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The individual identification of animals is essential for long-term population ecology studies. Injuries and tag loss can negatively impact animal welfare and parameter estimates. We used time-to-failure curves and multistate mark-recapture models to estimate injury rates, body condition decline, tag loss and survival probabilities associated with two tags commonly used in bats: metallic arm bands and steel ball chain collars. We monitored two colonies of Carollia perspicillata at União Biological Reserve, southeastern Brazil, from 2013 to 2019. Every other month, we marked individuals with arm bands, collars or both. Collars did not cause noticeable injuries, but were lost at a higher rate than arm bands (1.5–2.5 times). The arm band-related injury probability between captures was ~ 0.2, and after 17 months half the marked animals developed injuries. Animals marked as juveniles were less likely to get injured than adults. Injuries were associated with a lower body condition in females. Body condition was positively associated with apparent survival; however, a direct effect of arm band injuries on survival estimates was not observed. The tag loss rates caused a negative bias in survival estimates. Mark-recapture studies should evaluate the efficacy of the marking technique, accounting for potential animal injury, tag loss, and bias in parameter estimation. Marking individuals should be limited to studies that monitor species with high recapture probability, using the least harmful tags possible, and balancing the burden to the animals with the potential to generate knowledge.

Studies on functional performance are important to understand the processes responsible for the evolution of diversity. Morphological trait variation within species influences the energetic cost of locomotion and impacts life history traits, with ecological and evolutionary consequences. This study examined wing morphology correlates of flight performance measured by energetic expenditure in the Seba's short-tailed bat, Carollia perspicillata. In the flight experiments, nature caught bats (59 females, 57 males) were allowed to fly for three minutes in a room. After each flight, thermographic images were taken to measure body temperature, and biophysical models were used to calculate sensible heat loss as a measure of energetic expenditure. Wing morphological traits were measured for each individual and associated with heat loss and power required to fly on performance surfaces. Wing morphological traits explained 7-10% of flight energetic cost, and morphologies with the best performance would save the energy equivalent to 9-30% of total daily requirements. The optimal performance areas within the C. perspicillata morphospace were consistent with predicted selection trends from the literature. A trade-off between demands for flight speed and maneuverability was observed. Wing loading and camber presented sexual dimorphism. These morphological differences are likely associated with more economical but less maneuverable flight in females, leading them to fly more often in open areas along the forest edge. Our findings demonstrate how small scale changes in wing morphology can affect life history strategies and fitness. This article is protected by copyright. All rights reserved.

Despite the remarkable morphological modifications that occurred in the thoracic limbs of bats, information about the brachial plexus in this group is still scarce. The present study aimed to describe the origin, structure, and distribution of these peripheral nerves in four Phyllostomidae species. Both antimeres of six Artibeus lituratus, five Desmodus rotundus, seven Glossophaga soricina, and five Phyllostomus hastatus-all adult males from the Adriano Lúcio Peracchi Collection (UFRRJ)-were dissected. After complete exposure of the structure, we found that the brachial plexus of D. rotundus and P. hastatus is formed by the same roots (C5-T1), whereas the fourth cervical spinal nerve and the second thoracic spinal nerve are present in G. soricina (C4-T1) and A. lituratus (C5-T2), respectively. There was intraspecific variation and asymmetry in the origin of the structure and the combinations of nerve segments forming terminal branches. The distribution to the target muscles and patagium, however, was not subject to significant variation in our sample. Data presented here support the presence of two prevailing conditions in distribution of nerves to the bat muscles, and the innervation of the membranes seems to be explained by embryogenesis. Although the brachial plexus in phyllostomid bats is similar to that of other terrestrial Laurasiatheria, aspects identified in these bats, apparently unique to Chiroptera, may be related to anatomical changes in the thoracic limbs functionally linked to flight.

Systems of embryonary classification are essential tools in developmental and comparative biology. They are established in a process called staging, in which the chronology of appearance and development of morphological characters is recorded in a series of embryos, with these ontogenetic events being used to recognize stages. We examined 29 embryos of Artibeus. Then, we analyzed embryonic growth through the following parameters: Crown-rump length, uterine diameter, forearm length, and nose leaf length. We analyze morphological characters along the prenatal development of three species of Artibeus and provide a stage system based on Cretekos et al. (2005). These results are then compared to those available for other bat species staged so far, and we highlight some modifications in the characters and nomenclature adopted here in an attempt to make our staging system more generalizable in respect to the order Chiroptera. The analysis of embryonic staging in different species allowed the identification of stages that share common characteristics among species (e.g., formation of the neural tube and appearance of the pharyngeal arches and limb buds) and stages with characters that may be used to separate groups (e.g., presence or absence of noseleaf and tail). Most of the development in Artibeus corroborated the staging proposed by Cretekos et al. (2005) for Carollia perspicillata. The analysis of parameters studied here and other characteristics can set the foundation for standardization in several bat groups. We also propose adaptations to the staging system based on characteristics common to all groups.

Bite force measurements are relevant to the functional performance and provide insights about ecology and evolution of vertebrates. Bats are a good model system for ecomorphological studies of bite force because communities are species rich and the animals are easy to capture and handle. Investigators are careful with standardization within studies to ensure internal validity, but differences in methods for measuring bite forces in live animals could decrease external validity (generalization) of results. We assembled published and new estimates of in vivo bite forces, where the same species were measured by different investigators using different methods in different locations, to perform a meta-analysis, assess the statistical heterogeneity of results and examine possible causes of among-study differences. We also compared the combined measurements of in vivo bite force to estimated bite forces from skull pictures of museum specimens (dry skull model) to check for biases and validate the estimates. The results showed that in vivo bite force measurements were statistically heterogeneous, particularly for species with four or more published estimates. Body mass measurements were also heterogeneous but size could not explain the experimental differences in bite force within species. Type of sensor used also did not explain the among-study variation. The random differences among studies did not, however, compromise external validity, because at an evolutionary scale, variation within species (including that due to heterogeneity) is less than 10% of variation among species. Therefore, the biological interpretation of results is not affected by experimental heterogeneity. Estimates of bite force using museum specimens were validated as unbiased predictors of in vivo bite forces via regression, and the macroevolutionary pattern of variation among dietary specializations was consistent among estimates, suggesting reasonable external validity for both model and in vivo measurements of bite force at an evolutionary scale.

The measurement of fitness in wild populations is a challenging task, and a number of proxies have been proposed with different degrees of success. Developmental instability/stability (DI) is an organismal property associated with variance in bilateral asymmetry (fluctuating asymmetry-FA) and a correlated effect on fitness. This study provides evidence to corroborate the hypothesis that asymmetry partly reflects DI and is correlated with a reduction in fitness measured by survival and reproduction in bats. We studied two colonies of the bat Carollia perspicillata in southeastern Brazil over 5 years, marking and recapturing individuals. Gaussian mixture models for signed Forearm Asymmetry (ForA) distribution indicated that ~20% of asymmetry variation was due to DI heterogeneity among individuals. ForA, body condition (Scaled Mass Index-SMI) and Forearm Length (ForL) were used as predictors of survival probability in Cormack-Jolly-Seber models. Asymmetry was negatively associated with survival, whereas SMI and ForL were positively associated. The male C. perspicillata defend sites within the roost that are favoured by female harems, but there are mating opportunities for bachelor males, leading to both territorial disputes and sperm competition. As predicted by sexual selection, ForA was negatively associated with relative Testicle Length, a measure of reproductive potential. In females, ForA was negatively associated with the probability of two pregnancies (as opposed to one) in a given breeding season. The effect magnitudes and directions of associations suggest that asymmetry, even though not perfectly reflecting DI variation, is a useful predictor for fitness components in C. perspicillata.

Lists of Brazilian bats have been compiled since the late 19th century, with remarkable variation in the criteria for species inclusion and use of nomenclature. To update the list of extant bat species that occur in Brazil, the Brazilian Bat Research Society created the Committee of the List of Brazilian Bats. Here we report the first result of the work of this Committee: a list with nine families, 68 genera, and 178 species with documented occurrence in Brazil, including nomenclatural comments. We also present two additional species lists: one with doubtful records (10 species) and other with erroneous records (six species). Since the beginning of the 21st century, 35 new bat species have been recorded for Brazil, and we anticipate that more species will be uncovered over the next years. © 2014 Check List and Authors.

From 1814 to 1831, the Prussian naturalist Friedrich Sellow collected 263 mammals in Brazil and Uruguay. Upon receiving the specimens, the curator of the Berlin Zoological Museum, Martin Lichtenstein, removed the original labels and replaced with ones containing more generalized locations. As a consequence, several type specimens have now dubious type localities. We examined these types as well as geographically restricted mammals collected by Sellow. In some cases, there are inconsistencies between the specimen label and the collection catalog regarding the collecting locality. We conclude that the locality information on the lectotype of the tent-making bat Uroderma bilobatum is mistakenly identified, and therefore, we restrict it to “eastern Brazil”. We designate a lectoype for Azara’s agouti, Dasyprocta azarae, and restrict its type locality to the region travelled by Sellow in São Paulo. Although there are no recent records of the woolly giant rat, Kunsia tomentosus, from its type locality, the species may have been recently extirpated from the area. Two primate specimens supposedly collected by Sellow, a silvery marmoset, Mico argentatus, and a black tamarin, Saguinus niger, occur only in the Amazonia of northern Brazil, outside the route travelled by the naturalist, and are more likely to have been collected by Sieber. Our investigations stress the importance of collecting vouchers for verifying species occurrence records and establishing a solid taxonomy.

Conjoined twinning is an embryological anomaly rarely reported in wild mammals and with only two previous records in Chiroptera. Here, we report a case of dicephalic parapagus conjoined twins in the Neotropical phyllostomid genus Artibeus. These twins are males and present separated heads and necks, but a conjoined trunk with an expanded upper thoracic region. They developed two complete forelimbs and two complete hindlimbs, all laterally to the trunk. There is a volume in the upper midback and between the heads that resembles a third rudimentary medial forelimb, but X-ray images only suggest the presence of medial skeletal elements of the pectoral girdle (clavicle and scapulae) in this region. The X-ray images also show that vertebral columns run separated from head until the base of lumbar region, where they form a single structure. Using ultrasound images, we detected the presence of two similarly sized and apparently separated hearts. The accumulation of study cases like this will help in the understanding of patterns and process behind this phenomena, and collection material plays a key role in this context.

No abstract available

Summary 1. Bite force is an important performance measure for vertebrate and is related to a variety of ecological challenges. Phyllostomid bats present highly diversified feeding habits associated with extensive cranial shape divergence. Biomechanical models predict that the cranial shape changes are linked to dietary variation through bite force. However, the relationship of cranial shape, diet and bite force had not been explicitly tested before. 2. Here we use a combination of geometric morphometric techniques and comparative methods to test for morphological correlates of bite force and diet in 14 phyllostomid bat species. Skull and mandible shape variation were assessed by vectors, derived from a two-block partial least squares analysis of geometric shape and size-independent bite forces. The relationship between bite force, skull shape and diet was assessed by phylogenetic generalized least square regressions. 3. Most variation in the bite force data examined here (approximately 74%) was explained by size variation alone, but the shape vectors for both skull and mandible explained a significant part of the residual variation in bite force (83% and 56%, respectively), as did the dietary differences (56%). Although the first principal component of diet variation is associated with a negative correlation between insectivory and frugivory, residual bite force and cranial shape are not associated with this diet contrast. Shape and residual bite force variation in the sample were strongly associated with the second diet component, depicting an increase in nectarivory. 4. Species with stronger bites (insectivorous and frugivorous) than expected for their sizes presented a shorter rostrum and mandible, higher skulls, and more developed muscle attachment areas. On the other hand, the characteristic cranial elongation of nectarivorous species (supporting the long tongue) is a trade-off with bite force. These morphological correlates of bite force are similar to those observed in carnivores and non-herbivorous marsupials, and can be related to morphological characters used in biomechanical models for bite force prediction. 5. Our results reinforce the effectiveness of statistically integrating geometric shape variables to bite force and diet information in the investigation of patterns of cranial shape change and trophic radiation in ecologically diverse vertebrate groups.

We report the results of small mammals inventories conducted in the region of Jaíba, northern Minas Gerais state, southeastern Brazil, from 1990 to 1995. This region is located in the southern limit of the Caatinga biome, and harbors a unique set of natural ecosystems and extensive agricultural areas. With a total effort of 2964 trap-nights and 44 net sessions, we captured 893 small mammals from 46 species, including four marsupials, 13 rodents, and 29 bats. We report on species that are endemic to the Caatinga (Wiedomys pyrrhorhinos and Xeronycteris vieirai), and species that are new to the mammal fauna of the state of Minas Gerais (Tonatia saurophila, X. vieirai, and Myotis lavali). We also provide the first valid voucher-supported record of Micronycteris sanborni from southeastern Brazil, and extend the known range of X. vieirai 800 km southward. All bats highlighted here as endemic or representing new records were associated to limestone outcrops, suggesting that preservation of this kind of habitat may be particularly relevant to the conservation of these mammals. Reportamos os resultados de inventários de pequenos mamíferos conduzidos na região de Jaíba, norte de Minas Gerais, sudeste do Brasil, entre 1990 e 1995. Essa região está localizada no limite sul do bioma Caatinga, e abriga um conjunto único de ecossistemas naturais e extensas áreas cultivadas. Com um esforço total de 2964 armadilhas-noite e 44 sessões de captura com redes de neblina, nós capturamos 893 pequenos mamíferos, que permitiram a identificação de 46 espécies, incluindo quatro marsupiais, 13 roedores e 29 morcegos. Nós reportamos espécies endêmicas da Caatinga (Wiedomys pyrrhorhinos e Xeronycteris vieirai) e espécies que são novas para a fauna de mamíferos de Minas Gerais (Tonatia saurophila, X. vieirai e Myotis lavali). Nós também fornecemos o primeiro registro válido, com material testemunho, de Micronycteris sanborni para o sudeste do Brasil, e estendemos a distribuição geográfica conhecida de X. vieirai em 800 km na direção sul. Todos os morcegos destacados aqui como endêmicos ou representando novos registros estiveram associados a afloramentos de calcário, sugerindo que a preservação deste tipo de hábitat pode ser particularmente relevante para conservação desses mamíferos.

Ao longo do tempo, os ambientes naturais foram progressivamente transformados em pequenos remanescentes, sendo a perda de habitat uma das principais ameaças à biodiversidade. O presente estudo foi realizado em dois fragmentos florestais da Fazenda Congonhas, município de Rancho Alegre – PR, sendo um deles uma reserva legal de mata nativa (107,8 ha) e o outro uma área de reflorestamento (11,8 ha), com os objetivos de conhecer a riqueza e a abundância de morcegos; verificar quais espécies encontradas na mata também utilizam a área de reflorestamento e também observar as diferenças tanto do número de indivíduos como das espécies capturadas nas diferentes estações do ano. Considerou-se a riqueza absoluta de espécies (S), a abundância e a diversidade, obtida através do Índice de Shannon-Wiener (H’). Quatro coletas por mês foram realizadas durante o período de abril/2007 a março/2008, sendo duas noites consecutivas em cada fragmento. Oito redes de neblina foram armadas em trilhas no interior da mata e do reflorestamento, vistoriadas a cada 15 minutos, por 6 horas após o escurecer. Na mata nativa foram amostrados 397 indivíduos, 14 espécies e 10 gêneros contra 105 indivíduos, 6 espécies e 4 gêneros no reflorestamento. Artibeus lituratus (Olfers, 1818) foi a espécie mais capturada em ambos os fragmentos (n=328; 65,3%), seguida por Artibeus fimbriatus Gray, 1838 (n=44; 8,8%) e Artibeus jamaicensis Leach, 1821 (n=30; 6,0%). As demais espécies, Platyrrhinus lineatus (E. Geoffroy, 1810), Carollia perspicillata (Linnaeus, 1758), Sturnira lilium (E. Geoffroy, 1810), Chrotopterus auritus (Peters, 1856), Desmodus rotundus (E. Geoffroy, 1810), Michronycteris megalotis (Gray, 1842), Phyllostomus hastatus (Pallas, 1767), Phyllostomus discolor Wagner, 1843, Myotis levis (I. Geoffroy1824), Myotis nigricans (Schinz, 1821) e Lasiurus blossevillii (Lesson & Garnot, 1826) totalizaram 19,9% das capturas. A mata nativa apresentou maior riqueza (S=14) e diversidade (H’=1,4802) quando comparada ao reflorestamento (S=6; H’= 0,57015). O teste t (t=7,1075) mostrou diferença significativa entre os valores de diversidade. A preservação do fragmento de mata nativa é importante, pois apresenta as melhores condições para manter populações mais diversas de espécies. A implantação do reflorestamento é de grande importância, pois pode impedir mudanças radicais no microclima do contorno do fragmento de floresta. Throughout the time, the natural environments gradually had been transformed in small remainders, being the loss of habitat one of the main threats to biodiversity. The present study it was carried through in two forest fragment of the Fazenda Congonhas, city of Rancho Alegre- PR, being an one of them legal reserve of native forest (107.8 ha) and the other a reforestation area (11.8 ha), with the objectives to know the richness and the abundance of bats; to verify which species found in the native forest also they use the reforestation area and also to observe the differences in such a way of the number of individuals as of the species captured in the different stations of the year. It was considered absolute richness of species (S), the abundance and the diversity, gotten through the Shannon-Wiener Index (H'). Four collections for month had been carried during the period of abril/2007 to março/2008, being two consecutive nights in each fragment. Eight “mist nets” had been set in tracks in the interior of the forest and the reforestation area, being inspected to each 15 minutes, for 6 hours after sunset. In the native forest 397 individuals had been captured, 14 species and 10 genus against 105 individuals, 6 species and 4 genus in the reforestation area. Artibeus lituratus (Olfers, 1818) was the species more captured in both the fragments (n=328; 65.3%), followed by Artibeus fimbriatus Gray, 1838 (n=44; 8.8%) and Artibeus jamaicensis Leach, 1821 (n=30; 6.0%). The others species, Platyrrhinus lineatus (E. Geoffroy, 1810), Carollia perspicillata (Linnaeus, 1758), Sturnira lilium (E. Geoffroy, 1810), Chrotopterus auritus (Peters, 1856), Desmodus rotundus (E. Geoffroy, 1810), Michronycteris megalotis (Gray, 1842), Phyllostomus hastatus (Pallas, 1767), Phyllostomus discolor Wagner, 1843, Myotis levis (I. Geoffroy1824), Myotis nigricans (Schinz, 1821) and Lasiurus blossevillii (Lesson & Garnot, 1826) had totalized 19.9% of the captures. The native forest presented greater richness (S=14) and diversity (H '=1.4802) when compared to reforestation area (S=6; H'=0.57015). Test t (t=7.1075) showed significant difference between the values of diversity. The preservation of native fragment is important; therefore it presents the best conditions to keep more diverse populations of species. The implantation of the reforestation is very important, because it can hinder radical changes in the microclimate around of the forest fragment.