DOI: 10.3897/vz.76.e173627

Authors: Diego A. Caraballo, Denise H. Campo, Pablo Teta, Cecilia Lanzone

Abstract: Abstract Species delimitation in recently evolving taxa presents unique challenges. Such taxa may not have accumulated enough genetic or morphological differences to be easily distinguished using traditional methods, while processes such as incomplete lineage sorting or gene flow may obscure these distinctions. One paradigmatic recently evolved taxon is the Corrientes group of the subterranean genus Ctenomys (Rodentia, Ctenomyidae), a set of populations with different chromosomal forms occurring in the homonymous province of Argentina. Previously, three nominal species and several independently evolving lineages had been proposed; however, a comprehensive integrative approach—including qualitative and quantitative morphological analyses, as well as additional molecular proxies for lineage delimitation—was still lacking, and these results had not been evaluated in a taxonomic context. In this study, we added new lines of evidence, including Bayesian phylogenetics and divergence time estimation, haplotype networks, and genetic distances. We integrated this information with karyotypic and microsatellite data to discuss previously proposed lineages, as well as to analyze the evolutionary processes that shaped the history of this group. Finally, we analyzed the qualitative and quantitative morphology of individuals from the nominal species and a chromosomally derived lineage, and we propose a revised species-level and infraspecific classification for this complex group of rodents. This resulted in the delimitation of two species, C. roigi and C. perrensi, the latter being subdivided into three subspecies: Ctenomys perrensi perrensi, C. perrensi dorbignyi, and C. perrensi iberaensis subsp. nov. In addition, other identified lineages, such as Sarandicito, Manantiales, and Santa Rosa, deserve future taxonomic investigation.

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DOI: 10.3897/vz.76.e180973

Authors: Oleg V. Brandler, Andrey R. Tukhbatullin, Svetlana Y. Kapustina, Sergey N. Matveevsky, Fatimat A. Tembotova, Andrey Y. Puzachenko

Abstract: Abstract The systematics of blind mole rats (Spalacinae), a group of highly specialized subterranean rodents, remain a subject of debate. Within the genus Spalax, the greater blind mole rat (Spalax microphthalmus) is distinguished by its unique diploid chromosome number (2n = 60 versus 2n = 62 in others) and the most extensive geographic range. However, its intraspecific variation has been insufficiently studied. Previous finding of specimens with 2n = 62 in the North Caucasus were attributed to chromosomal polymorphism within S. microphthalmus. In this study, we conducted a comprehensive analysis of morphometric, morphological, molecular, and chromosomal variation across the entire range of S. microphthalmus, integrated with a comparative analysis of the genus Spalax. Our results demonstrate that the North Caucasian populations (2n = 62) exhibit consistent species-level differences in molecular genetics (from 8% to 12% divergence in cyt b), karyotype, and cranial morphology, distinguishing them from S. microphthalmus and all other congeners. This lineage also possesses a unique combination of morphological traits, including features that bring it closer to the hypothetical common ancestor of all modern Spalax species. Based on this integrative evidence, we describe this lineage as a new species: Spalax lyapunovae sp. nov., increasing the number of extant Spalax species to nine. This newly recognized species, endemic to the central North Caucasus, requires further ecological and distributional studies. Given its presumably limited range, an urgent assessment of its conservation status is warranted.

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DOI: 10.3897/vz.76.e182515

Authors: Kun-Hao Chen, Xiao-Yun Wang, Ze-Feng Huang, Yun-Zheng Mo, Yi Wu, Yi-Bo Hu, Yang Yue, Wen-Hua Yu

Abstract: Abstract The taxonomy of genus Myotis (Chiroptera: Vespertilionidae) has long posed considerable challenges, with numerous species in China remaining poorly defined. To address long-standing taxonomic ambiguities in Chinese Myotis, this study integrates over 15 years of fieldwork and conducts a comprehensive assessment of 197 specimens collected primarily in eastern China, which represent approximately 70% of the country’s known species. Molecular species delimitation, phylogenetic reconstruction, and multivariate analyses of morphological data were jointly employed to reassess species diagnostic traits. Phylogenetic and molecular delimitation supported the validity of 30 Myotis species in China, and resolved several long-debated complexes, including M. davidii, M. siligorensis, and M. frater. Principal component and hierarchical clustering analyses revealed mixed and overlapping patterns among species, particularly within small to medium size taxa. These results highlighted the limitations of traditional morphometric traits for distinguishing closely related Myotis. Initial classification accuracy using morphological traits alone was modest. However, when categorical phenotypic data was added into the dataset, model performance improved markedly: Random forest accuracy increased from 77.9% to 90.5%, and the decision tree model successfully discriminated 16 taxonomic units. These suggested that categorical phenotypic data can substantially enhance identification within morphologically conservative groups. Based on integrative evidence, we established an updated identification key. In addition, high-resolution 3D digital models of craniodental structures were generated to facilitate open access for future research. This study provided a foundation for subsequent phylogeny, ecology, and conservation biology studies on this taxonomically difficult genus.

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DOI: 10.3897/vz.76.e194570

Authors: Raquel Alvarado-Larios, Pablo Teta, Pablo Cuello, J. Pablo Jayat, Andrea P. Tarquino-Carbonell, Guillermo D'Elia, Paula Cornejo, Agustina A. Ojeda

Abstract: The genus Ctenomys Blainville, 1826 includes 68 living species of small to medium-sized (100-1200 g) caviomorph rodents of subterranean habits. During the last decade, this genus has been the subject of numerous taxonomic studies, including the description of new species and the proposal of novel synonyms. Based on phylogenetic analysis of mitochondrial DNA sequences and qualitative and quantitative morphological traits, here we review the species boundaries of the tuco-tucos of the species group of C. mendocinus and describe a new species. The new species is morphologically distinct from other phylogenetically and geographically close species of Ctenomys (e.g., C. fochi, C. mendocinus), showing several differences in their craniodental traits (e.g., proportionally longer nasals and less globose tympanic bullae). The new species occurs in montane grasslands and shrublands of northwestern Mendoza (ca. 2,710 m a.s.l.) and in lowlands (ca. 1,000 m a.s.l.) of the Monte Desert ecoregion in an area highly impacted by accelerated processes associated with the wine industry.

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DOI: 10.3897/vz.76.e194750

Authors: Uwe Fritz

Abstract: NO ABSTRACT

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DOI: 10.3897/vz.76.e194752

Authors: Uwe Fritz

Abstract: No Abstract

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DOI: 10.3897/vz.76.e180962

Authors: Nikoleta Dubjelová, Tereza Hadravová, Martin Ivanov, Ivan Horáček

Abstract: The European Pleistocene populations of the narrow-headed vole (Stenocranius gregalis), an index species of the Palearctic glacial communities, were recently found to differ from the extant Asian species by a deep genetic divergence and are to be considered a separate species, Stenocranius anglicus, which had to persist through the interglacial stages in local European refugia. Here, we analyze over 2000 first lower molars from 14 stratified localities in the Czech Republic and Slovakia, spanning the Middle Pleistocene to Holocene, employing geometric morphometrics, biometric measurements, and morphotype classifications to assess molar shape variation. Our results demonstrate persistent morphological variability, with particularly high morphotype diversity during MIS 5–3, followed by simplification and reduced variance in post–LGM populations. Morphological divergence was greater among geographic localities than stratigraphic stages, suggesting strong regional and ecological influences. Stratified sequences reveal diverse evolutionary trajectories from long-term morphological stability in refugia to gradual simplification preceding extinction in the early Holocene. These patterns align with broader Eurasian trends but also highlight regionally specific responses to climatic and ecological change accompanying the species’ extinction dynamics during the early to middle Holocene. The paper underscores the importance of integrating detailed morphometrics with stratigraphic and ecological evidence to shed light on these topics.

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DOI: 10.3897/vz.75.e153115

Authors: Anna A. Bannikova, Paulina D. Jenkins, Vladimir S. Lebedev, Svetlana V. Pavlova, Vasily D. Yakushov, Alexandra A. Raspopova, Yongke Zhu, Yun Fang, Yue-Hua Sun, Boris I. Sheftel

Abstract: Abstract The taxonomy of the stripe-backed shrew complex (Sorex cylindricauda species group), distributed in mountains of western China, appears challenging due to remarkable variation in morphological traits and relatively recent times of diversification. According to classical points of view only two or three species of the stripe-backed shrews can be distinguished. However, previous molecular reconstructions revealed at least 14 genetic lineages including a number of undescribed cryptic species. In the current study we revise the taxonomic status of large-sized stripe-backed shrews occurring in high mountain areas in south Gansu, north-western Sichuan and western Qinghai that were previously treated as S. aff. cylindricauda or S. sinalis. The available molecular data place them in a separate species-level lineage of the stripe-backed shrew complex. Our morphological analysis indicate that shrews of this lineage are distinct from the two other large-sized Chinese species, S. cylindricauda and S. sinalis, based on both cranial and external traits. Therefore, we here describe it as a species new to science, the karyotype of which is characterized by 2n = 26 with an additional B chromosome and NFa = 44. Our molecular phylogenetic analysis demonstrates multiple instances of mitonuclear discordance among lineages within the S. cylindricauda complex, which is likely a result of mtDNA introgression, thus highlighting the important role of reticulation events in the evolution of the group.

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DOI: 10.3897/vz.75.e148147

Authors: Andrey Y. Puzachenko, Viktor G. Yudin, Alexei V. Abramov

Abstract: Abstract Four species of Eurasian badgers (Meles) are widely distributed across Eurasia. Small-sized and dark-coloured Far Eastern M. leucurus amurensis is the most distinctive form among all Asian badgers, M. leucurus. Traditionally, Far Eastern badgers are treated as a subspecies of the M. leucurus. This study aims to revise the geographical variability of the M. leucurus sensu lato from the entire species range (324 adult skulls) and assess the position of the Far Eastern badgers. In addition, 551 adult skulls of the European badger, M. meles, the Southwest Asian badger, M. canescens, and the Japanese badger, M. anakuma, were used for comparison with Asian badgers. Meles leucurus amurensis from the Far East resembles the Japanese M. anakuma in many respects, but is very different from the M. l. leucurus of southern Siberia and Middle Asia. Analysis of palaeontological data suggests that the Far Eastern badgers could have descended from the ancestral “leucurus-like” badger chronospecies known from China since the mid-Early Pleistocene. It then probably dispersed westwards into southern Siberia no later than the MIS9 stage (~ 0.32 Ma), where it evolved into M. leucurus. Previous molecular data suggest that the Japanese badgers are unique, whereas the Far Eastern badgers are closer to Asian badgers from the Urals, Siberia and Tibet. We propose that the Far Eastern badger retains some craniometrics features of the ancestral form of M. leucurus sensu stricto and M. anakuma and should therefore be considered a separate species, M. amurensis Schrenck, 1859 stat. rev. The presumed range of this species is in the Far East, east of the Great Khingan Range to Russian Primorye, Manchuria and the Korean Peninsula and possibly eastern China.

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DOI: 10.3897/vz.75.e134683

Authors: Uliana V. Gorobeyko, Denis V. Kazakov, Anastasia A. Kadetova, Irina N. Sheremetyeva, Valentin Yu. Guskov, Irina V. Kartavtseva, Nikolai E. Dokuchaev, Evgeniy S. Zakharov, Sergei V. Kruskop

Abstract: Abstract Myotis petax is a common and widespread Asian bat species, whose intraspecific sequence variability remains poorly understood. In this work we analyzed the variability of the mitochondrial control region and craniometric measurements for an extensive sample set originating from the entire species range. This made it possible to identify the main genetic lineages and to compare their distribution with the morphological groups. From our investigations, we found that the prevalent genetic lineages, namely, “Siberia,” “Amur,” and “Okhotsk,” appear to be connected to large river systems. The cohabitation of various genetic lineages occurs only in territories where different river basins are connected, such as the Primorsky Territory, Khabarovsk Territory, Transbaikalia Territory, and Mongolia. Moreover, we discovered that the five morphological groups (Siberia, Okhotsk, Amur, Kunashir, and Korea) are partially correlated with previously identified genetic lineages and subspecies. However, M. p. petax and M. p. loukashkini were the only two out of the five subspecies that could be well-defined using specific mtDNA sequences and morphological descriptions. Nonetheless, the subspecies M. p. ussuriensis does not have a distinct genetic lineage to allow for their classification. Notably, a specific mix of morphological group and a genetic lineage characterize the “Amurian morphological form,” which may support its validity as a subspecies rank. That notwithstanding, more information is needed to fully unravel the intraspecific structure of M. petax in the southern Far East and potential contact zones of diverse forms.

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DOI: 10.3897/vz.74.e127269

Authors: Dorottya Győrössy, Vuong Tan Tu, Gábor Csorba, Sanjan Thapa, Péter Estók, Gábor Földvári, Tamás Görföl

Abstract: Abstract In taxonomic works, the weight to be given to morphological, mitochondrial, or nuclear signals, and the assessment of differences as species or subspecies distinctions has also varied considerably over the past decades and is largely a subjective research decision. This apparent example of the “grey zone of taxonomy” underpins the need of critical studies of as many specimens as possible and of using both mitochondrial and nuclear genes in taxonomic-systematic studies, as phylogeny based on uniparentally inherited genes alone may not represent true evolutionary scenarios. Myotis sicarius, a species occurring thorough the Himalayan foothills was found for the first time out of South Asia, in North Vietnam. Analysis of topotypical and Vietnamese specimens revealed high mitochondrial heterogeneity – at the upper limit of the usual threshold of intraspecific difference – but only minute nuclear sequence and negligible morphological differences. Albeit the large geographic distance between the two records might suggest the existence of two putative reproductively isolated taxonomic units, based on the incongruent results we concluded that the split of geographic populations of M. sicarius into different taxa is unsupported. As a morphologically closely resembling species, we also reviewed the taxonomic status of the two morphological forms of M. annectans and synonymizing M. primula with M. annectans was also corroborated by our phylogenetic analyses.

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DOI: 10.3897/vz.74.e144189

Authors: Uwe Fritz

Abstract: Editorial Expression of Concern

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DOI: 10.3897/vz.74.e128528

Authors: Jorge Brito, Rubí García, Francisco X. Castellanos, Gabriela Gavilanes, Jenny Curay, Julio C. Carrión-Olmedo, Daniela Reyes-Barriga, Juan M. Guayasamin, Jorge Salazar-Bravo, C. Miguel Pinto

Abstract: Abstract The Andean cloud forests of Ecuador are home to numerous unique mammals. Rodents of the tribe Thomasomyini are particularly abundant in many Andean localities, with Thomasomys – the largest genus in the subfamily Sigmodontinae (51 species) – especially species-rich and diverse. Despite recent advances on the systematics of the genus, where seven species have been described in the last five years, there is tantalizing evidence that its true diversity remains completely understood. Over the course of approximately ten years of fieldwork in Ecuador, a significant number of Thomasomys specimens were collected from various localities in both, the eastern and western Andean ranges. Through an extensive genetic study of these specimens, augmented with what is available in public databases, we argue that there exist at least 20 undescribed species in the genus, with no less that twelve potential new species in Ecuador alone. In this paper, we describe two of these species belonging to the group cinereus, one recently collected and the other previously referred to as Thomasomys sp. 1; further, we present an updated cyt b gene tree of the genus. The gene tree includes at least 56 valid and putative species and supports the monophyly of the genus, while at the same time suggest a paraphyletic “aureus” group. Our findings suggest that the genus likely exhibits additional hidden diversity in significant portions of Colombia, Peru, and Bolivia which calls for the need for a comprehensive reassessment of the entire genus. The recognition of these two new species brings the total number of known Thomasomys to 53 species, 19 of which occur in Ecuador, including 17 that are endemic to this country.

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DOI: 10.3897/vz.74.e133467

Authors: Arlo Hinckley, Jesús E. Maldonado, Noriko Tamura, Jennifer A. Leonard, Melissa T. R. Hawkins

Abstract: Abstract We present a comprehensive integrative taxonomic review of Callosciurus caniceps and Tamiops mcclellandii as they are currently defined. This review combines published molecular evidence, craniodental morphometrics, pelage and bacular variation, evaluations of potential hybrid zones using museum specimens and citizen science photographs, and, for C. caniceps, bioacoustic evidence. Our findings lead to the recognition of two species that had been lost in synonymy and highlight future perspectives on species delimitation in Sciuridae. By comparing phenotypic differentiation across climatic and vegetation transitions and contextualizing our results with the evolutionary history of our study systems, we provide insights into distribution, ecogeographical patterns, and speciation drivers in Southeast Asian vertebrates.

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DOI: 10.3897/vz.74.e126944

Authors: Franziska Wagner, Valerie Burke DeLeon, Christopher J. Bonar, Timothy D. Smith

Abstract: Abstract Comparative studies rely on the identification of homologous traits, which is challenging especially when adult stages alone are available. Inferring homology from developmental series represents the most reliable approach to recognize similar phenotypes. The primate nasal cavity exhibits a plastic morphology (shape) and topology (structure) which challenge the terminology of turbinals. Turbinal development largely corresponds to the therian template: turbinals emerge from the cartilaginous nasal capsule, ossify endochondrally, and increase their size through appositional bone growth. We studied histological serial sections and µCT data of eleven primate species in six genera representing four to five age stages (fetal to adult), and the neonate and adult stage of another primate species. We reconstructed cartilaginous precursors and followed their growth patterns until adulthood to inform the identification of structures. The developmental stages were transformed to character states for better comparison across the sample. Strepsirrhines conserved the plesiomorphic condition, with turbinal morphology similar to other placentals. In contrast, haplorhines showed a reduced turbinal number. Most strikingly, some cartilaginous turbinals are absent in the ossified nasal cavity (Saguinus); others seem to emerge as appositional bone without a cartilaginous precursor (Aotus, Pithecia). Our observation that successive developmental sequences differ from the established placental template emphasizes the significance of ontogenetic series for comparative anatomy. Structures which exhibit analogous growth patterns might be falsely considered as being homologous in adults, resulting in biased phenotypic data that strongly affects comparative analyses (e.g., phylogenetic reconstructions).

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DOI: 10.3897/vz.74.e122822

Authors: Micaela A. Chambi Velasquez, Romina Pavé, María A. Argoitia, Pablo Schierloh, María G. Piccirilli, Valeria C. Colombo, Fernando J. Beltrán, Daniel M. Cisterna, Diego A. Caraballo

Abstract: Abstract Understanding species diversity and delineating their boundaries are crucial for effective management and conservation efforts. In the case of bats, species identification holds particular importance from an epidemiological standpoint. The genus Molossus (Chiroptera: Molossidae) encompasses 15 species distributed across the Neotropics, ranging from the southeastern United States to Argentina. This genus exhibits two contrasting patterns of variation: some species are cryptic, while others are morphologically distinct yet genetically similar. This study explores the diversity of Molossus in Argentina through a molecular phylogenetic approach. We analyzed sequences from three molecular markers (cyt b, COI, and FGB) along with morphology data obtained from a sample of 64 individuals. Uni- and multivariate analyses of external and cranial measurements were conducted, alongside comparisons of external and cranial characteristics among species. Based on molecular and morphological differences, we describe a new species within the Molossus genus. This newly discovered species exhibits a broad distribution spanning the Paraná River basin across three distinct ecoregions. It is noteworthy that this species is pseudo-cryptic with respect to similar-sized species such as M. molossus and M. melini. Additionally, it is important to mention that all species in Argentina have overlapping distribution ranges. In summary, this study provides valuable insights into the diversity and distribution of Molossus bats in Argentina, employing molecular and morphological analyses. The discovery of a new species underscores the ongoing importance of comprehensive research efforts in understanding and conserving bat populations in the Neotropics.

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DOI: 10.3897/vz.74.e122418

Authors: Jason R. Ali, Uwe Fritz

Abstract: Abstract Our focus is the colonization history of the Galápagos’ vertebrate clades: 11 land-bound groups (eight reptiles, three rodents) and 13 taxa of flyers and swimmers (ten winged birds, two pinnipeds, one penguin). Using ‘colonization intervals’ and ‘colonization profiles’, it is clear that the two sets of taxa assembled very differently. The former includes older clades with between one, and potentially eight, predating the emergence of the oldest island (4 Mya). For the origin of some lineages, now-sunken landmasses associated with the Galápagos mantle-plume hotspot must have been involved, but for others it could reflect taxonomic uncertainties. In contrast, the taxa of flyers and swimmers are markedly younger, indicating either higher rates of colonization and extirpation for these sorts of animal, or continued genetic influx from mainland populations, or some combination of both factors. Concerning the first, possible drivers are the environmental stressors associated with the El Niño–La Niña climate system; the recent clades may be vulnerable to extreme events within the oscillation sequence, perhaps on ≥104-year timescales. Therefore, loose temporal thresholds might exist for the archipelago’s vertebrate groups beyond which selection fortifies them from the most challenging of seasonal states. Moreover, in a world of climate uncertainty, the findings appear relevant to conservation initiatives suggesting a focusing on the younger elements within the Galápagos’ biota.

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DOI: 10.3897/vz.74.e115242

Authors: Raquel Alvarado-Larios, Pablo Teta, Pablo Cuello, J. Pablo Jayat, Andrea P. Tarquino-Carbonell, Guillermo D’Elía, Paula Cornejo, Agustina A. Ojeda

Abstract: Abstract The genus Ctenomys Blainville, 1826 includes 68 living species of small to medium-sized (100–1200 g) caviomorph rodents of subterranean habits. During the last decade, this genus has been the subject of numerous taxonomic studies, including the description of new species and the proposal of novel synonyms. Based on phylogenetic analysis of mitochondrial DNA sequences and qualitative and quantitative morphological traits, here we review the species boundaries of the tuco-tucos of the species group of C. mendocinus and describe a new species. The new species is morphologically distinct from other phylogenetically and geographically close species of Ctenomys (e.g., C. fochi, C. mendocinus), showing several differences in their craniodental traits (e.g., proportionally longer nasals and less globose tympanic bullae). The new species occurs in montane grasslands and shrublands of northwestern Mendoza (ca. 2710 m a.s.l.) and in lowlands (ca. 1000 m a.s.l.) of the Monte Desert ecoregion in an area highly impacted by accelerated processes associated with the wine industry.

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DOI: 10.3897/vz.73.e102645

Authors: Juan Fernando Vélez-García, Diego Alejandro Carrión Blanco, Gabriela Moreno Gómez, Stephanie San Martín Cañas

Abstract: Abstract The kinkajou (Potos flavus) is a carnivoran of the suborder Caniformia and the family Procyonidae, inhabiting regions throughout Central and South America. Potos flavus has arboreal preferences and exhibits unique anatomical adaptations that facilitate movement within trees. Its pelvic limbs enable hindfoot reversal, while its thoracic limbs possess remarkable prehensile capabilities. Previous anatomical studies in Potos flavus have presented discrepancies in the description of the intrinsic shoulder and brachial muscles. Therefore, this study aims to provide a comprehensive anatomical description of these muscles in five specimens. The findings are compared with descriptions reported for other caniforms. The application of the Density-Based Spatial Clustering of Application with Noise (DBSCAN) algorithm aids in identifying relationships among caniforms based on the presence or absence of specific muscles. Our analysis reveals several key differences, including the presence of a biceps brachii with two capita (longum and breve), two coracobrachiales muscles (longus and brevis), a tensor fasciae antebrachii with two distinct parts (cranialis and caudalis), and an anconeus medialis. The caput breve of the biceps brachii and coracobrachialis longus muscles are absent in some individuals, with prevalence rates of 10% and 20%, respectively. One specimen exhibited an accessory caput laterale of the m. triceps brachii bilaterally. The comparative analysis suggests that the shoulder and brachial muscles of Potos flavus share more similarities with those of Ailurus fulgens and ursids of the genera Ursus and Tremarctos. These findings suggest the retention of muscles that may have been present in the common ancestor of the infraorder Arctoidea.

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DOI: 10.3897/vz.73.e101487

Authors: Vuong Tan Tu, Neil M. Furey, Tamás Görföl, Alexandre Hassanin, Satoru Arai, Daisuke Koyabu, Bounsavane Douangboubpha, Gábor Csorba

Abstract: This study integrates analyses of mitochondrial DNA sequences and morphological and acoustic data to re-evaluate the taxonomic status of Rhinolophus rex rex, R. r. paradoxolophus and R. schnitzleri throughout their distribution ranges. Based on a dense geographic sampling of specimens hitherto referred to these taxa and contrary to the current taxonomic view, our results indicate that all examined specimens of these taxa are representatives of a single, widely distributed and morphologically variable species, R. rex. The recognition of its geographic populations as different subspecies (R. r. rex and R. r. paradoxolophus) or distinct species (R. schnitzleri) based on morphological and acoustic data should be regarded as invalid. In the light of this revision, we also reassess the conservation status of R. rex against IUCN Red List criteria as Near Threatened.

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DOI: 10.3897/vz.73.e101065

Authors: Pablo Teta, J. Pablo Jayat, Raquel Alvarado-Larios, Agustina A. Ojeda, Pablo Cuello, Guillermo D’Elía

Abstract: The genus Ctenomys of subterranean rodents is one of the most species-rich genera of Mammalia, with 66 living species currently recognized. However, the taxonomy of the genus is dynamic with several new species and new synonymies proposed during the last decade. One of the species groups that have undergone more changes in contents in the last years is the Ctenomys mendocinus species group. Here, based on phylogenetic analysis of mitochondrial DNA sequences and qualitative and quantitative morphological evidence, we conducted an appraisal of the species richness of tuco-tucos of the C. mendocinus species group, describing two new species from west-central Argentina. The new taxa are morphometrically distinctive when compared with other geographically or phylogenetically close species of the genus, showing qualitative differences in their craniodental anatomy. One of the new species is known from the eastern Andean slopes of La Rioja and San Juan provinces, occurring on montane grasslands and shrublands above 3,500 m a.s.l., while the other is endemic of southwestern Mendoza province, occurring on montane grasslands and shrublands between 2,400–2,700 m a.s.l. In addition, we include for the first time the nominal forms C. fochi and C. validus in a phylogenetic analysis of the genus Ctenomys, showing that both correspond to the C. mendocinus species group, being the second a junior synonym of C. mendocinus. Finally, we made some comments about other candidate species within this species group as well as highlight issues that need to be addressed to gain a robust picture of the specific richness of Ctenomys.

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DOI: 10.3897/vz.73.e96656

Authors: Diego H. Verzi, Nahuel A. De Santi, A. Itatí Olivares, Cecilia C. Morgan, Néstor G. Basso, Federico Brook

Abstract: The subterranean rodent Ctenomys is the most polytypic South American mammal genus and one of the most speciose and rapidly diversifying mammal genera in the world. Its systematics is unstable due to the underlying accelerated diversification processes that give rise to evolutionary lineages at different stages of differentiation and to remarkable morphological homogeneity even among long-differentiated species. As a result, species boundaries are often difficult to define. Diversity of this genus in the coastal area of central Argentina has been extensively studied, with two independent lineages currently recognized while a distinct third population had not been previously detected. Through a phylogenetic analysis based on combined morphological and molecular evidence, Bayesian estimates of divergence times, and morphometric and morphological assessments, we recognize this third population as an independently evolving lineage. The new species, Ctenomys pulcer sp. nov., is here described for both the living fauna and the fossil record of the Pampean region of central Argentina. According to phylogenetic results, Ctenomys pulcer sp. nov. belongs to the essentially Patagonian magellanicus clade, and would have diverged from its sister species, Ctenomys bidaui, during the middle Pleistocene (ca. 0.4 Ma). Its current distribution in the fixed and semifixed dunes of the coastal Pampean region is assumed to represent a relict of a wider and continuous distribution of potentially suitable environments during the late Pleistocene. Ctenomys pulcer sp. nov. occurs in a particularly fragile natural system subjected to profound disturbances caused by diverse anthropic actions and therefore measures for the conservation of its habitat will be indispensable.

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DOI: 10.3897/vz.73.e94111

Authors: Willem G. Coetzer

Abstract: The greater cane rat (Thryonomys swinderianus) is an African rodent with a wide Sub-Saharan distribution range. This species is viewed as an important protein source in many African countries. These rodents are also regularly viewed as a pest species who frequently raid croplands in agricultural settings. No phylogenetic work has to date been published on T. swinderianus from southern Africa. This paper therefore reports the first phylogenetic assessment on the species across the South African distribution range. Thirty samples were sourced from local museum collections, with one direct submission by a member of the public who found a rodent carcass identified as T. swinderianus west of its known distribution range in the Eastern Cape Province of South Africa. Two mitochondrial loci previously used in West African studies of this species were used in the current study to asses T. swinderianus population genetic diversity and phylogenetic structure across the South African distribution. A comparison to sequence data from West Africa was also performed. A divergence time estimation was conducted to further investigate the evolutionary history of the South African sub-population. Similar genetic diversity estimates were observed for the South African sub-population when compared to the West African datasets. Specimens from the eastern parts of South Africa showed higher genetic diversity estimates, possibly indicative of an initial colonisation site from eastern Africa. Two distinct phylogenetic clades were identified by Bayesian inference, forming distinct West African and South African groups. The divergence estimates showed similar ages for the T. swinderianus most recent common ancestor (MRCA) as previously reported. The MRCA estimates for the South African group identified a possible middle to late Pleistocene migratory event from eastern African into southern Africa. Further fine scale sampling across the African distribution range is however needed to provide more accurate assessments for future conservation management planning for the different sub-populations, as needed.

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DOI: 10.3897/vz.72.e90958

Authors: Roberto Leonan M. Novaes, Vinícius C. Cláudio, M. Mónica Díaz, Don E. Wilson, Marcelo Weksler, Ricardo Moratelli

Abstract: Myotis is the most speciose genus of mammals in the world and recent taxonomic revisions have revealed an impressive diversity of species in South America. Even so, the phenotypic conservatism of some taxa makes taxonomic delimitation difficult. We perform a taxonomic review of Myotis from Argentina based on qualitative and quantitative morphological characters. Our results confirm the occurrence of 12 species (M. albescens, M. chiloensis, M. dinellii, M. izecksohni, M. keaysi, M. lavali, M. levis, M. nigricans, M. oxyotus, M. riparius, M. ruber, and M. cf. simus) and revealed an additional new species for the Yungas Forest. The new species is small to medium (forearm length ~ 35 mm) and can be distinguished from its congeners by a set of characters that includes forearm length, cranial measurements, discrete craniodental characters, and fur color. This review does not exhaust the need for new systematic studies with Argentinean Myotis, considering the possibility of occurrence of new species and the great morphological variation found for some complex taxa.

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DOI: 10.3897/vz.72.e90840

Authors: Wolfgang Maier, Adrian Tröscher, Irina Ruf

Abstract: Modern phylogenetics place the Soricidae (shrews) into the order Lipotyphla, which belongs to the relatively new superorder clade Laurasiatheria. Their most derived skull feature is the unusual position and shape of the jaw articulation: Whereas in all other mammals the glenoid region of the squamosum is more or less tightly attached to the otic capsule or petrosal, respectively, in the soricids it is attached to the nasal capsule. This new position of the jaw articulation becomes possible by the posterior extension of the nasal capsule and the rostral shift of the glenoid fossa. By the study of dated postnatal ontogenetic stages of Crocidura russula and Sorex araneus, we show that the glenoid part of the squamosal becomes fixed to the nasal capsule by the ossified alae orbitalis and temporalis. The ala orbitalis is displaced laterally by the expanded cupula nasi posterior; this posterior expansion is well documented by the lamina terminalis, which incorporates parts of the palatinum and alisphenoid. Both alae consist largely of ‘Zuwachsknochen’ (‘appositional bone’) and are then named orbitosphenoid and alisphenoid. By the forward move of the pars glenoidea and of the alisphenoid, the foramen lacerum medium (‘fenestra piriformis’) also expands rostrally. Functionally, the forward shift of the jaw joint helps to keep the incisal biting force high. Biomechanically the jaws can be considered as a tweezer, and the rostral position of the jaw joints makes the interorbital pillar and the shell-like walls of the facial skull a lever for the highly specialized incisal dentition.

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DOI: 10.3897/vz.72.e90474

Authors: Zainab Dashti, Hasan Alhaddad, Bader H. Alhajeri

Abstract: Populations of broadly distributed species often exhibit geographic structuring, which is sometimes reflected in phenotype. The monotypic Indian gerbil (Tatera indica) is an example of a widely distributed species, with its range encompassing much of Asia. This study aims to determine if T. indica populations exhibit marked variation in skull morphology—this structure is particularly adaptable and thus could be amenable to show such variation. Furthermore, the potential drivers of skull variation are examined, including the role of climate and geography. To achieve these goals, 21 linear measurements were measured on the skulls of 509 specimens, coming from 111 different localities, across this species wide range. The specimens were then assigned into one of four broad geographic groups (≈ populations) based on their geographic proximity, and the overall and the pairwise differences in the 21 skull measurements among these groups were assessed. Specimens from Pakistan significantly differed from those belonging to the West Iran, East Iran, and India populations, which in turn did not significantly differ from each other. Pairwise bioclimatic and geographic distances between the localities explained a significant, yet small amount of variation in the measurements. Thus, while the Pakistani T. indica population was distinct in skull measurements, both climatic and non-climatic spatial factors seem not to account largely for its distinctiveness (from the other populations).

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DOI: 10.3897/vz.72.e85989

Authors: Holger Preuschoft, Anna Krahl, Ingmar Werneburg

Abstract: Therapsids covered the entire spectrum of terrestrial locomotion from sprawling to parasagittal. Switching between sprawling and more erect locomotion may have been possible in earlier taxa. First, the axial skeleton shows little regionalization and allows lateral undulation, evolving then increasingly towards regionalization enabling dorsoventral swinging. During terrestrial locomotion, every step invokes a ground reaction force and functional loadings which the musculoskeletal system needs to accomodate. First insights into the functional loading regime of the fore- and hindlimb skeleton and the body stem of therapsids presented herein are based on the assessment and preliminary measurements of the historical collection of therapsids exhibited in the Paleontological Collection of Eberhard Karls Universität Tübingen, Germany. The specimens included are the archosaur Hyperodapedon sanjuanensis, the early synapsid Dimetrodon limbatus for comparison, and the therapsids Keratocephalus moloch, Sauroctonus parringtoni, Tetragonias njalilus, and Belesodon magnificus. The vertebral columns and ribs of the mounts were carefully assessed for original fossil material and, when preserved, ribs, sacral, and anterior caudal vertebrae were measured. The body of a tetrapod is exposed to forces as well as bending and torsional moments. To resist these functional stresses, certain musculoskeletal specializations evolved. These include: 1) compression resistant plate-like pectoral and pelvic girdle bones, 2) a vertebral column combined with tendinous and muscular structures to withstand compressive and tensile forces and moments, and 3) ribs and intercostal muscles to resist the transverse forces and torsional moments. The legs are compressive stress-resistant, carry the body weight, and support the body against gravity. Tail reduction leads to restructuring of the musculoskeletal system of the pelvic girdle.

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DOI: 10.3897/vz.72.e82874

Authors: Mathias Wirkner, Katharina Heyder, Irina Ruf

Abstract: The bony labyrinth (inner ear) of mammals reveals systematic as well as morphofunctional information. However, detailed knowledge of bony labyrinth morphology and ontogeny in Pantherinae, that comprise some of the most iconic mammals, is still pending. Hence, we present the first comparative description of the bony labyrinth in all extant species of Panthera and Neofelis some of which are represented by several postnatal stages; particular focus is set on Panthera leo. Our study is based on µCT scans and virtual 3D reconstructions and accompanied by selected morphometric measurements. Even though quite similar in morphology, both genera as well as their species can be distinguished by several features, e.g., shape and relative size of the semicircular canals and presence or absence of an osseous secondary crus commune. In case of the latter, P. pardus shows some intraspecific variation. We also traced the reduction of the fossa subarcuata during ontogeny in P. leo which conforms with previous studies. Negative allometry of the bony labyrinth in relation to skull basal length can be observed during ontogeny as demonstrated by P. leo as well as between different sized species. Although not correlated with the length of the cochlear canal, the number of cochlear turns is higher in captive non-adult P. leo and P. tigris, but lower in adult captive P. pardus. If these intraspecific differences are related to captivity or represent an ontogenetic pattern, needs to be evaluated in future studies based on larger samples.

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DOI: 10.3897/vz.72.e85466

Authors: Kai Ito, Ryo Kodeara, Kazuhiko Koyasu, Quentin Martinez, Daisuke Koyabu

Abstract: The phylogenetic relationships of major groups within the Order Eulipotyphla was once highly disputed, but the advent of molecular studies has greatly improved our understanding about the diversification history of talpids, soricids, erinaceids, and solenodontids. Their resolved phylogenetic relationships now allow us to revisit the turbinal and lamina evolution of this group. The inner structure of the nasal cavity of mammals is highly complicated and the homologies of the turbinals among mammalian species are still largely unsettled. In this regard, investigation on fetal anatomy and ontogenetic changes of the nasal capsule allows us to evaluate the homologies of the turbinals and laminae. We observed various fetuses and adults of talpids and soricids using high-resolution diffusible iodine-based contrast-enhanced computed tomography (diceCT) and reviewed previous reports on erinaceids, solenodontids, and other laurasiatherians. Although the turbinal and lamina morphology was previsouly considered to be similar among eulipotyphlans, we found phylogenetic patterns for talpids and soricids. The nasoturbinal of the common ancestor of talpids and soricids was most likely rostrocaudally elongated. The epiturbinal at the ethmoturbinal II disappeared in soricids independently. Finally, we propose two possible scenarios for the maxilloturbinal development: 1) the maxilloturbinal of talpids and soricids became small independently with a limited number of lamellae as a result of convergent evolution, or 2) the common ancestor of talpids and soricids already had a small and simple maxilloturbinal.

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DOI: 10.3897/vz.72.e86968

Authors: Manfred Drack, Oliver Betz

Abstract: Here, we build on earlier work concerning notions of engineering design and investigate their conceptual connection to evolutionary biology. The basis for this work is an engineering design schema covering the central concepts of function, working principle and construction. Its relevance for evolutionary biology is explored by connecting these concepts to the so-called design space that is used in engineering optimisation. This tool makes it possible to distinguish various optima of performance and to visualise their robustness with respect to disturbances or changes in parameters. The robustness of morphological ‘constructions’ with regard to changes of shape is shown by means of examples from engineering and biology. The characteristics of various ‘landscapes’ in the design space is then related to the concept of evolvability, whereby we explore analogies between systems biology and morphology. A general property of phenotypes from the molecular to the organismal level seems to be that their ‘construction’ facilitates both their robustness and their exploration of the design space while maintaining the performance of the relevant functions at a high level.

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DOI: 10.3897/vz.72.e83544

Authors: Sirpa Nummela, Gabriel Aguirre-Fernández, Kathleen K. Smith, Marcelo R. Sánchez-Villagra

Abstract: We studied the mass growth trajectories of middle ear ossicles and tympanic membrane and oval window area in 19 specimens of postnatal ages 30–180 days of the gray short-tailed opossum Monodelphis domestica. We weighed the skull mass and the mass of the three middle ear ossicles with appropriate balances. Using a binocular microscope provided with a grid, we measured the length of malleus and incus, as well as the longest axis and the one perpendicular to it on both the tympanic membrane and the stapes footplate. The size variation was studied with least squares regression analyses between various measurements. The incus and stapes change little in mass after 40 days of postnatal life, while the malleus does, reaching maximum mass at around 100 PND (postnatal days). This modularity in growth trajectory is in contrast with the shared evolutionary origin of malleus and incus from branchial arch 1. The maturation of the middle – and as indicated by previous work, that of the inner ear – is coupled with the improvement of hearing sensitivity at low and high frequencies after the initial onset of hearing at 29 PND.

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DOI: 10.3897/vz.72.e82709

Authors: M. Judith Babot, Guillermo W. Rougier, Daniel A. García-López, Sara B. Bertelli, Claudia M. Herrera, M. Virginia Deraco, Norberto P. Giannini

Abstract: We present a detailed description of the anatomy of the dentary and lower teeth of a new specimen of Callistoe vincei, a large carnivorous metatherian from the Eocene (?Ypresian) of northwestern Argentina. The recently collected specimen is a young adult represented by a partial right dentary with the canine, p1, roots of p3, and very well-preserved m1 to m4. The description includes a comparison with the holotype specimen, a much older individual, and other closely related large sparassodonts (e.g., Arminiheringia). The analysis of this new material allowed identifying plesiomorphic molar features in Callistoe, such as the presence of a reduced metaconid on the m3 and a tricuspated, basined talonid on m1–m3. We also described the mesowear facets in the lower dentition, showing that the self-sharpening facet typically present in extinct and extant placental and some marsupial carnivorous forms, was absent in Callistoe. The presence of a short-term cutting edge in the trigonid related to the thinness of the enamel layer, and the associated tooth wear susceptibility, were likely compensated by a dental mechanism (overeruption) to maintain occlusal contact among antagonist teeth. This process could explain the marked extrusion of the tooth roots observed in Callistoe as well as in other large closely related members of the group.

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DOI: 10.3897/vz.72.e83324

Authors: Irina Ruf

Abstract: The turbinal skeleton inside the nasal cavity supports the respiratory and olfactory epithelia of the mammalian nose and can provide systematic and morphofunctional information. For the first time, the turbinal skeleton of Pentalagus furnessi (Amami rabbit) from Japan is described based on µCT scans and virtual 3D reconstructions of two specimens. In general, the turbinal skeleton of Pentalagus furnessi resembles the pattern and characters observed in other Leporidae. The maxilloturbinal is highly dendritic, nasoturbinal and crista semicircularis are in close contact and form a common recess, the frontoturbinal recess houses two frontoturbinals and one interturbinal between them, the ethmoturbinal recess houses three ethmoturbinals and one interturbinal between ethmoturbinal I and II. Pentalagus furnessi is derived from the leporid grundplan in having a lamina semicircularis with almost straight posterior margin and ventral lamella and in showing a single-scrolled and relatively short interturbinal between frontoturbinal 1 and 2. These characters can be regarded as autapomorphic for the Amami rabbit. Furthermore, the two specimens have an additional small and short interturbinal between frontoturbinal 2 and ethmoturbinal I that shows some variation. This pattern supports previous observations of intraspecific variation of certain interturbinals in Oryctolagus cuniculus and some Sylvilagus and Lepus species. The comparison of the turbinal skeleton of Pentalagus furnessi and its possible sister taxon (e.g., Pronolagus, Poelagus or Caprolagus) reveals a puzzling pattern which is discussed.

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DOI: 10.3897/vz.72.e78219

Authors: Thomas E. Lee Jr., Nicolás Tinoco, Jorge Brito

Abstract: We name and describe a new species of Andean mouse from the eastern slope of the Andes of central Ecuador (Sangay National Park). This rodent is large-bodied (head-body length 167–184 mm) inhabiting the wet montane forest between 3,400–3,900 m in elevation. A molecular phylogeny based on mitochondrial genes resolved the new species as a member of the “aureus” group, closely related to an undescribed species from north Ecuador. This finding increases the diversity of Thomasomys to 48 species, of which 18 species inhabit Ecuador. In addition, the species described herein is the largest species of the genus described in Ecuador.

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DOI: 10.3897/vz.72.e78234

Authors: Calum J. McKay, Claudia Welbourn-Green, Erik R. Seiffert, Hesham Sallam, Jessica Li, Sophia E. Kakarala, Nigel C. Bennett, Robert J. Asher

Abstract: Macroscelidid afrotherians and canid carnivorans possess four premolar loci, the first of which is not replaced. Previous work suggests that the first premolar in macroscelidids is a retained deciduous tooth, but in Canis it is a successional tooth with no milk precursor. We tested this contrasting interpretation of first premolar homology with data from ontogenetic anatomy and with area predictions from the inhibitory cascade (IC) model. Our results based on anatomy support previous interpretations that the functional first premolar is a retained deciduous tooth (dp1) with no successor in macroscelidids, and a successional tooth (p1) with no precursor in Canis. Hyracoids are among the few placental mammals that show replacement at the first premolar locus and show less deviation than other taxa of actual from predicted areas across the deciduous and molar toothrow. However, predicted vs. actual tooth areas can depart substantially from one another. At least without a better means of representing tooth size, the inhibitory cascade does not help to distinguish the deciduous from successional first premolar. This observation does not rule out the possibility that factors such as a size-shift within the toothrow (e.g., carnivoran carnassials) help to explain deviations from the inhibitory cascade model.

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DOI: 10.3897/vz.72.e78479

Authors: Julia A. Schultz, Rico Schellhorn, Pavel P. Skutschas, Dmitry D. Vitenko, Veniamin V. Kolchanov, Dmitry V. Grigoriev, Ivan T. Kuzmin, Petr N. Kolosov, Alexey V. Lopatin, Alexander O. Averianov, Thomas Martin

Abstract: Abstract A mammalian petrosal from the Lower Cretaceous Teete locality in Yakutia (Russia) shows a prominent and complex system of venous channels in the bony wall of the pars cochlearis surrounding the straight cochlear canal. This complex venous system is distinctive and more strongly developed than in other mammalian petrosals. A bony ridge is present on the ventral side of the cochlear canal endocast, continuing from between fenestra vestibuli and fenestra cochleae in anterior direction. This ridge corresponds to the position of the scala tympani, and is similar to the secondary bony lamina of crown therians, but lacks the sharp laminar edge. The fenestra cochleae is separate from the canal for the aquaeductus cochleae (derived), but the fenestra retains a deep sulcus that resembles the perilymphatic sulcus (plesiomorphic). The fenestra cochleae is oval shaped and deep. The straight cochlear canal with a ridge on the ventral side strongly resembles that of eutriconodontans like Priacodon fruitaensis from the Upper Jurassic of North America. However, thick and extensive venous channels in the pars cochlearis are otherwise known from docodontans. In the Teete petrosal the channels are even more developed, and resemble the pattern recently reported from possible haramiyidan petrosals from the Middle Jurassic of western Siberia (Russia). Both eutriconodontan and haramiyidan dental remains are known from the Teete locality beside that of tritylodontids and docodontans.

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DOI: 10.3897/vz.72.e80508

Authors: John R. Wible

Abstract: Abstract The os paradoxum or dumb-bell-shaped bone is a paired bone occurring in the middle of the specialized bill of the platypus Ornithorhynchus anatinus. It has been variously considered as a neomorph of the platypus, as the homologue of the paired vomer of sauropsids, or as a part of the paired premaxillae. A review of the near 200-year history of this element strongly supports the os paradoxum as a remnant of the medial palatine processes of the premaxillae given its ontogenetic continuity with the premaxillae and association with the vomeronasal organ and cartilage, incisive foramen, and cartilaginous nasal septum. In conjunction with this hypothesis, homologies of the unpaired vomer of extant mammals and the paired vomer of extant sauropsids are also supported. These views are reinforced with observations from CT scans of O. anatinus, the Miocene ornithorhynchid Obdurodon dicksoni, and the extant didelphid marsupial Didelphis marsupialis. At the choanae, Obdurodon has what appears to be a separate parasphenoid bone unknown in extant monotremes.

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DOI: 10.3897/vz.72.e76047

Authors: Timothy D. Smith, Christopher J. Bonar

Abstract: Abstract Nasal anatomy in rodents is well-studied, but most current knowledge is based on small-bodied muroid species. Nasal anatomy and histology of hystricognaths, the largest living rodents, remains poorly understood. Here, we describe the nasal cavity of agoutis (Dasyprocta spp.), the first large-bodied South American rodents to be studied histologically throughout the nasal cavity. Two adult agoutis were studied using microcomputed tomography, and in one of these, half the snout was serially sectioned and stained for microscopic study. Certain features are notable in Dasyprocta. The frontal recess has five turbinals within it, the most in this space compared to other rodents that have been studied. The nasoturbinal is particularly large in dorsoventral and rostrocaudal dimensions and is entirely non-olfactory in function, in apparent contrast to known muroids. Whether this relates solely to body size scaling or perhaps also relates to directing airflow or conditioning inspired air requires further study. In addition, olfactory epithelium appears more restricted to the olfactory and frontal recesses compared to muroids. At the same time, the rostral tips of the olfactory turbinals bear at least some non-olfactory epithelium. The findings of this study support the hypothesis that turbinals are multifunctional structures, indicating investigators should use caution when categorizing turbinals as specialized for one function (e.g., olfaction or respiratory air-conditioning). Caution may be especially appropriate in the case of large-bodied mammals, in which the different scaling characteristics of respiratory and olfactory mucosa result in relative more of the former type as body size increases.

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DOI: 10.3897/vz.71.e70989

Authors: Haithem El-Farhati, Mourad Khaldi, Alexis Ribas, Mohamed Wassim Hizem, Saïd Nouira, Violaine Nicolas

Abstract: Abstract Two species of hedgehogs are known to occur in northern part of Africa: the Algerian hedgehog Atelerix algirus and the Ethiopian hedgehog Paraechinus aethiopicus. Within each species several subspecies were described based on morphometrical data and pelage coloration, but all these subspecies have enigmatic and unclear definitions. We investigated the phylogeographical history and taxonomy of these two species based on mitochondrial DNA data covering the entire geographical distribution of A. algirus and the North African distribution of P. aethiopicus. We also used climatic niche modelling to make inferences about their evolutionary history. Low genetic diversity was recovered in both species. While no phylogeographic pattern was found in P. aethiopicus, two haplogroups were identified within A. algirus. This could be explained by the fact that continuous high or moderate climatic suitability occurred throughout most of the Saharan desert since the LGM (Last Glacial Maximum) for the first species, while during the LGM there were several disconnected areas of high climatic suitability for A. algirus: one in South-West Morocco, one at the coastal Moroccan-Algerian border and one in Tunisia-coastal Libya. Our genetic results confirm that A. algirus recently colonized Spain, Balearic and Canary Islands, and that this colonization was probably mediated by humans. Suitable climatic conditions occurred throughout most of the Southern and Eastern Iberian Peninsula during the last 6,000 years which could have favored the spatial expansion of the Algerian hedgehog after its arrival in Europe. According to our molecular results subspecific recognition within North Africa is unwarranted for both species.

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DOI: 10.3897/vz.71.e73146

Authors: Roberto Leonan M. Novaes, Don E. Wilson, Ricardo Moratelli

Abstract: Abstract The genus Myotis comprises a diverse group of vesper bats with worldwide distribution. Twenty-eight neotropical species are currently recognized. Based on a morphological approach, we describe a new species of Myotis from the Uruguayan Pampas grasslands, an ecoregion under high anthropogenic pressure with a largely unknown bat fauna. Qualitative and quantitative morphological analyses support the recognition of the new species and we present a set of external and cranial diagnostic characters by comparing them with other neotropical Myotis species. The new species reassembles Myotis riparius, but can be distinguished by a set of qualitative and quantitative morphological traits, including its clearly bicolored dorsal fur, tricolored ventral fur, a pelage on the dorsal surface of uropatagium, sagittal crest lower, braincase lower in lateral view and overall smaller size.

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DOI: 10.3897/vz.71.e72811

Authors: Ulrich Zeller, Thomas Göttert

Abstract: This paper deals with reflections that arose after observing prehistoric rock engravings at different locations in Namibia. These observations stimulated comparative considerations with focus on southern Africa and central Europe. Similar to the Aurignacian rock art of European origin, the most common motifs in the Namibian rock engravings are large animals. While in Europe, the species that served as a blueprint for the illustration of Aurignacian rock art have mostly disappeared, the megafauna illustrated on the rock engravings in Namibia can still be found in the immediate vicinity of the rock art. Against this background, we discuss and further develop a comparative regional approach. We reconstruct and evaluate the suitability of African savannas and still-existing megafauna communities as an appropriate reference-frame for natural European grassland systems and extinct associated warm-adapted megafauna (Eemian Interglacial megafauna). Special attention is laid on the unique situation in Africa in the light of a global extinction wave of megafauna following increasing human activity in the Late Quaternary. This leads us to discuss the use of domesticated ungulates as surrogate taxa to fulfill ecosystem functions in Europe as part of concepts termed “rewilding” or “naturalistic grazing”. After critically examining these concepts, we conclude that using domesticated forms as representatives of extinct or locally disappeared species in Europe has its justification to some extent. If, however, the naturally occurring megaherbivore community still exists (Africa), these naturally occurring species should be given priority due to their organismic abilities and limitations adapted to the harsh conditions in their specific environment. Finally, we discuss the application of (transboundary) protected areas as effective instruments to mitigate human-wildlife conflicts. A holistic approach, including nature conservation and preservation of cultural achievements (domesticated forms, grazing systems), appears promising for the effective protection of the natural African savanna ecosystems with their unique fauna elements, as illustrated in rock engravings that inspired us to write this paper.

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DOI: 10.3897/vz.71.e65934

Authors: Nanami Mano, Brody Wood, Lanre Oladipupo, Rebecca Reynolds, Jane Taylor, Emily Durham, James J. Cray, Chris Vinyard, Valerie B. DeLeon, Timothy D. Smith

Abstract: The sphenoid bone articulates with multiple basicranial, facial, and calvarial bones, and in humans its synchondroses are known to contribute to elongation of the skull base and possibly to cranial base angulation. Its early development (embryological, early fetal) has frequently been studied in a comparative context. However, the perinatal events in morphogenesis of the sphenoid have been explored in very few primates. Using a cross-sectional age sample of non-human primates (n=39; 22 platyrrhines; 17 strepsirrhines), we used microcomputed tomographic (µCT) and histological methods to track age changes in the sphenoid bone. In the midline, the sphenoid expands its dimensions at three growth centers, including the sphenooccipital, intrasphenoidal (ISS) and presphenoseptal (PSept) synchondroses. Bilaterally, the alisphenoid is enlarged via appositional bone growth that radiates outward from cartilaginous parts of the alisphenoid during midfetal stages. The alisphenoid remains connected to the basitrabecular process of the basisphenoid via the alibasisphenoidal synchondrosis (ABS). Reactivity to proliferating cell-nuclear antigen is observed in all synchondroses, indicating active growth perinatally. Between mid-fetal and birth ages in Saguinus geoffroyi, all synchondroses decrease in the breadth of proliferating columns of chondrocytes. In most primates, the ABS is greatly diminished by birth, and is likely the earliest to fuse, although at least some cartilage may remain by at least one-month of age. Unlike humans, no non-human primate in our sample exhibits perinatal fusion of ISS. A dichotomy among primates is the orientation of the ABS, which is more rostrally directed in platyrrhines. Based on fetal Saguinus geoffroyi specimens, the ABS was initially oriented within a horizontal plane, and redirects inferiorly during late fetal and perinatal stages. These changes occur in tandem with forward orientation of the orbits in platyrrhines, combined with downward growth of the midface. Thus, we postulate that active growth centers direct the orientation of the midface and orbit before birth.

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DOI: 10.3897/vz.71.e68897

Authors: Emmanuel Matamba, Leigh R. Richards, Michael I. Cherry, Ramugondo V. Rambau

Abstract: Abstract South African small mammals are under-represented in DNA barcoding efforts, particularly from the eastern forested regions of the country. This study reports DNA barcoding of Rhabdomys taxa from previously unsampled parts of the Eastern Cape and KwaZulu-Natal provinces of South Africa. The complete mitochondrial DNA cytochrome oxidase I (COI) gene was sequenced for 101 Rhabdomys sp. individuals from 16 localities from all three main forest groups (coastal, mistbelt, and scarp forests). Molecular data were supplemented with external morphological measurements, including those deemed potential taxonomically diagnostic characters. Findings indicate the area to be inhabited solely by Rhabdomys dilectus chakae. Haplotypes distributed across the three forest groups were separated by shallow sequence divergences ranging from 0.001–0.015 (Kimura 2-parameter model) and displayed very little population genetic structure (FST= 0.071787). Morphological data revealed some regional metric differences in external morphology, but all the head-and-body to tail (HB: tail) ratios match that of R. d. chakae, and consequently, molecular and morphological data are congruent. These data confirm a range extension of R. d. chakae, supporting the utility of COI barcodes in the identification of small mammalian species.

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