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Prozalambdalestes cratodus gen. et sp. nov. is based on a fragmentary dentary from the Lower Cretaceous (Aptian–Albian) Khovoor locality in Gobi Desert, Mongolia. This is the largest eutherian in the Khovoor mammal assemblage. It shows dental specializations of Zalambdalestidae such as procumbent, ever-growing gliriform first lower incisor with restricted enamel and reaching posteriorly p5, and mesiodistally compressed lower molar trigonids. The enamel is restricted to the ventrolabial and ventrolingual sides of the mesial half of the incisor and the enamel band is higher on the labial side. The new taxon retains five lower premolars, with p1 smaller than p2 and p3 smaller than adjacent premolars, and the Meckelian groove. It also differs from other zalambdalestids by position of mental foramina (under p3 and p5), p1–3 obliquely set in dentary, and lower molar talonids wider than trigonids. Phylogenetic analysis places Prozalambdalestes gen. nov. in a polytomy with Albian Zhangolestes, Turonian Kulbeckia, and the clade of Campanian zalambdalestids from Mongolia and Kazakhstan. CT data in Zalambdalestes and comparison with Prozalambdalestes gen. nov. show that the four lower premolars in Zalambdalestes are p2, p3 (variable present), p4, and p5. Consequently, the three lower premolars of Barunlestes and Zofialestes are p2, p4, and p5. The other diagnostic characters of Zalambdalestidae are reviewed. [ABSTRACT FROM AUTHOR]

Tashtykia primaeva gen. et sp. nov. and Tagaria antiqua gen. et sp. nov. (Multituberculata incertae sedis) are described based on isolated teeth from the Middle Jurassic (Bathonian) Itat Formation from the Berezovsk coal mine in Krasnoyarsk Territory, Western Siberia, Russia. Tashtykia primaeva gen. et sp. nov. is characterized by a P5 with three rows of cusps (cusp formula 2B:4M:6L) and a high sectorial p4 with two triangular lobes, five serrations associated with labial and lingual ridges, and a unique distal cusp. Tagaria antiqua gen. et sp. nov. differs from all other multituberculates by a very long P5 with flat crown and many cusps arranged in three rows (4B:6M:7L). Morphologically the teeth of Kermackodon and Megaconus are transitional between Euharamiyida and Middle Jurassic Multituberculata. Kermackodon shares several characteristics with Euharamiyida, such as pointed cusps on the molars connected by longitudinal ridges, a distolabial cusp on the M2 that is higher than the other cusps, and a single large sectorial premolar (p4) with a distal basin. The euharamiyidan characters of Megaconus are an ultimate upper premolar with a shorter lingual side, a p4 with a distal basin, and one cusp on the molars being larger than the other cusps. In addition, Megaconus shares an ultimate upper premolar with three rows of cusps, horizontal wear on the molars, and pyramidal cusps on the molars separated by transverse grooves with multituberculates. The multituberculate characters of Kermackodon include horizontal rather than basined wear on the surface of the molars and serrations on the p4. [ABSTRACT FROM AUTHOR]

Arnebolagus leporinus Lopatin and Averianov, 2008, known previously from a single tooth (P3) from the early Eocene Bumban Member of Naran Bulak Formation at Tsagan-Khushu locality in Mongolia, is redescribed based on additional specimens from the type locality. Phylogenetic relationships of Eocene stem lagomorphs from Asia and North America are reconstructed for the first time based on a parsimony analysis of 54 morphological characters and 32 taxa. Two new node-based clades are proposed, stemming from the most-recent common ancestor of Lepus Linnaeus, 1758 and Dawsonolagus Li, Meng, and Wang, 2007 (Eulagomorpha new clade, 'lagomorphs of the modern aspect') and from the most-recent common ancestor of Lepus and Gobiolagus Burke, 1941 (Epilagomorpha new clade). Arnebolagus Lopatin and Averianov, 2008 is geologically oldest and the most plesiomorphic eulagomorph, similar to Dawsonolagus from the early Eocene Arshanto Formation of China in its weakly pronounced, unilateral hypsodonty of the upper cheek teeth and its brachyodont lower cheek teeth with separate roots. Arnebolagus is more plesiomorphic than Dawsonolagus in having two roots of P4. Arnebolagus is the oldest known eulagomorph, the only taxon known from the earliest Eocene Bumbanian Asiatic Land Mammal Age (ALMA). The other Asiatic early Eocene eulagomorphs (Dawsonolagus, Aktashmys Averianov, 1994, and Romanolagus Shevyreva, 1995) come from the Arshantan ALMA. [ABSTRACT FROM AUTHOR]

Currently, there are two sauropod taxa known from the Upper Cretaceous (Maastrichtian) Nemegt Formation of Gobi Desert, Mongolia: Nemegtosaurus from the Nemegt locality and Opisthocoelicaudia from the Altan Uul IV locality. Both taxa are represented by not overlapping elements (skull and partial postcranial skeleton respectively), which arises question on their possible synonymy. Five articulated sauropod dorsal vertebrae (PIN 3837/P821, dorsals 6-10) were found in 1949 by the Mongolian Expedition of the Academy of Sciences of the USSR at the Nemegt locality. This specimen is similar to Opisthocoelicaudia in having a strong ventral ridge on dorsal centra, a low neural arch which is anteroposteriorly narrowest at the junction with the centrum and widens dorsally, and lack of hyposphene-hypantrum articulations. PIN 3837/P821 differs from Opisthocoelicaudia by having the less dorsoventrally flattened dorsal centra, a shallow ventral concavity of dorsal centra in lateral view, a vertical posterior centrodiapophyseal lamina (pcdl) in dorsals 8 and 9, a postzygodiapophyseal lamina (podl) that roofs the centrodiapophyseal fossa (pocdf), and strongly developed accessory laminae within the parapophyseal centrodiapophyseal fossa (pacdf). The sauropod femora from Nemegt Formation differ from the femur of Opisthocoelicaudia by the medial condyle extending more distally compared with the lateral condyle. Most likely these femora and PIN 3837/P821 belong to Nemegtosaurus, which would make this taxon distinct from Opisthocoelicaudia by discussed characters of dorsal vertebrae and femur. [ABSTRACT FROM AUTHOR]

The present work describes for a first time a fused fracture of the metacarpals of the medium-sized felid, Lynx issiodorensis, the putative ancestor of all Eurasian extant lynx species. The studied remains, four metacarpals from the same individual, were unearthed from the Early Pleistocene of the Taurida cave (Crimean Peninsula) and studied through computed tomography. These remains exhibit pronounced signs of osteopathology, namely, fracture with displacement of the fifth metacarpal bone fused with the formation of callus and deformation of the bone itself. The pathological process is spread to adjacent metacarpal bones. The likely cause of the injury could be an unsuccessful hunt or an awkward landing from a height. After the injury and in the process of healing the fracture, the studied individual survived with clearly limited hunting abilities. [ABSTRACT FROM AUTHOR]

This paper describes in detail a compact (2U format) telescope operating in the extreme ultraviolet range for studying the solar corona at a wavelength of 17.14 nm. The telescope objective has been built according to the Ritchey-Chrétien scheme with the following parameters: effective focal length of 381.3 mm, field of view of 2×2 ∘ , and angular resolution of 11 in. Reflective multilayer Al/Be coatings were used, having 55% reflectance and a 0.4 nm spectral bandwidth. The wavefront rms error is 30 nm. An interferometric technique for controlling the shapes of the substrates and for adjusting the optical system and detector of the telescope assembly is described in detail.