the reproductive output (litter size in marsupium) of opossums. Methods: A total of 131 opossums were captured, 94 from the AMVA, and 37 from rural areas of Antioquia. Opossums were weighed, measured, sexed, clinically inspected, and photographed. Results: Urban opossums were heavier and larger than rural individuals, regardless of sex, and there were no differences in the reproductive output between the two habitats. Also, urban opossums were more abundant than rural opossums. A potential explanation of these results is that cities favor survival mediated by higher food consumption, but not reproduction. Alternatively, bigger animals could also be explained by an inadequate food consumption rich on carbohydrates which may have potential negative health consequences. We confirmed the sexual size dimorphism of the common opossum in the head and tail lengths but not on the body length. Conclusion: We confirm a significant effect of urban environments on body mass and size of opossums; however, it is unknown whether it is beneficial or detrimental. Litter size is the lowest reported for the species, and there was no difference between rural and urban habitats.

Gastrointestinal parasites in common opossums (Didelphis marsupialis) of urban protected areas in Antioquia, Colombia

Background: The common opossum (Didelphis marsupialis) is a generalist species that hosts several parasites. Nevertheless, no information is available on the specific parasites that this species may host when it inhabits urban areas. Objective: To evaluate the presence and frequency of gastrointestinal parasites of urban opossums in the Aburrá Valley, Antioquia, Colombia. Methods: A total of 70 opossums were captured in six protected urban areas using Tomahawk traps during six months. From these animals we obtained 65 fecal samples which were fixed wit SAF solution and analyzed with direct smear and sedimentation techniques. Results: Sixty-one samples were positive for, at least, one parasite (93.9%) and 60 were positive for two or more parasites, averaging five parasites per animal. We observed nematodes in 58 samples (89.2%), protozoa in 46 samples (70.7%), acanthocephalans in 29 samples (44.6%), and cestodes in eight samples (12.3%). The most frequent parasite was Aspidodera spp. in 80% of the samples. In addition, this is the first study reporting the presence of eggs of Toxocara spp., Hymenolepis spp., an Oxyuridae parasite, and coccidians Eimeria didelphidis, E. caluromydis, and E. marmosopos in D. marsupialis. The latter is also reported in Colombia for the first time. Toxacara spp. is common to dogs and cats, while Hymenolepis and Oxiuridae are common to rodents. We found no association between parasites and sex or life stage of opossums, nor to the urban area of origin. Conclusions: Urban opossums in the Aburrá Valley host a high frequency and diversity of gastrointestinal parasites compared to other areas in Latin America. Some parasites are reported here for the first time.

The common black-eared opossum in the symbolic and iconographic universe. From the effigy ornaments in the lesser Antilles to the European graphics of Simivulpa and its variants in the 16th – 17th centuries

This study focuses on the aesthetic analysis, iconographic variants, and symbolism of the common black-eared opossum (Didelphis marsupialis Linnaeus 1758) in ceramic ornaments of agro-ceramic origin of the Saladoid tradition with Barrancoid influence, located in the south of the Lesser Antilles arc and Venezuela, currently held in different collections, scientific academies, and museums around the world, particularly in the Caribbean and United States. Likewise, it will study an entire corpus of prints with descriptions and illustrations of the marsupial, the latter being elaborated by European artists through wood engravings or etchings. For this purpose, chroniclers and artists often relied on the analogical outline of Aristotle, disarticulating the didelphidae into anatomic parts to later compare them with those of other animals according to their degree of similarity, usually being with species of the so-called Old World, in order to create a ‘new’ concept, in reality, an anomalous creature, resulting from the juxtaposition of images of the ‘old’ over the ‘new’, in order to show the intelligible and unknown of the Caribbean world in a way that is comprehensible and accessible to the human mind, with the objective of providing zoological continuity and closing the gaps that once separated both ‘worlds’, in other words, the semiosis of Charles Sanders Peirce.

The common black-eared opossum in the symbolic and iconographic universe. From the effigy ornaments in the lesser Antilles to the European graphics of Simivulpa and its variants in the 16th – 17th centuries

This study focuses on the aesthetic analysis, iconographic variants, and symbolism of the common black-eared opossum (Didelphis marsupialis Linnaeus 1758) in ceramic ornaments of agro-ceramic origin of the Saladoid tradition with Barrancoid influence, located in the south of the Lesser Antilles arc and Venezuela, currently held in different collections, scientific academies, and museums around the world, particularly in the Caribbean and United States. Likewise, it will study an entire corpus of prints with descriptions and illustrations of the marsupial, the latter being elaborated by European artists through wood engravings or etchings. For this purpose, chroniclers and artists often relied on the analogical outline of Aristotle, disarticulating the didelphidae into anatomic parts to later compare them with those of other animals according to their degree of similarity, usually being with species of the so-called Old World, in order to create a ‘new’ concept, in reality, an anomalous creature, resulting from the juxtaposition of images of the ‘old’ over the ‘new’, in order to show the intelligible and unknown of the Caribbean world in a way that is comprehensible and accessible to the human mind, with the objective of providing zoological continuity and closing the gaps that once separated both ‘worlds’, in other words, the semiosis of Charles Sanders Peirce.

Predation of the black-eared opossum (Didelphis aurita) on the great kiskadee (Pitangus sulphuratus) and the water rat (Nectomys squamipes)

Abstract Understanding the predatory behavior of a species is critical to its ecological role. Little is known about the predatory behavior of the marsupial Didelphis aurita. Here, we present two cases to shed light on its opportunistic nature: an opossum struggling to locate and attack an immobile juvenile bird, indicating olfactory detection and visual constraints, and an opossum carrying a weakened rat that was host of four blowfly larvae. These events reinforce D. aurita’s opportunistic behavior in attacking debilitated vertebrates.

The effect of El Niño and La Niña episodes on the existing niche and potential distribution of vector and host species of American Cutaneous Leishmaniasis

Leishmaniasis is a zoonotic disease transmitted to humans by a protozoan parasite through sandfly vectors and multiple vertebrate hosts. The Pan American Health Organization reported a declining trend in cases, with Brazil, Colombia, Peru, Nicaragua, and Bolivia having the most cases in 2020. There are still knowledge gaps in transmission and the parasite-host relationship. Ecological niche modeling has been used to study host-vector relationships, disease dynamics, and the impact of climate change. Understanding these aspects can aid in early surveillance and vector control strategies. The potential distribution of five host species associated with the transmission of cutaneous leishmaniasis (CL) was modeled. Occurrence data were collected for each host species, and environmental variables were used to build the models. Climatic data from El Niño, La Niña, and Neutral episodes were used to compare the predicted distributions. Additionally, the potential distributions of four vector species were compared to identify overlaps with host species. Niche analysis was conducted to evaluate changes in vector niches across episodes and to identify host-vector pairs based on niche overlap in geographic and environmental spaces. After spatial thinning, 467 records were obtained, and 1,190 candidate models were evaluated for each species. Results showed the distribution of occurrences in the environmental space, highlighting a high risk of extrapolation beyond the calibration areas. Movement-Oriented Parity analysis revealed distinct distribution patterns under different climate conditions, with areas of environmental similarity identified. Bradypus variegatus exhibited a broad potential distribution, while Dasypus novemcinctus and Didelphis marsupialis had more restricted ranges. Sylvilagus braziliensis covered most of the Neotropics. Our study provides valuable insights into ecological niches and geographic ranges of these species, contributing to the understanding of cutaneous leishmaniasis transmission dynamics.

Potential distribution of marsupials (Didelphimorphia: Didelphidae) in Mexico under 2 climate change scenarios

Abstract Climate change is one of the main threats to biodiversity in the 21st century. However, the effects that it may have on different mammal species are unknown, making it difficult to implement conservation strategies. In this paper, we used species distribution models (SDM) to assess the effect of global climate change on the potential distribution of the 8 of the 9 marsupial species in Mexico, and analyzed their distribution in the current system of natural protected areas (NPAs). We used presence records for each species and bioclimatic variables from the present and the future (2050 and 2080) with 2 contrasting possible scenarios (representative concentration pathways RCP 4.5 and 8.5). We found that Tlacuatzin canescens would have the most stable potential range under any climate change scenario, while the remaining species (Caluromys derbianus, Chironectes minimus, Didelphis marsupialis, D. virginiana, Philander opossum, Marmosa mexicana, and Metachirus nudicaudatus) would undergo notable range losses in the future, though there would not only be losses—according to our SDMs, for all species there would be some range gain under the different climate scenarios, assuming the vegetation cover remained. The current system of NPAs in Mexico currently protects and under the 2 future scenarios would protect less than 20% of the potential range of marsupials, so a reevaluation of their areas beyond the NPAs is highly recommended for the long-term conservation of this group. Our results provide relevant information on the estimated effects of global climate change on marsupials, allowing us to design more effective methodologies for the protection of this portion of the mammalian fauna in Mexico.

Molecular detection of piroplasmids in mammals from the Superorder Xenarthra in Brazil.

Xenarthra mammals can be found from southern North America to southern South America, including all Brazilian biomes. Although it has been shown that Xenarthra mammals can play a role as reservoirs for several zoonotic agents, few studies investigate the diversity of piroplasmids (Apicomplexa: Piroplasmida) in this group of mammals. Taking into account that piroplasmids can cause disease in animals and humans, understanding the prevalence and diversity of piroplasmids in Xenarthra mammals would contribute to conservation efforts for this group of animals as well as to infer risk areas for transmission of emergent zoonosis. The present study aimed to investigate the occurrence and molecular identity of piroplasmids in free-living mammals of the Superorder Xenarthra from four Brazilian states (Mato Grosso do Sul, São Paulo, Rondônia, and Pará). For this, DNA was extracted from blood or spleen samples from 455 animals. A nested PCR based on the 18S rRNA gene was used as screening for piroplasmids. Of the 455 samples analyzed, 25 (5.5%) were positive. Additionally, PCR assays based on 18S rRNA near-complete, cox-1, cox-3, hsp70, cytB, β-tubulin genes and the ITS-1 intergenic region were performed. Five out of 25 positive samples also tested positive for ITS-1-based PCR. The phylogenetic analysis positioned three 18S rRNA sequences detected in Priodontes maximus into the same clade of Babesia sp. detected in marsupials (Didelphis albiventris, Didelphis marsupialis, and Monodelphis domestica) and Amblyomma dubitatum collected from opossums and coatis in Brazil. On the other hand, the 18S rRNA sequence obtained from Dasypus novemcinctus was closely related to a Theileria sp. sequence previously detected in armadillos from Mato Grosso State, grouping in a subclade within the Theileria sensu stricto clade. In the phylogenetic analysis based on the ITS-1 region, the sequences obtained from Myrmecophaga tridactyla and Tamandua tetradactyla were placed into a single clade, apart from the other piroplasmid clades. The present study demonstrated the molecular occurrence of Piroplasmida in anteaters and Babesia sp. and Theileria sp. in armadillos from Brazil.

Variation of mammal diversity along a gradient separated by geographic barriers within the Andes of Perú

The protection of many mammal species is restrained by anthropogenic pressures. For this reason, using camera traps is critical to learning about the characteristics of their populations and communities, especially when geographic barriers limit their dispersal. This study aimed to measure the variation in mammal diversity in three areas under different protection levels (Piñi Piñi, Manu Learning Centre, and Aguanos), separated by geographic barriers within the Manu Biosphere Reserve. Relative abundance indices, correspondence analysis, non-metric multidimensional scaling, diversity analysis using Hill numbers, similarity analysis, and Bray-Curtis beta diversity partitioning were measured with the recorded data. Overall, 193 individuals of 36 species were recorded, some showing area preference. Didelphis marsupialis, Dicotyles tajacu, and Sylvilagus brasiliensis prefer areas with a lower protection level. According to Hill's diversity indices, the most diverse area is the Manu Learning Centre. The three areas show variations in diversity due to changes in their composition (balanced variation) influenced by geographic barriers, such as Cerro Teparo Punta and the Alto Madre de Dios River.

Philander opossum as prey of Didelphis marsupialis in a rainforest in México

Las selvas húmedas Neotropicales albergan una diversidad de mamíferos con interacciones complejas entre especies. Los didélfidos, conocidos como tlacuaches, son mamíferos comunes en estas selvas húmedas. En México, el tlacuache común, Didelphis marsupialis y el tlacuache cuatro ojos, Philander opossum son especies simpátricas en estas selvas. La zona de estudio se localiza en una selva tropical húmeda de la Estación de Biología Los Tuxtlas, en Veracruz, México. Se filmaron ambas especies de tlacuaches in situ usando un teléfono celular. Las características morfológicas de ambas especies corresponden a individuos adultos de D. marsupialis y P. opossum. El video muestra a un individuo de D. marsupialis cruzando una vereda y llevando en su hocico un cadáver, como presa, de un individuo de P. opossum. Se documenta el primer reporte de P. opossum como presa de D. marsupialis en una selva tropical húmeda en México. Se discute si este escenario ocurrió por un evento de depredación, o bien, por un encuentro fortuito con una carcasa que estaba siendo trasladada para su consumo. Se conoce que D. marsupialis consume carcasas, aunque también caza otras especies de tlacuaches. Nuestro estudio coincide con observaciones que documentan la depredación de D. marsupialis sobre P. opossum en Barro Colorado, Panamá y contribuye a proveer información relevante sobre los hábitos alimenticios de esta especie en selvas tropicales húmedas.