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Inventories are the basis of every work with biodiversity, with increased importance due to the current environmental crisis. Bats are one of the most diverse groups of mammals, with high ecologic versatility and are good bioindicators to monitor environmental impacts. We performed a two-stage survey at an Atlantic Forest reserve in the State of Paraiba, the first stage registering 187 individuals of 24 species and the second stage, 1073 individuals of 11 species; the second stage’s richness being a subset of the first as pointed by the Mann-Whitney test. The second stage was more efficient in accumulating individuals, while the first accumulated species more efficiently. The diversity estimation (Chao 1) pointed that the survey was efficient in registering 93.75% of the species richness predicted for the area, and that diversity estimators are more reliable to evaluate sampling efficiency than methods based in number of captures. The inventory survey registered over 42% of the species richness registered for the State of Paraiba, as well as included a new register, Natalus stramineus , pointing that the bat richness for the state is yet to be sufficiently studied.

Our objective was to estimate and analyze the body‐size distribution parameters of terrestrial mammal assemblages at different spatial scales, and to determine whether these parameters are controlled by local ecological processes or by larger‐scale ones. Based on 93 local assemblages, plus the complete mammal assemblage from three continents (Africa, North, and South America), we estimated three key distribution parameters (diversity/size slope, skewness, and modal size) and compared the values to those expected if size distributions are mainly controlled by local interactions. Mammal diversity decreased much faster as body size increased than predicted by fractal niche theory, both at continental and at local scales, with continental distributions showing steeper slopes than the localities within them. South America showed a steeper slope (after controlling for species diversity), compared to Africa and North America, at local and continental scales. We also found that skewness and modal body size can show strikingly different correlations with predictor variables, such as species richness and median size, depending on the use of untransformed versus log‐transformed data, due to changes in the distribution density generated by log‐transformation. The main differences in slope, skewness, and modal size between local and continental scales appear to arise from the same biogeographical process, where small‐sized species increase in diversity much faster (due to higher spatial turnover rates) than large‐sized species. This process, which can operate even in the absence of competitive saturation at local scales, generates continental assemblages with steeper slopes, smaller modal sizes, and higher right skewness (toward small‐sized species) compared to local communities. In addition, historical factors can also affect the size distribution slopes, which are significantly steeper, in South American mammal assemblages (probably due to stronger megafauna extinction events in South America) than those in North America and Africa.

Estimate the richness of a community with accuracy despite differences in sampling effort is a key aspect to monitoring high diverse ecosystems. We compiled a worldwide multitaxa database, comprising 185 communities, in order to study the relationship between the percentage of species represented by one individual (singletons) and the intensity of sampling (number of individuals divided by the number of species sampled). The database was used to empirically adjust a correction factor to improve the performance of non-parametrical estimators under conditions of low sampling effort. The correction factor was tested on seven estimators (Chao1, Chao2, Jack1, Jack2, ACE, ICE and Bootstrap). The correction factor was able to reduce the bias of all estimators tested under conditions of undersampling, while converging to the original uncorrected values at higher intensities. Our findings led us to recommend the threshold of 20 individuals/species, or less than 21% of singletons, as a minimum sampling effort to produce reliable richness estimates of high diverse ecosystems using corrected non-parametric estimators. This threshold rise for 50 individuals/species if non-corrected estimators are used which implies in an economy of 60% of sampling effort if the correction factor is used.

We reviewed topographical homologies in the upper tooth morphology of bats and analyzed the implications to relationships among higher taxa within Chiroptera. A standardized terminology for the upper molars of bats is proposed, taking into consideration the nomenclature adopted for tribosphenic mammals. Major patterns of variation in crown morphology of chiropteran upper molars were reevaluated, and 2 new structures were identified: mesoconule and mesoconule crista. The main controversies in the literature regarding terminology and structural identity in the upper molars of chiropterans are discussed. Forty-eight dental morphological characters are presented for extant bats and the extinct Icaronycteridae, with the exception of Pteropodidae, which has lost the tribosphenic dental pattern. These were combined with 191 characters of other morphological systems from the literature. The tree obtained from parsimony analyses mostly agrees with previous proposals based on morphology. However, major differences were found: the position of Noctilionoidea at the base of the radiation of modern microchiropterans, which formed a trichotomy with Yinochiroptera (including Emballonuridae) and the remaining Yangochiroptera; Antrozoinae disassociated from the other Vespertilionidae, forming a poorly supported clade with Mystacinidae and Molossidae; and the relationship between the sister taxa Myotinae and Miniopterinae within Vespertilionidae.