Rabies virus circulation in a highly diverse bat assemblage from a high-risk area for zoonoses outbreaks in the Brazilian Amazon.

Bats are the second most diverse order of mammals and play a central role in ecosystem dynamics. They are also important reservoirs of potentially zoonotic microorganisms, of which rabies virus is the most lethal among the bat-transmitted zoonotic pathogens. Importantly, recent outbreaks of human rabies have been reported from the Brazilian Amazon. Here we present a survey of bat species and rabies virus (RABV) circulation in a bat assemblage in the Marajó region, northern Brazil. Using data from mist-net captures and bioacoustic sampling, 56 bat species were recorded along the Jacundá River basin over a 10-day expedition in November 2022. For the investigation of RABV, we used the direct fluorescent antibody test (DFAT) and the rapid fluorescent focus inhibition test (RFFIT). In total, 159 bat individuals from 22 species were investigated for RABV. Five adults of the common vampire bat, Desmodus rotundus, showed RABV-specific antibodies in serum samples. Additionally, we report on local residents with injuries caused by D. rotundus bites and the occurrence of colonies of non-hematophagous bats from different species roosting inside human residences. This scenario raises concerns about the risks of new cases of human rabies and other zoonotic diseases associated with bats in the region and highlights the need for epidemiological surveillance and mitigation measures to prevent outbreaks of emerging infectious diseases.

Forecasting climate change impacts on neotropical Myotis: Insights from ecological niche models for conservation strategies.

Myotis originated during the Oligocene in Eurasia and has become one of the most diverse bat genera, with over 140 species. In the case of neotropical Myotis, there is a high degree of phenotypic conservatism. This means that the taxonomic and geographic limits of several species are not well understood, which constrains detailed studies on their ecology and evolution and how to effectively protect these species. Similar to other organisms, bats may respond to climate change by moving to different areas, adapting to new conditions, or going extinct. Ecological niche models have become established as an efficient and widely used method for interpolating (and sometimes extrapolating) species' distributions and offer an effective tool for identifying species conservation requirements and forecasting how global environmental changes may affect species distribution. How species respond to climate change is a key point for understanding their vulnerability and designing effective conservation strategies in the future. Thus, here, we assessed the impacts of climate change on the past and future distributions of two phylogenetically related species, Myotis ruber and Myotis keaysi. The results showed that the species are influenced by changes in temperature, and for M. ruber, precipitation also becomes important. Furthermore, M. ruber appears to have been more flexible to decreases in temperature that occurred in the past, which allowed it to expand its areas of environmental suitability, unlike M. keaysi, which decreased and concentrated these areas. However, despite a drastic decrease in the spatial area of environmental suitability of these species in the future, there are areas of potential climate stability that have been maintained since the Pleistocene, indicating where conservation efforts need to be concentrated in the future.

Systematic review of Myotis (Chiroptera, Vespertilionidae) from Chile based on molecular, morphological, and bioacoustic data.

Myotis is the most diverse genus of bats in the world, with more than 30 species recognized in the Neotropics. However, many of these species represent cryptic complexes and are evidence of the existence of hidden diversity in several regions. Using an integrative approach based on molecular, morphological, and bioacoustic data, we performed a systematic review of Myotis species from Chile. Phylogenetic inference using cytochrome-b indicated the existence of three monophyletic lineages, and qualitative and quantitative morphological analyses supported these lineages as distinct and morphologically diagnosable taxa. Analysis of discriminant functions using parameters of echolocation calls also indicates the existence of three distinct bioacoustic clusters. Thus, all lines of evidence congruently indicate the existence of three distinct taxa. As a result, we recognize Myotis arescens as a valid and distinct species and define its taxonomic limits from the other species from Chile, Myotis atacamensis and Myotis chiloensis.

Catalogue of primary types of Neotropical Myotis (Chiroptera, Vespertilionidae).

Myotis comprises a diverse group of vespertilionid bats with worldwide distribution. Neotropical Myotis have an accentuated phenotypic conservatism, which makes species delimitation and identification difficult, hindering our understanding of the diversity, distribution, and phylogenetic relationships of taxa. To encourage new systematic reviews of the genus, a catalogue of the primary types and names is presented, current and in synonymy, for Neotropical Myotis. Currently 33 valid species (and three subspecies) are recognized, and their primary types are deposited in 12 scientific collections in the USA (30 types), Brazil (two types), England (two types), and France (one type). The names of 29 Neotropical Myotis species currently in synonymy were found. However, it is possible that some synonyms represent independent evolutionary lineages, considering recent results provided by taxonomic revisions.

ResumoMyotis compreende um grupo diverso de morcegos vespertilionídeos amplamente distribuídos ao redor do planeta. Myotis neotropicais têm um acentuado conservatismo fenotípico, o que dificulta a delimitação e identificação de espécies a partir de caracteres morfológicos, criando barreiras para a compreensão da diversidade, distribuição e relações filogenéticas entre os táxons. Visando encorajar novas revisões sistemáticas para o gênero, é apresentado este catálogo de nomes e tipos primários, válidos e sob sinonímia, para Myotis neotropicais. Atualmente, são reconhecidas 33 espécies válidas (e três subespécies) e seus tipos estão depositados em 12 coleções científicas nos EUA (30 tipos), Brasil (2 tipos), Inglaterra (2 tipos) e França (1 tipo). Compilamos 29 nomes de espécies de Myotis atualmente sob sinonímia. Entretanto, é possível que alguns desses sinônimos possam representar linhagens evolutivas independentes, considerando resultados recentes de revisões taxonômicas.

The taxonomic status of Myotis nesopolus larensis (Chiroptera, Vespertilionidae) and new insights on the diversity of Caribbean Myotis.

Myotis nesopolus currently comprises two subspecies. The nominate subspecies (M. n. nesopolus) occurs on the Caribbean islands of Curaçao and Bonaire, Netherlands Antilles, whereas M. n. larensis is known from mainland South America in northeastern Colombia and northwestern Venezuela. Our Maximum Likelihood phylogenetic analyses of cytochrome-b gene sequences recovered M. nesopolus as a paraphyletic group, with M. n. nesopolus and M. n. larensis as non-sister lineages. The haplotype network indicates that these two subspecies do not share any haplotypes and are in different evolutionary trajectories. Additionally, these two subspecies can be distinguished on the basis of qualitative and quantitative morphological traits. This pattern supports the recognition of M. nesopolus and M. larensis as full species. Our results also reveal that the assemblage of Caribbean Myotis do not form a monophyletic group. Caribbean species are phylogenetically close to mainland species from northern South America and Central America, suggesting that colonization of Caribbean islands happened multiple times.

ResumoAtualmente Myotis nesopolus compreende duas subespécies: M. n. nesopolus ocorre nas ilhas caribenhas de Curaçao e Bonaire, Antilhas Holandesas, enquanto M. n. larensis é conhecido para o continente da América do Sul, no nordeste da Colômbia e noroeste da Venezuela. Nossa inferência filogenética por Máxima Verossimilhança recuperou M. nesopolus como parafilética, com M. n. nesopolus e M. n. larensis sendo linhagens não-irmãs. Além disso, essas duas subespécies não compartilham nenhum haplótipo. Adicionalmente, as subespécies podem ser diferenciadas a partir de caracteres morfológicos e morfométricos. Esse achado suporta o reconhecimento de M. nesopolus e M. larensis como espécies distintas. Nossos resultados revelam que os Myotis do Caribe não formam um grupo monofilético. Espécies caribenhas são filogeneticamente próximas de espécies continentais das Américas Central e do Sul, sugerindo que a colonização das ilhas do Caribe aconteceu por múltiplos eventos de dispersão.

The taxonomic status of Myotis aelleni Baud, 1979 (Chiroptera, Vespertilionidae).

Myotis aelleni Baud, 1979 was described based on a large series from Chubut, Argentina, and is known only from the type locality and Río Negro, also in Argentina. According to the original description, M. aelleni is closest morphologically to M. chiloensis (Waterhouse, 1840), but can be distinguished based on the tricolored dorsal hairs and skull size and shape. The taxonomic status of M. aelleni has been questioned but the species is still treated as valid. Based on qualitative and quantitative analyses of the type series of M. aelleni, and series of M. chiloensis, including the neotype, we recognize M. aelleni as a junior synonym of M. chiloensis. M. aelleni and M. chiloensis have bicolor dorsal hairs and cannot be distinguished on the basis of the skull size and shape. After synonymy, M. chiloensis occur from Central Chile and western Argentina to central Patagonia and Tierra del Fuego archipelago. Twenty-one species of Myotis occur in South America, including Trinidad and Tobago.

Separation of monophyletic groups into distinct genera should consider phenotypic discontinuities: the case of Lasiurini (Chiroptera: Vespertilionidae).

Baird et al. (2015) split Lasiurus into three distinct genera (Aeorestes, Dasypterus and Lasiurus) based on tree topology and divergence times for the tribe Lasiurini. This arrangement has not been widely adopted by the scientific community and was criticized by Ziegler et al. (2016). More recently, Baird et al. (2017) reinforced the taxonomic arrangement of Lasiurini comprised by three genera. Baird et al. (2015, 2017) provided the most comprehensive phylogenetic analyses of Lasiurus and offer important insights on the phylogeny and alpha-taxonomy of the group. However, we disagree with the taxonomic arrangement proposed at the genus level and explain our point below.

Second record of Lasiurus ebenus (Chiroptera, Vespertilionidae), with comments on its taxonomic status.

Lasiurus ebenus was known only from the holotype, which was collected in 1991, in an Atlantic Forest remnant of Ilha do Cardoso State Park, southeastern Brazil. The species was described based on qualitative and quantitative morphological features. Since its original description, based on a single individual, the taxonomic status of Lasiurus ebenus has been questioned. Here we report a second record for the species that comes from Carlos Botelho State Park, São Paulo, ca. 100 km north from the type locality. This new record allowed us to confirm the validity of the species, by presenting additional data that fits in the distinction from sympatric congeners proposed on the original description of L. ebenus.