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Mylodontidae (Mammalia, Xenarthra) is a family of ground sloths widely distributed in the South American fossil record, with members also present in Central and North America. Within the Mylodontid...

The species within Xenarthra (sloths, anteaters, and armadillos) are quintessential South American mammals. Of the three groups, Vermilingua (anteaters) contains the fewest extant and paleontological species. Here, we sampled and sequenced the entire mitochondrial genomes (mitogenomes) of two Tamandua species (Tamandua tetradactyla and T. mexicana) (n=74) from Central and South America, as well as Myrmecophaga tridactyla (n=41) from South America. Within Tamandua, we detected three different haplogroups. The oldest (THI) contained many specimens with the T. tetradactyla morphotype (but also several with the T. mexicana morphotype) and originated in southeastern South America (currently Uruguay) before moving towards northern South America, where the THII haplogroup originated. THII primarily contained specimens with the T. mexicana morphotype (but also several with the T. tetradactyla morphotype) and was distributed in Central America, Colombia, and Ecuador. THI and THII yielded a genetic distance of 4%. THII originated in either northern South America or “in situ” in Central America with haplogroup THIII, which consisted of ~50% T. mexicana and 50% T. tetradactyla phenotypes. THIII was mostly located in the same areas as THII, i.e., Central America, Ecuador, and Colombia, though mainly in the latter. The three haplogroups overlapped in Colombia and Ecuador. Thus, T. tetradactyla and T. mexicana were not reciprocally monophyletic. For this reason, we considered that a unique species of Tamandua likely exists, i.e., T. tetradactyla. In contrast to Tamandua, M. tridactyla did not show different morphotypes throughout its geographical range in the Neotropics. However, two very divergent genetic haplogroups (MHI and MHII), with a genetic distance of ~10%, were detected. The basal haplogroup, MHI, originated in northwestern South America, whereas the more geographically derived haplogroup, MHII, overlapped with MHI, but also expanded into central and southern South America. Thus, Tamandua migrated from south to north whereas Myrmecophaga migrated from north to south. Our results also showed that temporal mitochondrial diversification for Tamandua began during the Late Pliocene and Upper Pleistocene, but for Myrmecophaga began during the Late Miocene. Furthermore, both taxa showed elevated levels of mitochondrial genetic diversity. Tamandua showed more evidence of female population expansion than Myrmecophaga. Tamandua experienced population expansion ~0.6–0.17 million years ago (Mya), whereas Myrmecophaga showed possible population expansion ~0.3–0.2 Mya. However, both taxa experienced a conspicuous female decline in the last 10 000–20 000 years. Our results also showed little spatial genetic structure for both taxa. However, several analyses revealed higher spatial structure in Tamandua than in Myrmecophaga. Therefore, Tamandua and Myrmecophaga were not subjected to the same biogeographical, geological, or climatological events in shaping their genetic structures.

Most xenarthrans have a reduced and simplified dentition that lacks enamel. However, the presence of prismatic enamel has been recorded in the Eocene armadillos Utaetus buccatus (Euphractinae) and Astegotherium dichotomus (Astegotheriini). Among extant xenarthrans, the occurrence of enamel has been recognized only in the long-nosed armadillo, Dasypus novemcinctus (Dasypodinae), but its microstructure has never been described. In this contribution, we analyse the enamel microstructure in deciduous and permanent teeth of four Dasypus species. In deciduous molariform teeth of some species, we identify an apical cap of vestigial enamel (without crystalline structure), interpreted as an amorphous ameloblastic secretion. In permanent teeth, a thin layer of true enamel is found in the apical portion of unworn molariforms. The enamel is prismatic in D. novemcinctus, but in Dasypus hybridus, Dasypus sabanicola and Dasypus punctatus it is prismless. Taking into account the Eocene species of armadillos, the ancestral condition of enamel in cingulates could have been more complex (as in other placentals) and undergone progressive reduction, as shown in the Dasypus lineage. In light of previous genetic and developmental studies, we review and briefly discuss the processes that can account for the reduction/loss of enamel in extant and extinct armadillos. The retention of enamel and the fact that this genus is the only living xenarthran with two functional generations of teeth support the early divergence of the Dasypus lineage among living cingulates. This is in agreement with morphological and molecular analyses.

The megalonychid sloth Meizonyx salvadorensis was previously known only from the holotype mandible from El Salvador. Here, we describe the first record of M. salvadorensis from the late Pleistocene...

Chaetophractus villosus and Dasypus hybridus are the most widespread and abundant armadillos inhabiting the Pampas grasslands. Studies on the parasitic fauna from an ecological perspective are scarce in both species. We describe and compare the component communities of C. villosus and D. hybridus in the Pampas ecoregion of Argentina and analyse if the composition and structure of the parasitic communities of these host species reveal trophic behaviour and/or habitat use. In the population of C. villosus 10 species of helminths were found, namely Ancylostoma caninum, Aspidodera fasciata, Aspidodera scoleciformis, Mazzia bialata, Moennigia celinae, Orihelia anticlava, Strongyloides sp., Trichohelix tuberculata (Nematoda) and Mathevotaenia sp. (Cestoda), whereas in the population of D. hybridus four species were found, A. fasciata, Delicata abbai, Pterygodermatites chaetophracti and Strongyloides sp. Only A. fasciata and Strongyloides sp. were present in both species. Prevalences and intensities were similar in Strongyloides sp. In A. fasciata, however, there were differences regarding mean intensity. Diversity was higher in C. villosus than in D. hybridus. The differences may be related to the diet, behaviour, evolutionary histories or immune response of the species studied. A combination of several of these factors would possibly influence the composition of their parasitic fauna.

Fermentative herbivorous animals have peculiar conformations of the digestive system. It is known that B. variegatus obtained the capacity for evolutionary adaptation, due to their ecology and eating habits. However, despite the literature on feeding management for this species, there is a lack of published information regarding its gastric morphology, and such information would support a better understanding on the diet and digestion of these individuals. We found seven gastric compartments, which histologically revealed three distinct patterns: an aglandular keratinized fraction (mechanical stomach) and two glandular fractions, one a mucus secretor and the other one composed of acid secreting cells (chemical stomach). With these evidences we understand that these individuals have gastric resemblance to ruminants, with some inherent peculiarities of this species, including the transit of the bolus.

Xenarthrans constitute a relict clade of endemic South American placental mammals with a long evolutionary history starting, at least, in the early Eocene. Within Xenarthra, Glyptodontidae (late Eo...

Despite the ubiquity of parasitism, the knowledge regarding fossil parasites remains fragmentary. As an example, South American clade Xenarthra was a predominant group of mammals during the Cenozoic; however, its paleoparasitological knowledge has many gaps, with only a few reports in armadillos and fewer in ground sloths. Darwin’s ground sloth (Mylodon darwini) was a mega mammal widely distributed in the Neotropics; however, its parasitic fauna is poorly known with the sole report of unidentified nematode eggs. Thus, this study aimed to determine additional host-parasite associations and to discuss its possible role as a reservoir of zoonotic parasites. Fifty-two coprolites from Cueva del Milodon Natural Monument were analyzed through coprological analysis to determine the presence of parasites. From these, 18 (34.62%) coprolites had parasitic helminth eggs belonging to 6 taxa: Calodium sp., Ascaridida, Hymenolepididae, Anoplocephalidae, Taeniidae, and Digenea. All these findings are new records for this sloth; also, two of them, Calodium sp. and Anoplocephalidae, have represented a risk for the health of ancient humans. Eggs of Calodium were similar to those previously isolated from ancient humans in Patagonia. Thus, Darwin’s ground sloth has represented a potential reservoir of zoonotic helminths, which is interesting considering this species was in close contact with humans in ancient Patagonia. Thus, additional collaboration with paleontologists is highlighted considering the incipient development of paleoparasitology in Chile, which could elucidate the presence of important pathogens, contributing to a better understanding of the evolution and changes in the distribution and virulence of certain parasites through time.

In general, large mammal species with highly specialized feeding behavior and solitary habits are expected to suffer genetic consequences from habitat loss and fragmentation. To test this hypothesis, we analyzed the genetic diversity distribution of the threatened giant anteater inhabiting a human-modified landscape. We used 10 microsatellite loci to assess the genetic diversity and population structure of 107 giant anteaters sampled in the Brazilian Central-Western region. No genetic population structuring was observed in this region suggesting no gene flow restriction within the studied area. On the other hand, the moderate level of genetic diversity (Ho = 0.54), recent bottleneck detected and inbreeding (Fis, 0.13; p ≤ 0.001) signatures suggest potential impacts on the genetic variation of this Xenarthra. Additionally, a previous demographic reduction was suggested. Thus, considering the increased human-promoted impacts across the entire area of distribution of the giant anteater, our results can illustrate the potential effects of these disturbances on the genetic variation, allowing us to request the long-term conservation of this emblematic species.

Xenarthra is an endemic South American lineage of mammals, probably the sister clade of the other placental mammals. The oldest records of Xenarthra are from the latest Paleocene, although its current diversity is much lower than that recorded in some intervals of the Cenozoic Era. A new Neogene Xenarthra (Pilosa and Cingulata) assemblage from two localities of the Argentine Eastern Puna (Calahoyo and Casira) is described. The newly recorded taxa—Cingulata, Dasypodidae, Eutatini: Stenotatus sp. indet. and Eutatini indet., Euphractini: Macrochorobates scalabrinii (Moreno and Mercerat, 1891), and Tardigrada, Mylodontinae: cf. Simomylodon sp. indet. and Simomylodon cf. S. uccasamamensis Saint-André et al., 2010—and those already published from Calahoyo—Cingulata: Macrochorobates chapadmalensis (Ameghino, 1908), Eosclerocalyptus sp. indet., and Tardigrada, Megatheriidae: Pyramiodontherium bergi (Moreno and Mercerat, 1891)—suggest a middle–late Miocene age for the fossil-bearing levels. In Calahoyo, the presence of Stenotatus sp. indet., in addition to some rodents currently under study in the lower levels, suggest a closer similarity with the palaeofauna of Cerdas (southern Bolivia), probably involving the last part of the Miocene Climatic Optimum. The Xenarthra recorded in the middle and upper levels of Calahoyo and Casira suggest a late Miocene–Pliocene age. A comparative analysis between Calahoyo and Casira highlights the absence of Cingulata in the latter and a high diversity in the former. This situation probably indicates different paleoenvironmental conditions. Finally, we present the first certain record of the genus Simomylodon Saint-André et al., 2010 in Argentina, which includes the oldest record of dermal ossicles for sloths in South America.

Distress calls are signals given by individuals experiencing physical stress such as handling by a predator. These calls have been recorded in numerous phylogenetically distant vertebrate species, and share certain acoustic features, such as high amplitude, broadband, and rich harmonic structure. Screaming hairy armadillos (Chaetophractus vellerosus) sometimes give a high-amplitude weeping call when captured by predators or disturbed by humans. We provide an acoustic characterization of this call using recordings of hand-held wild individuals, and test whether it constitutes a distress signal. The weeping call was a harsh, loud, broadband, long sound, composed of five note types: crying, inhaled, inhaled sobbing, exhaled sobbing, and grunt notes. Crying notes were the most common, distinctive, and loudest sounds. The proportion of armadillos that called when disturbed was between nearly five to seven times higher than when treated with care. Likewise, 223 hunters reported armadillos consistently weeping when trapped by dogs, and no weeping was heard in natural undisturbed conditions. Our data support a distress signal role for the weeping call. Las vocalizaciones de pánico son señales producidas por individuos cuando se encuentran en contextos de estrés físico, como ser capturados por un depredador. Estas vocalizaciones se han registrado en numerosas, y filogenéticamente distantes, especies de vertebrados, y las mismas comparten varias características acústicas, como alta amplitud, banda ancha y una rica estructura armónica. Los piches llorones (Chaetophractus vellerosus) son armadillos que a menudo emiten una fuerte vocalización llorosa cuando son capturados por depredadores o perturbados por humanos. En este trabajo caracterizamos acústicamente esta vocalización llorosa a partir de grabaciones realizadas en individuos libres que fueron capturados momentáneamente, y evaluamos si corresponde a una vocalización de pánico. La vocalización llorosa fue de larga duración y estuvo compuesta por sonidos ásperos, fuertes y de banda ancha. La misma no presentó dimorfismo sexual y se identificaron cinco tipos de notas: lloradas, inhaladas, sollozas inhaladas, sollozas exhaladas y graznidos. Las notas lloradas fueron los sonidos predominantes, distintivos y de mayor amplitud de la vocalización. La proporción de piches llorones que vocalizaron cuando fueron capturados y perturbados fue entre cinco y siete veces mayor que cuando fueron manipulados con cuidado. Del mismo modo, 223 cazadores informaron que los piches llorones comúnmente emiten vocalizaciones llorosas cuando estos son capturados por perros, y esta vocalización no fue producida por individuos que se encontraban libres en condiciones naturales inalteradas. Nuestros datos respaldan designar a la vocalización llorosa como una vocalización de pánico. Fil: Amaya, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; Argentina Fil: Zufiaurre, Emmanuel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Grupo de Estudios sobre Biodiversidad en Agroecosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Areta, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Abba, Agustin Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina

Xenarthra (sloths, anteaters, and armadillos) are the quintessential South American mammals. Among the xenarthrans, sloths constitute the most diverse paleontologically with almost 100 fossil genera recorded. However, this abundant sloth fauna in the Americas became extinct around 10,000 years ago. Only six species belonging to two genera, Bradypus (four three-toed sloth species) and Choloepus (two two-toed sloth species) are alive today in Central and South America. Bradypus variegatus is the sloth species with the widest geographical distribution in the Neotropics. Some regional population genetics have been reported, especially in Brazil, but with limited sample sizes. Herein, we sequenced 77 samples of Bradypys variegatus (Panama, Colombia, Venezuela, Peru, Bolivia, and Brazil; 65 new samples and 12 from GenBank), plus one B. tridactylus, one B. pygmaeus, and five B. torquatus (one new and four from GenBank) at the mitochondrial (mt) control region. Additionally, 25 of these samples, representing the four species, were sequenced for the entire mitochondrial genome. Our results indicate that there are at least six main genetically different haplogroups of B. variegatus. They are the trans-Andean, western Amazon (with some other internal groups), Tapajos River, Tocantins River, Negro River, and the Brazilian eastern Atlantic forest (with two recognizable sub-groups in northern and southern areas) ones, with the ancestor of the trans-Andean haplogroup the first to diverge. A very strong genetic heterogeneity and a striking spatial pattern were detected among these different geographical areas, with the trans-Andean, western Amazon, and Tocantins populations showing the highest levels of genetic diversity, meanwhile the Tapajos and the Brazilian eastern populations yielding lower levels of genetic diversity. The following conclusions were as follows: 1) B. torquatus should be considered as a different genus (Scaeopus) because of its extreme genetic differences from other Bradypus taxa as was previously claimed by other authors; 2) B. pygmaeus is not a recent species adapted to Holocene island environments from the Central America B. variegatus group; and 3) if we adopt a strict version of the Phylogenetic Species Concept (PSC), the highly significant monophyletic clade of the trans-Andean B. variegatus population should be defined as a valid and differentiated species of three-toed sloth. However, we are reluctant to define this population as a new species until new data shows possible strong karyotype differences and/or pre- or post-zygote reproductive barriers (Biological Species Concept, BSC) between the trans and the cis-Andean populations of the three-toed brown-throated sloth.

Glossotherium phoenesis sp. nov. from the late Pleistocene of intertropical Brazil is described and compared with Glossotherium robustum and Glossotherium tropicorum. Compared to these two species,...

The use of diagnostic methods that prevent irreplaceable samples (from museum collections, archaeological and paleontological samples) of being consumed or that increase their yield is relevant. For museum collections, archaeological and paleontological samples it is essential to conserve samples, subsamples or portions for future research. We are addressing methods for conservation of irreplaceable samples that could be fully consumed. Innovations in methodologies that are used in studies of Paleoparasitology and Paleomicrobiology will contribute to the preservation of collections. Therefore, to the development of archaeology and paleontology in the future, we evaluated whether the discarded material of the immunochromatography test could be used for molecular diagnosis and vice versa. We used a genotyped experimental coprolite positive for Giardia duodenalis. The diagnosis was positive for giardiasis in both cases. This methodology can be corroborated with the coprolite of a Paleolama maior (extinct llama) previously diagnosed for G. duodenalis with an immunoenzymatic test. The residue of the pre-digestion step of the DNA extraction before adding Proteinase K was confirmed positive with the immunochromatographic test. Also, the DNA extraction residue from a coprolite of Nothrotherium maquinense (ground sloth) was tested positive with immunochromatographic test for G. duodenalis. These are the oldest findings for G. duodenalis confirming that this intestinal parasite occurred among Northeastern Brazilian Megafauna animals from the late Pleistocene period, correlated to human occupation. The relevance of these results will allow the study by different methodological approaches from a small amount of material, reusing discarded materials.

Wild animals infected with Paracoccidioides brasiliensis represent important indicators of this fungal agent presence in the environment. The detection of this pathogen in road-killed wild animals has shown to be a key strategy for eco-epidemiological surveillance of paracoccidioidomycosis (PCM), helping to map hot spots for human infection. Molecular detection of P. brasiliensis in wild animals from PCM outbreak areas has not been performed so far. The authors investigated the presence of P. brasiliensis through nested-PCR in tissue samples obtained from road-killed animals collected nearby a human PCM outbreak spot, Rio de Janeiro state, Brazil and border areas. Eighteen species of mammals were analyzed: Dasypus novemcinctus (nine-banded armadillo, n = 6), Cerdocyon thous (crab-eating fox, n = 4), Coendou spinosus (hairy dwarf porcupine, n = 2), Lontra longicaudis (Neotropical river otter, n = 1), Procyon cancrivorus (crab-eating raccoon, n = 1), Galactis cuja (lesser grison, n = 1), Tamandua tetradactyla (collared anteater, n = 1), Cuniculus paca (paca, n = 1), and Bradypus variegatus (brown-throated three-toed sloth, n = 1). Specific P. brasiliensis sequences were detected in the liver, spleen, and lymph node samples from 4/6 (66.7%) D. novemcinctus, reinforcing the importance of these animals on Paracoccidioides ecology. Moreover, lymph nodes samples from two C. thous, as well as lung samples from the C. paca were also positive. A literature review of Paracoccidioides spp. in vertebrates in Brazil indicates C. thous and C. paca as new hosts for the fungal pathogen P. brasiliensis.

Background Leprosy is an infectious disease caused by Mycobacterium leprae. As incidence begins to decline, the characteristics of new cases shifts away from those observed in highly endemic areas, revealing potentially important insights into possible ongoing sources of transmission. We aimed to investigate whether transmission is driven mainly by undiagnosed and untreated new leprosy cases in the community, or by incompletely treated or relapsing cases. Methodology/Principal findings A literature search of major electronic databases was conducted in January, 2020 with 134 articles retained out of a total 4318 records identified (PROSPERO ID: CRD42020178923). We presented quantitative data from leprosy case records with supporting evidence describing the decline in incidence across several contexts. BCG vaccination, active case finding, adherence to multidrug therapy and continued surveillance following treatment were the main strategies shared by countries who achieved a substantial reduction in incidence. From 3950 leprosy case records collected across 22 low endemic countries, 48.3% were suspected to be imported, originating from transmission outside of the country. Most cases were multibacillary (64.4%) and regularly confirmed through skin biopsy, with 122 cases of suspected relapse from previous leprosy treatment. Family history was reported in 18.7% of cases, while other suspected sources included travel to high endemic areas and direct contact with armadillos. None of the countries included in the analysis reported a distinct increase in leprosy incidence in recent years. Conclusions/Significance Together with socioeconomic improvement over time, several successful leprosy control programmes have been implemented in recent decades that led to a substantial decline in incidence. Most cases described in these contexts were multibacillary and numerous cases of suspected relapse were reported. Despite these observations, there was no indication that these cases led to a rise in new secondary cases, suggesting that they do not represent a large ongoing source of human-to-human transmission., Author summary Although leprosy remains a public health problem in many parts of the world, several countries have successfully controlled the Mycobacterium leprae transmission over recent decades and the case characteristics have been shown to change during periods of declining incidence. However, the potential for certain groups of individuals, such as untreated or relapsed leprosy patients with more severe forms of the disease, to act as sources of ongoing transmission remains unclear. In this systematic review, we aimed to evaluate leprosy case characteristics in low endemic settings, to identify possible sources of transmission and to describe the different control measures implemented. Together with socioeconomic improvement over time, the main strategies shared by many of the countries who achieved a substantial reduction in incidence over recent decades included BCG vaccination, active case finding, adherence to MDT and continued surveillance following treatment. By collecting information on cases in these settings, we found that the number of new cases reported remained low with no indication of a rise in new secondary cases, despite a high proportion of multibacillary disease and the presence of persistent cases of suspected relapse. This evidence suggests that such cases do not represent a large ongoing source of human-to-human transmission.

We present carbon (δ13Ccollagen = -10.1 ‰) and nitrogen (δ15N = 6.8 ‰) isotopic data for E. laurillardi from Brejo da Madre de Deus, Pernambuco (Brazil) and discuss the possibility of an omnivore diet for it. Our data, although ponctual, reinforce the hypothesis that E. laurillardi was a herbivore species.

In Argentina, quantitative information on the composition and structure of assemblages of arthropod parasites in Xenarthra is scarce. The aim of this study was to describe and compare the community of arthropod parasites of Chaetophractus villosus and Zaedyus pichiy in the Argentinean Patagonia. A total of 1300 ectoparasites (1224 fleas and 76 ticks) were collected from both host species. Seven different species were found, namely Phthiropsylla agenoris, Malacopsylla grossiventris, Hectopsylla broscus, Tunga penetrans, Tunga perforans (Siphonaptera), Amblyomma pseudoconcolor and Amblyomma auricularium s.l. (Ixodida). Four species were present in both host armadillos (P. agenoris, M. grossiventris, H. broscus and A. pseudoconcolor). Phthiropsylla agenoris was the most prevalent and abundant ectoparasite showing significant differences in prevalences, mean intensities and mean abundance. Malacopsylla grossiventris only showed significant differences in mean intensity. The structure and composition of the ectoparasite assemblage and the high values of ectoparasites aggregation recorded in the Patagonian armadillos strongly suggest that these associations are stable throughout their geographical distribution.

Pseudoextinction analyses, which simulate extinction in extant taxa, use molecular phylogenetics to assess the accuracy of morphological phylogenetics. Previous pseudoextinction analyses have shown a failure of morphological phylogenetics to place some individual placental orders in the correct superordinal clade. Recent work suggests that the inclusion of hypothetical ancestors of extant placental clades, estimated by ancestral state reconstructions of morphological characters, may increase the accuracy of morphological phylogenetic analyses. However, these studies reconstructed direct hypothetical ancestors for each extant taxon based on a well-corroborated molecular phylogeny, which is not possible for extinct taxa that lack molecular data. It remains to be determined if pseudoextinct taxa, and by proxy extinct taxa, can be accurately placed when their immediate hypothetical ancestors are unknown. To investigate this, we employed molecular scaffolds with the largest available morphological data set for placental mammals. Each placental order was sequentially treated as pseudoextinct by exempting it from the molecular scaffold and recoding soft morphological characters as missing for all its constituent species. For each pseudoextinct data set, we omitted the pseudoextinct taxon and performed a parsimony ancestral state reconstruction to obtain hypothetical predicted ancestors. Each pseudoextinct order was then evaluated in seven parsimony analyses that employed combinations of fossil taxa, hypothetical predicted ancestors, and a molecular scaffold. In treatments that included fossils, hypothetical predicted ancestors, and a molecular scaffold, only 8 of 19 pseudoextinct placental orders (42%) retained the same interordinal placement as on the molecular scaffold. In treatments that included hypothetical predicted ancestors but not fossils or a scaffold, only four placental orders (21%) were recovered in positions that are congruent with the scaffold. These results indicate that hypothetical predicted ancestors do not increase the accuracy of pseudoextinct taxon placement when the immediate hypothetical ancestor of the taxon is unknown. Hypothetical predicted ancestors are not a panacea for morphological phylogenetics.

The similarity between parasites communities’ decay with distance and its analysis may explain important ecological process such host dispersion. Patagonia is inhabited by two armadillo species, Chaetophractus villosus and Zaedyus pichiy. In this study we describe and analyze the variation on helminth fauna of these armadillos in Patagonia compared with northern localities described in previous studies. A total of 49 armadillos were collected in Patagonia. Quantitative descriptors of parasite ecology were calculated and community structure of helminths was analyzed following the central-satellite species hypothesis. The parasite richness in Patagonia decreases almost 50% in both armadillos. Zaedyus pichiy present the same central species in Patagonia as in northern localities. For C. villosus central-satellite species analysis could not be applied. The loss of some helminths in Z. pichiy could be the result of lower temperatures or the absence of intermediate arthropods hosts. But in C. villosus the absence of some helminths with Patagonian distribution could be explained by its recent dispersion in Patagonia. Trichohelix tuberculata still being the only helminth in C. villosus introduced population of Tierra del Fuego.

Descriptions of myology reflect adaptations of the post-cranium and are essential for understanding the functional morphology of animal limbs. Armadillos (Cingulata) are the most species-rich group of the basal superorder Xenarthra, which is evident by their various lifestyles (subterranean vs. terrestrial) and levels of fossoriality (fossorial vs. semi-fossorial). While there have been several studies on limb bone proportions in numerous armadillos, limb myology has been reported for a limited number of species. Many of these descriptions need updating, and detailed quantitative muscle data are available only for nine-banded armadillos. The main objective of this study is to assess the forelimb myology of the pichi (Zaedyus pichiy), screaming hairy (Chaetophractus vellerosus), large hairy (Chaetophractus villosus), and pink fairy (Chlamyphorus truncatus) armadillos with comparisons to previous observations to specify muscle traits that indicate scratch-digging specializations in cingulates. Several myological features are variable among the species studied, including the origin of m. trapezius pars cervicalis, presence of a distinct m. rhomboideus profundus and m. omotransversarius, and number of heads present for m. triceps brachii and m. flexor digitorum profundus, all of which can be associated with variability in their respective habitats and functional habits. These traits are consistently observed in the members of the Euphractinae, whereas they are slightly divergent (i.e., reduced complexity) in the pink fairy armadillo despite a similar distribution of muscle mass in the limb retractors, elbow extensors, and carpal/digital flexors across species. The ecomorphology observed here among cingulates also confirms their recent reorganization into separate families and subfamilies.

Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) and the more recently discovered Mycobacterium lepromatosis (M. lepromatosis). The two leprosy bacilli cause similar pathologic conditions. They primarily target the skin and the peripheral nervous system. Currently it is considered a Neglected Tropical Disease, being endemic in specific locations within countries of the Americas, Asia, and Africa, while in Europe it is only rarely reported. The reason for a spatial inequality in the prevalence of leprosy in so-called endemic pockets within a country is still largely unexplained. A systematic review was conducted targeting leprosy transmission research data, using PubMed and Scopus as sources. Publications between January 1, 1945 and July 1, 2019 were included. The transmission pathways of M. leprae are not fully understood. Solid evidence exists of an increased risk for individuals living in close contact with leprosy patients, most likely through infectious aerosols, created by coughing and sneezing, but possibly also through direct contact. However, this systematic review underscores that human-to-human transmission is not the only way leprosy can be acquired. The transmission of this disease is probably much more complicated than was thought before. In the Americas, the nine-banded armadillo (Dasypus novemcinctus) has been established as another natural host and reservoir of M. leprae. Anthroponotic and zoonotic transmission have both been proposed as modes of contracting the disease, based on data showing identical M. leprae strains shared between humans and armadillos. More recently, in red squirrels (Sciurus vulgaris) with leprosy-like lesions in the British Isles M. leprae and M. lepromatosis DNA was detected. This finding was unexpected, because leprosy is considered a disease of humans (with the exception of the armadillo), and because it was thought that leprosy (and M. leprae) had disappeared from the United Kingdom. Furthermore, animals can be affected by other leprosy-like diseases, caused by pathogens phylogenetically closely related to M. leprae. These mycobacteria have been proposed to be grouped as a M. leprae-complex. We argue that insights from the transmission and reservoirs of members of the M. leprae-complex might be relevant for leprosy research. A better understanding of possible animal or environmental reservoirs is needed, because transmission from such reservoirs may partly explain the steady global incidence of leprosy despite effective and widespread multidrug therapy. A reduction in transmission cannot be expected to be accomplished by actions or interventions from the human healthcare domain alone, as the mechanisms involved are complex. Therefore, to increase our understanding of the intricate picture of leprosy transmission, we propose a One Health transdisciplinary research approach., Author summary Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) and the more recently discovered Mycobacterium lepromatosis (M. lepromatosis). The two leprosy bacilli cause similar stigmatizing pathologic conditions. M. leprae primarily targets the skin and the peripheral nervous system. Currently it is considered a Neglected Tropical Disease. The transmission pathways of M. leprae are not fully understood. Solid evidence exists of an increased risk for individuals living in close contact with leprosy patients, most likely through infectious aerosols, created by coughing and sneezing, but possibly also through direct contact. However, this systematic review underscores that human-to-human transmission is not the only way leprosy can be acquired. Anthroponotic and zoonotic transmission have both been proposed as modes of contracting the disease, based on data showing identical M. leprae strains shared between humans and armadillos. A better understanding of possible animal or environmental reservoirs is needed, because transmission from such reservoirs may partly explain the steady global incidence of leprosy despite effective and widespread multidrug therapy. Reducing transmission cannot be expected from the human healthcare domain alone, as the mechanisms involved are complex. Therefore, we propose a One Health transdisciplinary research approach.

Anaplasmataceae agents are obligatory intracellular Gram-negative α-proteobacteria that are transmitted mostly by arthropod vectors. Although mammals of the Superorder Xenarthra (sloths, anteaters, and armadillos) have been implicated as reservoirs for several zoonotic agents, only few studies have sought to detect Anaplasmataceae agents in this group of mammals. This study aimed to investigate the occurrence and genetic diversity of Anaplasma spp. and Ehrlichia spp. in blood and spleen samples of free-living Xenarthra from four different states in Brazil (São Paulo, Mato Grosso do Sul, Rondônia, and Pará). Nested and conventional PCR screening assays were performed to detect the rrs and dsb genes of Anaplasma spp. and Ehrlichia spp., respectively. The assays were positive in 27.57% (91/330) of the Anaplasma spp. and 24.54% (81/330) of the Ehrlichia spp. Of the 91 positive Anaplasma spp. samples, 56.04% were positive in a conventional PCR assay targeting the 23S–5S intergenic region. Phylogenetic and distance analyses based on the rrs gene allocated Anaplasma sequences from sloths captured in Rondônia and Pará states in a single clade, which was closely related to the A. marginale, A. ovis, and A. capra clades. The sequences detected in southern anteaters from São Paulo were allocated in a clade closely related to sequences of Anaplasma spp. detected in Nasua nasua, Leopardus pardalis, and Cerdocyon thous in Brazil. These sequences were positioned close to A. odocoilei sequences. Genotype analysis corroborated previous findings and demonstrated the circulation of two distinct Anaplasma genotypes in animals from north and southeast Brazil. The first genotype was new. The second was previously detected in N. nasua in Mato Grosso do Sul state. The intergenic region analyses also demonstrated two distinct genotypes of Anaplasma. The sequences detected in Xenarthra from Pará and Rondônia states were closely related to those in A. marginale, A. ovis, and A. capra. Anaplasma spp. sequences detected in Xenarthra from São Paulo and were allocated close to those in A. phagocytophilum. The analyses based on the dsb gene grouped the Ehrlichia spp. sequences with sequences of E. canis (São Paulo, Mato Grosso do Sul, and Pará) and E. minasensis (Rondônia and Pará). The data indicate the occurrence of E. canis and E. minasensis and two possible new Candidatus species of Anaplasma spp. in free-living mammals of the Superorder Xenarthra in Brazil.

In this study, the first records of lesions in osteoderms of Holmesina, a group of fossil cingulates related to armadillos, possibly caused by the action of penetrating fleas (Siphonaptera) are described. Three individuals of Holmesina cryptae (Pampatheriidae) were collected from Quaternary sediments in Lapinha Cave (Iramaia, Bahia state, Brazil). Their osteoderms were analyzed by stereomicroscope and scanning electron microscopy and alterations on their surfaces were recognized. We found 63 marks distributed in 23 of 1300 analyzed osteoderms (approximately 1.8% of the total of osteoderms), characterized by vertical cavities with well-delimited circular borders similar to those lesions made by Tungidae fleas in extant mammals. These records indicate that there was an interaction between penetrating fleas and pampatheres during the Quaternary in Brazilian Intertropical Region, and contribute to the understanding of the evolution of these ectoparasites and the relationship with their hosts.

The late Pleistocene mylodontine sloth Glossotherium wegneri (Spillmann, 1931) (Interandean ­region, Ecuador) has been assigned to Glossotherium Owen, 1839 and Oreomylodon Hoffstetter, 1949 (the latter ranked as a subgenus or genus), and synonymized with G. robustum (Owen, 1842). However, the phylogenetic and comparative analyses conducted here, which include previously undescribed remains, strongly suggest specific distinction for G. wegneri and that there is little, if any, support for generic or subgeneric distinction for Oreomylodon. Among the notable features of this species are the ­presence of an internasal element, marked expansion of the rostrum anteriorly, and dorsoventrally and the palatal region transversely, increased separation of the caniniform tooth from the anterior edge of maxilla, increased relative braincase width, relatively enlarged hypoglossal foramen, and greatly elongated zygomatic process of the squamosal. The resulting single MPT recovered a monophyletic Glossotherium, with the following phylogenetic arrangement of the species of this genus (G. robustum + ((G. wegneri + G. tropicorum Hoffstetter, 1952) + (G. phoenesis Cartelle, De Iuliis, Boscaini & Pujos, 2019 + G. tarijense Ameghino, 1902))).

The relationship between humerus shape and the modes of exploring substrate among extinct and extant Pilosa (especially anteaters and ground sloths) were investigated here. We used geometric morphometrics and discriminant analyses to relate morphological patterns and their possible ecological categories. Our results suggest that plesiomorphic taxa such as Nothrotheriidae, most Megalonychidae and basal Megatheriidae tend to have more slender humerus, associated to generalist habitus (climbing, swimming and digging activities), and while Mylodontidae developed specialized digging habitus. Additionally, we inferred ground sloths which inhabited the Brazilian territory during the Quaternary likely occupied at least four different niches. Mammals display morphofunctional adaptations on the limbs which are reflected on their modes of substrate exploration. Herein, we analyzed the humerus morphology of ground sloths and anteaters. Our results suggest that most of the Pleistocene Mylodonts were fossorial taxa, while most of the Santacrucian sloths plus extant anteaters were semiarboreal or semiaquatic taxa. The Pleistocene Megatheriidae should be ambulatory.

Glyptodon and Glyptotherium represent the most conspicuous taxa of late Neogene and Pleistocene glyptodonts in South America and North America, respectively. The earliest records of Glyptodon in South America are 1.07 Ma (late early Pleistocene, Calabrian), although the possibility that “Paraglyptodon uquiensis” represents a Pliocene specimen of Glyptodon cannot be rejected. Glyptotherium originated from South American ancestry in northern South America or Central America about 3.9 Ma (early late Pliocene, Zanclean) or earlier. The diversity of South American Glyptodon is currently under study, but preliminary evidence would indicate that no more than three species (G. munizi, G. elongatus and G. reticulatus) are valid, plus a possible new Andean species. In turn, according to the updated taxonomy proposed herein, Glyptotherium includes two chronospecies. The earliest species, Gl. texanum, differs only slightly from the latest species, Gl. cylindricum. The relationship of Glyptodon and Glyptotherium has been problematical since the discovery of the North American lineage, at first identified as various species of Glyptodon and later considered a separate genus. Glyptodon is recognized as a natural group and recent taxonomic and phylogenetic revisions place all North American glyptodontines into Glyptotherium. In this paper, we propose a detailed morphological comparison between the southern South American species of Glyptodon and Glyptotherium in order to identify diagnostic differences and potential synapomorphies. Both genera can be distinguished mainly by differences in the skull, mandible, dentition, dorsal carapace, and caudal armor, Glyptodon being somewhat larger than Glyptotherium. Both clades show a highly conservative evolution, which could be interpreted as an anagenesis. The scarce records of glyptodonts in Central America show more morphological affinity with Glyptotherium than with Glyptodon. Fil: Zurita, Alfredo Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Gillette, David D.. Museum of Northern Arizona; Estados Unidos Fil: Cuadrelli, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Carlini, Alfredo Armando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina

Pangolins are a group of eight endangered mammalian species included in the family Manidae (Order Pholidota) and divided into four each African (Arboreal species; Phataginus tetradactyla, Phataginus tricuspis, Ground dwelling species; Smutsia gigantea and Smutsia temminckii) and Asian (Ground dwelling; Manis crassicaudata, Manis pentadactyla, Manis javanica and Manis culionensis) species. The taxonomy of all the eight extant pangolin species based on molecular genetics studies, remains unresolved and poorly examined. The present study is to address this lacuna by studying the phylogenetic, taxonomic status and molecular dating of Indian pangolin with other six out of eight extant pangolins (Sunda pangolin possibly extinct) based on complete coding region of mitochondrial cytochrome b gene. Overall sequences divergence among pangolins ranged between 0.01 ± 0.01 and 0.26 ± 0.03, where within 'Manis' it ranged between 0.01 ± 0.01 and 0.14 ± 0.03. Cytochrome b sequences based phylogenetic tree revealed, the division of seven pangolin species into two paraphyletic clades of African and Asian species, further these two paraphyletic clades were divided into three well-supported monophyletic clades, first for the genus 'Smutsia' with two African ground pangolins, second for the genus 'Phataginus' with two African arboreal pangolins and third for 'Manis' with three Asian species. Within clade of 'Manis', Chinese pangolin and Malayan pangolin are basal where Indian pangolin is present as a sister clade and furthermore, molecular dating analysis suggested that pangolins diverged from Carnivora at ∼87.2 MYA, followed by the split of Asian pangolins and African pangolins at ∼36.1 MYA and Indian pangolin split from Chinese pangolin and Malayan pangolin at ∼16.7 MYA.

Xenarthra is one of the most peculiar mammalian groups to have originated in South America, where most of its evolutionary history has taken place. Xenarthrans have experienced significant climatic changes and also geographical isolation for most of the Cenozoic. Thus, the cranial morphology of xenarthrans may reflect the different pressures that the group is currently undergoing. Our objective is to identify the drivers of phenotypic variation of the skull (both shape and size) in widespread representatives of the superorder Xenarthra throughout South America. We tested the influence of allometry and neutral and niche processes on three extant species, using a geometric morphometric approach: the three-toed sloth Bradypus variegatus, the lesser anteater Tamandua tetradactyla, and the armadillo Dasypus novemcinctus. Our results show that allometry is present, but has a weak effect on shape variation. Geography has a greater impact than allometry in explaining the size variation of T. tetradactyla and the shape of B. variegatus which is, interestingly, the only studied species that follows Bergmann’s rule. Most importantly, the environment drives most of the variation in the shape and size of the three species studied. The responses of B. variegatus and T. tetradactyla to geographical space are congruent with their low mobility and more limited dispersal. The environment mainly affected B. variegatus (e.g., following Bergmann’s rule), probably because of its particularly low metabolism, and D. novemcinctus, due to its high dispersal capacity.