Old specimens for old branches: Assessing effects of sample age in resolving a rapid Neotropical radiation of squirrels.

Ultraconserved Elements (UCEs) have been useful to resolve challenging phylogenies of non-model clades, unpuzzling long-conflicted relationships in key branches of the Tree of Life at both deep and shallow levels. UCEs are often reliably recovered from historical samples, unlocking a vast number of preserved natural history specimens for analysis. However, the extent to which sample age and preservation method impact UCE recovery as well as downstream inferences remains unclear. Furthermore, there is an ongoing debate on how to curate, filter, and properly analyze UCE data when locus recovery is uneven across sample age and quality. In the present study we address these questions with an empirical dataset composed of over 3800 UCE loci from 219 historical and modern samples of Sciuridae, a globally distributed and ecologically important family of rodents. We provide a genome-scale phylogeny of two squirrel subfamilies (Sciurillinae and Sciurinae: Sciurini) and investigate their placement within Sciuridae. For historical specimens, recovery of UCE loci and mean length per locus were inversely related to sample age; deeper sequencing improved the number of UCE loci recovered but not locus length. Most of our phylogenetic inferences-performed on six datasets with alternative data-filtering strategies, and using three distinct optimality criteria-resulted in distinct topologies. Datasets containing more loci (40% and 50% taxa representativeness matrices) yielded more concordant topologies and higher support values than strictly filtered datasets (60% matrices) particularly with IQ-Tree and SVDquartets, while filtering based on information content provided better topological resolution for inferences with the coalescent gene-tree based approach in ASTRAL-III. We resolved deep relationships in Sciuridae (including among the five currently recognized subfamilies) and relationships among the deepest branches of Sciurini, but conflicting relationships remain at both genus- and species-levels for the rapid Neotropical tree squirrel radiation. Our results suggest that phylogenomic consensus can be difficult and heavily influenced by the age of available samples and the filtering steps used to optimize dataset properties.

Expert range maps of global mammal distributions harmonised to three taxonomic authorities.

Aim: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). Location: Global. Taxon: All extant mammal species. Methods: Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). Results: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use. Main conclusion: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

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.

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.

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.

Museomics of tree squirrels: a dense taxon sampling of mitogenomes reveals hidden diversity, phenotypic convergence, and the need of a taxonomic overhaul.

BACKGROUND: Tree squirrels (Sciuridae, Sciurini), in particular the highly diverse Neotropical lineages, are amongst the most rapidly diversifying branches of the mammal tree of life but also some of the least known. Negligence of this group by systematists is likely a product of the difficulties in assessing morphological informative traits and of the scarcity or unavailability of fresh tissue samples for DNA sequencing. The highly discrepant taxonomic arrangements are a consequence of the lack of phylogenies and the exclusive phenotypic-based classifications, which can be misleading in a group with conservative morphology. Here we used high-throughput sequencing and an unprecedented sampling of museum specimens to provide the first comprehensive phylogeny of tree squirrels, with a special emphasis on Neotropical taxa. RESULTS: We obtained complete or partial mitochondrial genomes from 232 historical and modern samples, representing 40 of the 43 currently recognized species of Sciurini. Our phylogenetic analyses-performed with datasets differing on levels of missing data and taxa under distinct analytical methods-strongly support the monophyly of Sciurini and consistently recovered 12 major clades within the tribe. We found evidence that the diversity of Neotropical tree squirrels is underestimated, with at least six lineages that represent taxa to be named or revalidated. Ancestral state reconstructions of number of upper premolars and number of mammae indicated that alternative conditions of both characters must have evolved multiple times throughout the evolutionary history of tree squirrels. CONCLUSIONS: Complete mitogenomes were obtained from museum specimens as old as 120 years, reinforcing the potential of historical samples for phylogenetic inferences of elusive lineages of the tree of life. None of the taxonomic arrangements ever proposed for tree squirrels fully corresponded to our phylogenetic reconstruction, with only a few of the currently recognized genera recovered as monophyletic. By investigating the evolution of two morphological traits widely employed in the taxonomy of the group, we revealed that their homoplastic nature can help explain the incongruence between phylogenetic results and the classification schemes presented so far. Based on our phylogenetic results we suggest a tentative supraspecific taxonomic arrangement for Sciurini, employing 13 generic names used in previous taxonomic classifications.

The Dogma of Dingoes-Taxonomic status of the dingo: A reply to Smith et al.

Adopting the name Canis dingo for the Dingo to explicitly denote a species-level taxon separate from other canids was suggested by Crowther et al.  (2014) as a means to eliminate taxonomic instability and contention. However, Jackson et al.  (2017), using standard taxonomic and nomenclatural approaches and principles, called instead for continued use of the nomen C. familiaris for all domestic dogs and their derivatives, including the Dingo. (This name, C. familiaris, is applied to all dogs that derive from the domesticated version of the Gray Wolf, Canis lupus, based on nomenclatural convention.) The primary reasons for this call by Jackson et al.  (2017) were: (1) a lack of evidence to show that recognizing multiple species amongst the dog, including the Dingo and New Guinea Singing Dog, was necessary taxonomically, and (2) the principle of nomenclatural priority (the name familiaris Linnaeus, 1758, antedates dingo Meyer, 1793). Overwhelming current evidence from archaeology and genomics indicates that the Dingo is of recent origin in Australia and shares immediate ancestry with other domestic dogs as evidenced by patterns of genetic and morphological variation. Accordingly, for Smith et al.  (2019) to recognise Canis dingo as a distinct species, the onus was on them to overturn current interpretations of available archaeological, genomic, and morphological datasets and instead show that Dingoes have a deeply divergent evolutionary history that distinguishes them from other named forms of Canis (including C. lupus and its domesticated version, C. familiaris). A recent paper by Koepfli et al.  (2015) demonstrates exactly how this can be done in a compelling way within the genus Canis-by demonstrating deep evolutionary divergence between taxa, on the order of hundreds of thousands of years, using data from multiple genetic systems. Smith et al.  (2019) have not done this; instead they have misrepresented the content and conclusions of Jackson et al.  (2017), and contributed extraneous arguments that are not relevant to taxonomic decisions. Here we dissect Smith et al.  (2019), identifying misrepresentations, to show that ecological, behavioural and morphological evidence is insufficient to recognise Dingoes as a separate species from other domestic dogs. We reiterate: the correct binomial name for the taxon derived from Gray Wolves (C. lupus) by passive and active domestication, including Dingoes and other domestic dogs, is Canis familiaris. We are strongly sympathetic to arguments about the historical, ecological, cultural, or other significance of the Dingo, but these are issues that will have to be considered outside of the more narrow scope of taxonomy and nomenclature.

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.

Taxonomic revision of the olingos (Bassaricyon), with description of a new species, the Olinguito.

We present the first comprehensive taxonomic revision and review the biology of the olingos, the endemic Neotropical procyonid genus Bassaricyon, based on most specimens available in museums, and with data derived from anatomy, morphometrics, mitochondrial and nuclear DNA, field observations, and geographic range modeling. Species of Bassaricyon are primarily forest-living, arboreal, nocturnal, frugivorous, and solitary, and have one young at a time. We demonstrate that four olingo species can be recognized, including a Central American species (Bassaricyon gabbii), lowland species with eastern, cis-Andean (Bassaricyon alleni) and western, trans-Andean (Bassaricyon medius) distributions, and a species endemic to cloud forests in the Andes. The oldest evolutionary divergence in the genus is between this last species, endemic to the Andes of Colombia and Ecuador, and all other species, which occur in lower elevation habitats. Surprisingly, this Andean endemic species, which we call the Olinguito, has never been previously described; it represents a new species in the order Carnivora and is the smallest living member of the family Procyonidae. We report on the biology of this new species based on information from museum specimens, niche modeling, and fieldwork in western Ecuador, and describe four Olinguito subspecies based on morphological distinctions across different regions of the Northern Andes.

Genetic diversity of neotropical Myotis (chiroptera: vespertilionidae) with an emphasis on South American species.

BACKGROUND: Cryptic morphological variation in the Chiropteran genus Myotis limits the understanding of species boundaries and species richness within the genus. Several authors have suggested that it is likely there are unrecognized species-level lineages of Myotis in the Neotropics. This study provides an assessment of the diversity in New World Myotis by analyzing cytochrome-b gene variation from an expansive sample ranging throughout North, Central, and South America. We provide baseline genetic data for researchers investigating phylogeographic and phylogenetic patterns of Myotis in these regions, with an emphasis on South America. METHODOLOGY AND PRINCIPAL FINDINGS: Cytochrome-b sequences were generated and phylogenetically analyzed from 215 specimens, providing DNA sequence data for the most species of New World Myotis to date. Based on genetic data in our sample, and on comparisons with available DNA sequence data from GenBank, we estimate the number of species-level genetic lineages in South America alone to be at least 18, rather than the 15 species currently recognized. CONCLUSIONS: Our findings provide evidence that the perception of lower species richness in South American Myotis is largely due to a combination of cryptic morphological variation and insufficient sampling coverage in genetic-based systematic studies. A more accurate assessment of the level of diversity and species richness in New World Myotis is not only helpful for delimiting species boundaries, but also for understanding evolutionary processes within this globally distributed bat genus.