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Camera traps became the main observational method of a myriad of species over large areas. Data sets from camera traps can be used to describe the patterns and monitor the occupancy, abundance, and richness of wildlife, essential information for conservation in times of rapid climate and land-cover changes. Habitat loss and poaching are responsible for historical population losses of mammals in the Atlantic Forest biodiversity hotspot, especially for medium to large-sized species. Here we present a data set from camera trap surveys of medium to large-sized native mammals (>1 kg) across the Atlantic Forest. We compiled data from 5380 ground-level camera trap deployments in 3046 locations, from 2004 to 2020, resulting in 43,068 records of 58 species. These data add to existing data sets of mammals in the Atlantic Forest by including dates of camera operation needed for analyses dealing with imperfect detection. We also included, when available, information on important predictors of detection, namely the camera brand and model, use of bait, and obstruction of camera viewshed that can be measured from example pictures at each camera location. Besides its application in studies on the patterns and mechanisms behind occupancy, relative abundance, richness, and detection, the data set presented here can be used to study species' daily activity patterns, activity levels, and spatiotemporal interactions between species. Moreover, data can be used combined with other data sources in the multiple and expanding uses of integrated population modeling. An R script is available to view summaries of the data set. We expect that this data set will be used to advance the knowledge of mammal assemblages and to inform evidence-based solutions for the conservation of the Atlantic Forest. The data are not copyright restricted; please cite this paper when using the data., (© 2024 The Ecological Society of America.)

Long-term-ecological-research (LTER) faces many challenges, including the difficulty of obtaining long-term funding, changes in research questions and sampling designs, keeping researchers collecting standardized data for many years, impediments to interactions with local people, and the difficulty of integrating the needs of local decision makers with "big science". These issues result in a lack of universally accepted guidelines as to how research should be done and integrated among LTER sites. Here we discuss how the RAPELD (standardized field infrastructure system), can help deal with these issues as a complementary technique in LTER studies, allowing comparisons across landscapes and ecosystems and reducing sampling costs. RAPELD uses local surveys to understand broad spatial and temporal patterns while enhancing decision-making and training of researchers, local indigenous groups and traditional communities. Sampling of ecological data can be carried out by different researchers through standardized protocols, resulting in spatial data that can be used to answer temporal questions, and allow new questions to be investigated. Results can also be integrated into existing biodiversity networks. Integrated systems are the most efficient way to save resources, maximize results, and accumulate information that can be used in the face of the unknown unknowns upon which our future depends.

Bats harbor diverse groups of ectoparasites, such as insects and mites like ticks (Ixodida). Some species of ticks with records for bats and humans have already been reported with the occurrence of pathogens. This research article aims to document new geographical and host records of ticks infesting bats in Rio de Janeiro state, Southeastern Brazil, and provides a list of tick species associated with bats in Brazil. We counted 12 argasid ticks and five ixodid ticks associated with six individuals of bats. Larvae of Amblyomma sp., Ixodes sp., Ornithodoros sp., and Ornithodoros hasei and one nymph of Amblyomma sculptum parasitizing Artibeus obscurus, Phyllostomus hastatus, Micronycteris sp., Molossus fluminensis, and Carollia perspicillata in different localities of Rio de Janeiro state were studied. We carried out a systematic review with the descriptors: tick bat Brazil. We considered data from 42 articles in the systematic review. We compiled eleven records of Ixodidae, and 160 records of Argasidae. Ornithodoros cavernicolous were the most recorded tick species. Overall, we registered 171 tick-bat or roost-bat associations with 85 records of these infesting bats. The review also shows the occurrence of tick species associated with bats, and we present new records on ticks parasitizing bats in Brazil., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The native marmoset of the Southeastern Atlantic Forest in Brazil is among the 25 most endangered primates of the world. Hybridization with alien species is one of its main threats registered since the early 2000s based on phenotype, so far, without genetic confirmation. Using uniparental molecular markers, we analyzed 18 putative hybrids, captured from 2004 to 2013 in different localities of the Atlantic Forest. A nine base pair deletion in the SRY gene of C. aurita was used to investigate paternal ancestry. Maternal ancestry was assessed by DNA sequencing of ca. 455 bp from the COX2 gene. Hybridization was confirmed for 16 out of the 18 marmosets since they inherited COX2 haplotypes of the alien C. penicillata or C. jacchus and the SRY deletion specific to C. aurita. Two individuals inherited both parental lineages of C. aurita, which is probably related to backcrossing or hybrid interbreeding. The direction of hybridization of females with the matrilineal lineage of invasive species with males descending from the native lineage was predominant in our sampling. This is the first time that hybridization between C. aurita and invasive species has been confirmed through genetic analysis., (© 2022. The Author(s).)

Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called "restinga" and "campo nativo" habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data., (© 2020 The Authors. Ecology © 2020 The Ecological Society of America.)

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data., (© 2020 The Authors. Ecology © 2020 The Ecological Society of America.)

Introduction: A new coccidian species of the genus Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae), is reported from the bat host Myotis riparius Handley from Ilha Grande, a large island off the coast of the State of Rio de Janeiro, in southeastern Brazil., Methods: Bats were captured in 13 mist nets (10 × 3 m), which were set within the experimental plots, and through active searches of the daytime roosts of Molossus molossus Pallas found in Vila Dois Rios. Containment was made in bags for the collection of feces and identification of coccidia. A survey was conducted on the coccidia species described so far (Table 2)., Results: The oöcysts of Eimeria riparii n. sp. are ellipsoidal to cylindroidal with an extremely thin, bi-layered wall, slightly rough. Two polar granules are present, micropyle and oöcyst residuum are both absent. The sporocysts are ellipsoidal, the sporocyst residuum is formed by sparse, rounded granules of varying sizes; the Stieda body is trapezoidal and a sub-Stieda body is absent. Sporozoites are banana shaped. With the new species described here, a total of 40 Eimeria spp. have been described infecting bat hosts, belonging to 30 species of 18 genera and 5 families., Conclusion: The subsequent increase in the known diversity of bats has been derived from the ongoing expansion of research in a number of different areas of taxonomy and ecology although the number of studies of the associated coccidian parasites of the family Eimeriidae has increased more slowly.

We investigated the spatial distribution of native and invasive marmoset species (Callithrix), as well as their hybrids, in the Serra dos Órgãos National Park (PARNASO) and surrounding area in Rio de Janeiro state, Brazil. To estimate occupancy and the detection probability, we surveyed 56 sites within the park and 52 sites outside its limits using vocal playbacks, as well as by interviewing local residents in the surrounding area. We estimated the occupancy and detection probability of Callithrix aurita and the observed groups composed of Callithrix jacchus, Callithrix penicillata, and their hybrids. We also recorded the presence or absence of mixed groups of native and exotic species, and their hybrids. We recorded similar occupancy rates and detection probabilities for both native and invasive species within the national park. C. aurita was found more often within the areas of the park located furthest from access roads and with the least human interference, while invasive species were more likely to be found along the edge of the park and in areas with greater human interference. In the area surrounding the park, invasive marmosets were recorded at seven sites, and a mixed group of native and invasive marmosets was observed at one site, but non-hybrid C. aurita groups were not recorded. The occupancy probability of C. aurita in the study area is relatively low, which may indicate a low population density, with groups restricted to a small region within the PARNASO in the proximity of groups of invasive marmosets., (© 2017 Wiley Periodicals, Inc.)

Local abundance results from the interaction between populational and environmental processes. The abundance of the species in a community is also one of the most basic descriptors of its structure. Despite its importance, information about species abundances is fragmentary, creating a knowledge gap about species abundances known as the Prestonian Shortfall. Here we present a comprehensive data set of small mammal abundance in the Atlantic Forest. Data were extracted from 114 published sources and from unpublished data collected by our research groups spanning from 1943 to 2017. The data set includes 1,902 records of at least 111 species in 155 localities, totaling 42,617 individuals represented. We selected studies that (1) were conducted in forested habitats of the Atlantic Forest, (2) had a minimum sampling effort of at least 500 trap-nights, and (3) contained species abundance data in detail. For each study, we recorded (1) latitude and longitude, (2) name of the locality, (3) employed sampling effort, (4) type of traps used, (5) study year, (6) country, and (7) species name with (8) its respective abundances. For every locality, we also obtained information regarding its (9) ecoregion, (10) predominant vegetation type, and (11) biogeographic subdivision. Whenever necessary, we also (12) updated the species names as new species were described and some genera suffered taxonomic revision since the publication. The localities are spread across the Atlantic Forest and most of the small mammal species known to occur in Atlantic Forest are present in the data set, making it representative of communities of the entire biome. This data set can be used to address various patterns in community ecology and geographical ecology, as the relation between local abundance and environmental suitability, hypothesis regarding local and regional factors on community structuring, species abundance distributions (SAD), functional and phylogenetic mechanisms on community assembling., (© 2017 by the Ecological Society of America.)

The head morphology and feeding habits of pairs of characin species (family Characidae) that coexist in four different coastal rainforest streams were analysed. Coexisting species differed in size, but were very similar in eco-morphological attributes. Gut analyses revealed differences in feeding preferences for each coexisting species, indicating resource partitioning. A pattern of organization in species pairs that was repeated in the four studied streams was noticed. The pattern consisted of one slightly larger species with a feeding preference for items of allochthonous origin and another smaller species with a preference for autochthonous items. The hypothesis that small morphological differences enable the current coexistence of those species pairs was proposed. Furthermore, the results show ecological equivalence among different species in the studied streams., (© 2016 The Fisheries Society of the British Isles.)

The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or "Canga", which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (<< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively affect sensitive wildlife species., Competing Interests: I declare, as coordinator-chief of the project “Monitoring of fauna of Carajás National Forest”, that the funding by UFRA-VALE Grant that finished on 2012 year, does not alter our adherence to PLOS ONE policies on sharing data and materials.

The gekkonid lizard Hemidactylus mabouia is an exotic species in Brazil and is found in different ecosystems. This species was recorded at Ilha Grande, RJ, one of the largest insular remains of the Atlantic Rainforest in Brazil. In this study, the occurrence of H. mabouia was determined throughout the island, including the rain forest, restinga and anthropic environments. We used the active search method in points along 19 trails that surround Ilha Grande. At each regular interval of 100 m, we searched for the presence of H. mabouia. The species was recorded in a total of 100 points among the 719 sampled and, in all cases, the occurrence of the lizard corresponded to points located in anthropic or perianthropic areas. As most of Ilha Grande is covered by dense tropical rain forest, we believe this has restricted the invasion of H. mabouia in natural environments within the island.

Host specificity is a characteristic property of parasite-host associations and often is high among those involving obligate or permanent parasites. While many parasites are highly host-specific under natural conditions, specificity may break down in the absence of dispersal barriers. We tested the host specificity of obligate and permanent blood-feeding bat parasites (Hemiptera: Polyctenidae) under experimental conditions where parasite dispersal barriers had been removed. Under these conditions, parasites not only readily accepted a secondary host species but also remained there when a primary host was immediately available. Experiments with bat bugs and observations of streblid bat flies suggest that specificity may at least temporarily break down when dispersal barriers are removed. To affect long-term coevolutionary patterns, such transfers would necessarily entail the establishment of viable parasite populations on secondary host species.

The Restinga de Jurubatiba has at least 10 plant formations, including open Clusia shrubland. This formation is composed of dense shrubs of many shapes and sizes, where Clusia hilariana is one of the most important plant species. Shrublands with Clusia (CC) are poorer in plant species and less dense than shrublands without Clusia (SC). Oryzomys subflavus (Rodentia) is the most abundant small mammal species in the open Clusia shrubland. We tested the hypothesis that the abundance of rodents would increase with the size of the patch and would be higher in SC shrublands. Rodents were captured, marked and released in three 780-m-long transects. At each capture site, we evaluated the shape of the shrubland patch, calculated the area and noted the category of the shrubland. Using ANCOVA, we ascertained whether the abundance of Oryzomys subflavus increased with the sampled area and used CC and SC shrublands differently. We also verified if the size of patches used by rodents varies in the same frequency as the size of available shrublands. Rodent abundance was found to increase significantly with the area. There were no differences in the size of the patches used by rodents and the frequency of the size of available patches. This finding indicates that O. subflavus, in the study area, is a generalist species that uses its habitat according to availability.

Host-choice experiments were carried out with rodent and bat ectoparasites on Ilha Grande, state of Rio de Janeiro, Brazil. We constructed experimental chambers that enclosed three different rodent or bat host species, and then introduced a selected set of ectoparasitic arthropods. When given the opportunity to choose among host species, the ectoparasites showed a strong tendency to select their primary hosts, and reject novel host species. These kinds of simple experiments can be valuable tools for assessing the ability of ectoparasites to locate and discern differences between host species, and make choices about which hosts to infest, and which hosts to avoid.

We analyzed the prevalence, intensity, and medium density of parasitism of Hesperoctenes fumarius infesting Molossus rufus in natural (hollow trees) and anthropogenic roosts (attics) in southeastern Brazil. The prevalence and intensity of infestations were higher in the hollow trees than in the attic roosts. We also noted a relationship between the amount of space available within the roost and the infestation levels of H. fumarius. One advantage of roosting in larger, often man-made, refuges may be the reduction in ectoparasite infestations.

Biodiversity corridors comprise a mosaic of land uses connecting fragments of natural forest across a landscape. Two such corridors have been established along the eastern coast of Brazil: the Serra do Mar and the Central da Mata Atlântica corridors, along which most of the coastal plains are restinga areas. In this study, we analyze the present status of the endemic and endangered terrestrial vertebrates of both corridors. We sampled 10 restingas in both corridors, recording species of amphibians, reptiles, birds, and mammals. Some restingas harbor a relatively large number of endemic species,and two main regions of endemism can be identified along the restingas of both corridors: the coastal restingas from northern Espirito Santo State to southern Bahia State (between Linhares, ES, and Tarancoso, BA), and the coastal region between the restingas of Maricá and Jurubatiba, Rio de Janeiro State. Six species of terrestrial vertebrates considered threatened with extinction are found in the restingas of Serra do Mar and Central da Mata Atlântica biodiversity corridors (Liolaemus lutzae, Formicivora littoralis, Mimus gilvus, Schistochlamys melanopis, and Trinomys eliasi). The region located between the restinga of Maricá and that of Jurubatiba is of special relevance for the conservation of vertebrate species of the restingas of the corridors because a considerable number of threatened species of terrestrial vertebrates are found there. We strongly recommend efforts to develop checklists of threatened faunas for the States of Espirito Santo and Bahia.

Itatiaia National Park (PNI) and its surroundings present a unique fauna due to different forest formations with well-defined climatic and vegetation bands. The Itatiaia massif has four vegetation types that follow an altitudinal gradient: lower montane forest, montane forest, upper montane forest, and Campos de Altitude. Hence, this region is ideal for studying geographical variation in biological diversity. The main objectives of this study were to report on nonvolant mammal species known to occur in Itatiaia National Park and its surroundings and to determine if their distributional pattern is related to elevation. A review of the literature and a complete survey of specimens deposited in museums, as well as small-mammal trapping were carried out in order to obtain a complete record of the species from the region. Precise locality data were obtained for all specimens recorded, allowing the inclusion of each collected or observed individual in an altitude and vegetational class. We made a direct ordination gradient of marsupial, primate, and rodent species abundance with the altitude. Sixty-nine mammal species were collected or reported for the Itatiaia massif, belonging to seven orders and 20 families. Of these, 33 species (47.8%) are included in the official list of threatened or believed-to-be threatened species in Rio de Janeiro State. The orders Rodentia, Carnivora, and Didelphimorphia had the highest species richness, with 25, 14, and 13 species respectively. When species were grouped according to the vegetation, 16 species occured in the lower montane, 56 in the montane forest, five in the upper montane, and 21 in the high-altitude fields (Campos de Altitude). The communities of marsupials, primates, and rodents have an ordination pattern related to the altitude. Species richness was higher between 500 m and 1,500 m above sea level in montane forest, which is in agreement with recent studies showing that species richness can reach its maximum at mid-elevations.

Tur megistoproctus, a new species of Laelapinae, is described from the pelage of the echimyid rodent Proechimys dimidiatus from the Atlantic forests of Ilha Grande, south of Rio de Janeiro. Measurements and illustrations are included for females and males. Another laelapine mite species, Tur turki Fonseca, co-occurred with T. megistoproctus in our studies and was recorded from the same host individuals and localities. These 2 laelapine mite species appear to be exclusively associated with a complex of echimyid rodent species (subgenus Trinomys) in the Atlantic forests of southeastern Brazil.

Mesostigmatic mites of the Laelapinae Berlese, 1892 (Acari: Laelapidae) are nidicolous arthropods that commonly occur in the fur of Neotropical small mammmals. In this 2-yr study, the laelapine acarofauna associated with the small mammal community in an area of Atlantic forest on Ilha Grande, Rio de Janeiro State, was examined, including observations on patterns of host specificity, mite dispersal, ecology, and food habits. A total of 1,347 laelapines was sampled from the pelage of 6 species of small mammals (Marmosops incanus, Nectomys squamipes, Oryzomys russatus, Rhipidomys n. sp., Oxymycterus dasytrichus, and Trinomys dimidiatus), all of which occurred exclusively in monoxenous associations with their hosts. No evidence of a blood meal was observed in the gut of the mites. With the exception of the 2 species of Tur, mite populations on hosts were entirely or nearly restricted to adult females. These results, together with some morphological characteristics of laelapines, reinforce the hypotheses that Neotropical laelapine mites are not ectoparasitic, and that females disperse by phoresy.

Androlaelaps marmosops, a new species of laelapid mite, is described from the pelage of the mouse opossum, Marmosops incanus (Lund, 1840) (Mammalia: Didelphidae), in two areas of Atlantic Forest of Rio de Janeiro State. Measurements and illustrations are included for females only.

The effect of defence force size in colonies of the ant Azteca muelleri on the time spent to localize, attack and expel the specialized herbivorous beetle Coelomera ruficornis from Cecropia pachystachya bushes was studied in an area of Atlantic forest in northeastern Brazil. Our results show that Azteca muelleri expel Coelomera ruficornis from Cecropia pachystachya and that the number of ants leaving a colony (defence force size) is negatively correlated with the residence time of an adult beetle on the plant. Colonies with larger defence forces recruited larger numbers of ants, resulting in faster herbivore discovery (r 2 =0.80; n=17; P<0.001) and reduced herbivore residence time on a leaf (r 2 =0.79 n=23; P<0.001) before being driven off by the ants. We also found a negative and significant relationship between herbivore damage on leaves and ant colony size (r 2 =0.28; n=17; P<0.05). We conclude that larger colonies have more individuals available to patrol a plant and recruit defenders toward herbivores. This reduces the time spent to locate and expel susceptible herbivores from the plant. Since the plant probably benefits from reduced herbivory and the plant provides food for the ants, the association between Azteca muelleri and Cecropia pachystachya appears mutualistic.