Taxonomic re-evaluation of New World Eptesicus and Histiotus (Chiroptera: Vespertilionidae), with the description of a new genus

Eptesicus Rafinesque, 1820 is widely distributed in the Old and New World (26 species), and Histiotus Gervais, 1856 is a South American endemic (11 species). Molecular phylogenies have recovered Eptesicus (sensu lato) as polyphyletic, with New World Eptesicus and the sister genus Histiotus in a paraphyletic American clade sister to Old World Eptesicus. Based on these phylogenetic reconstructions, authors have treated Histiotus as either a subgenus of Eptesicus or restricted Eptesicus to the New World species, treating Histiotus as a full genus, and using the name Cnephaeus Kaup, 1829 at the generic rank to comprise Old World Eptesicus. Based on recently published molecular studies, and on novel qualitative and quantitative morphological comparisons of representatives of Histiotus and New and Old World Eptesicus, we provide evidence for restricting the name Eptesicus to the species E. fuscus (Palisot de Beauvois, 1796) and E. guadeloupensis Genoways & Baker, 1975, allocating the remaining New World species under a new genus, keeping Histiotus as a full genus, and raising Cnephaeus to generic rank to comprise all Old World taxa currently under Eptesicus. This arrangement resolves the paraphyly of New World Eptesicus, and promotes taxonomic stability for Histiotus, which is a well-established genus of easily recognizable Neotropical bats and treated separate from Eptesicus by most authorities.

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.

Redescription of Myotis atacamensis (Chiroptera: Vespertilionidae) with neotype designation

Myotis atacamensis (Lataste, 1892) was described based on three syntypes from San Pedro de Atacama, Chile. The type series is lost. The original description was based on few external and cranial characters, and the diagnosis became obsolete and useless considering the current diversity of South American Myotis. Based on 12 specimens of M. atacamensis from southern Peru and northern Chile, we provide a morphological comparison with its South American congeners, designate a neotype, and provide a new diagnosis.(AU)

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 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.

Range extension of Myotis midastactus​ (Chiroptera, Vespertilionidae) to Paraguay.

BACKGROUND: Myotis midastactus Moratelli and Wilson, 2014 (Vespertilionidae, Myotinae) was described from the Myotis simus Thomas, 1901 complex based on collections from the Bolivian Savannah. NEW INFORMATION: Four vouchers previously assigned to M. simus from the Alto Chaco in Paraguay (West of the Paraguay River) are reassigned here to M. midastactus. These specimens extend the geographic distribution of M. midastactus 1200 km southward, and constitute the first evidence of the species in the country. Based on other material from the Brazilian Pantanal and Cerrado, Central Paraguay and north-eastern Argentina, we also discuss the identity of simus-like populations south of the Amazon Basin. The status of these populations is still unclear, but the little evidence we have at hand indicates that these populations may represent another taxon-M. guaycuru Proença, 1943; whereas M. simus seems to be restricted to the Amazon basin. This hypothesis is still very speculative and requires further investigation. With the assignment of material from Alto Chaco to M. midastactus, seven species of Myotis are confirmed for Paraguay: M. albescens, M. lavali, M. levis, M. midastactus, M. nigricans, M. riparius, and M. ruber.

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.

The identity of Myotis punensis (Chiroptera: Vespertilionidae)

Currently twelve species of Myotis Kaup, 1829 (Vespertilionidae: Myotinae) are recognized from South America, with several other named taxa regarded as synonyms, among them Myotis punensis J.A. Allen, 1914. This name was first regarded as a junior synonym of Myotis albescens (É. Geoffroy, 1806) and subsequently of Myotis nigricans (Schinz, 1821). To address the taxonomic status of the holotype of M. punensis, we compared it to all South American species in the genus. The fringe of hairs on the trailing edge of the uropatagium, the fur color, and external and skull dimensions all suggest M. punensis should be treated as a junior synonym of M. albescens

The identity of Myotis punensis (Chiroptera: Vespertilionidae)

Currently twelve species of Myotis Kaup, 1829 (Vespertilionidae: Myotinae) are recognized from South America, with several other named taxa regarded as synonyms, among them Myotis punensis J.A. Allen, 1914. This name was first regarded as a junior synonym of Myotis albescens (É. Geoffroy, 1806) and subsequently of Myotis nigricans (Schinz, 1821). To address the taxonomic status of the holotype of M. punensis, we compared it to all South American species in the genus. The fringe of hairs on the trailing edge of the uropatagium, the fur color, and external and skull dimensions all suggest M. punensis should be treated as a junior synonym of M. albescens

The identity of Myotis punensis (Chiroptera: Vespertilionidae)

Currently twelve species of Myotis Kaup, 1829 (Vespertilionidae: Myotinae) are recognized from South America, with several other named taxa regarded as synonyms, among them Myotis punensis J.A. Allen, 1914. This name was first regarded as a junior synonym of Myotis albescens (É. Geoffroy, 1806) and subsequently of Myotis nigricans (Schinz, 1821). To address the taxonomic status of the holotype of M. punensis, we compared it to all South American species in the genus. The fringe of hairs on the trailing edge of the uropatagium, the fur color, and external and skull dimensions all suggest M. punensis should be treated as a junior synonym of M. albescens

Lista atualizada de quirópteros da Amazônia Brasileira

Summary We present an updated checklist on bats of the Amazon Basin in Brazil, based on our collection of 3.081 specimens in 12 areas in the Basin and a review of the existing literature. The list consists of 95 species belonging to 51 genera and 9 families: 3 species (Micronycteris hirsuta, Natalus stramineus and Rhogessa tumida) are being cited for the first time as present in the Amazon Basin; of the remaining 92 species reported by previous workers. 68 were registered and confirmed by the present authors.

Resumo É apresentada uma lista atualizada de quirópteros da região amazônica brasileira, baseada em nossa coleção de 3.081 exemplares capturados em 12 áreas na Bacia Amazônica e com referência às literaturas anteriormente publicadas. A lista conta com 95 espécies de 51 gêneros e 9 famílias, sendo 3 espécies (Micronycteris hirsuta, Natalus stramineus e Rhogessa tumida) citadas pela primeira vez como ocorrendo na região; e das demais alistadas por pesquisadores anteriores, são registradas e confirmadas 68 espécies.