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The phylogenetic relationships of the Paleocene crocodylian Akanthosuchus langstoni are assessed using published data matrices and morphological data from the holotype and referred specimens. Cladistic analyses indicate that Akanthosuchus is unequivocally nested within Alligatoroidea. Weak support from a majority rule consensus tree indicates that Akanthosuchus may be more closely allied with alligatorines than with caimanines, but in the strict consensus tree these relationships remain ambiguous. There is no evidence from phylogenetic analyses to support the hypothesis that Akanthosuchus represents the postcrania of the Paleocene crocodylians Navajosuchus or Ceratosuchus. Growth marks observed in histological sections of osteoderms of the holotype of Akanthosuchus langstoni indicate that it was at least eight years old at the time of death. Although the individual may not have been fully mature at the time of death, lineage dwarfism cannot be ruled out as a possible reason for its relatively small size.
A taxonomic revision is made of the Palaearctic species of Myrmica belonging to the schencki-group. Three new species are described: M. siciliana (all castes) from Sicily, M. onoyamai (all castes) from Japan and M. inucta (workers only) from northwest Kazakhstan; also first descriptions are made of the sexual castes for two species: M. caucasicola (queen) and M. koreana (queens and males). Keys to the identification of both workers and males of all species, and maps of their distributions are provided. The distribution of the various species is discussed and it is suggested that the origins of extant Palaearctic schencki-group species is linked to the development of the Steppe Zone during the last 10 million years.
The morphology of the single preserved molar of the holotype of the Australian Early Cretaceous (Aptian) mammal Teinolophos trusleri shows that it is a monotreme and probably a steropodontid, rather than a 'eupantothere' as originally proposed. The structure of the rear of the jaw of T. trusleri supports the molecular evidence that previously formed the sole basis for recognising the Steropodontidae as a distinct family.
A new species of small Kerivoula is described from peninsular Malaysia. It is similar in size and form to Kerivoula hardwickii Miller 1898 or K. intermedia Hill and Francis 1984, but is distinguished by its distinctive colouration — dorsal fur has extensive black bases with shiny golden tips, ventral fur has dark grey bases with whitish-buff tips — as well as several characters of dentition and skull shape. Sequence analysis of the first 648 base pairs of cytochrome oxidase I gene (DNA barcode) indicates a divergence of at least 11% from all other species of Kerivoula, a difference comparable to that between other species of Kerivoula.
Subgenus Caverneleodes of the genus Eleodes is diagnosed and revised. Six new species from the United States: California (E. microps); Utah and Northern Arizona (E. wynnei), Central Arizona (E. wheeleri), Southern New Mexico (E. guadalupensis), and Mexico (E. thomasi and E. grutus) are described. The biogeography of the subgenus is discussed. Diagnoses and a key are provided to known species of Caverneleodes. Relationships with other Eleodes are discussed. Cave associated Amphidorini are surveyed.
The Late Cretaceous South American sauropods Neuquensaurus australis and Saltasaurus loricatus are represented by well−preserved and abundant material that has been integral to our understanding of titanosaur anatomy for decades. Although the hypodigms for these species span most of the skeleton, holotypic materials are limited to a few bones that do not overlap between the two taxa. In this contribution, we augment the holotype of Neuquensaurus australis with a partial sacrum that was preserved in articulation with one of the caudal vertebrae from its original description, but not recognised as such at the time. We document this field association via the presence of a broken piece of matrix on the sixth sacral vertebral centrum that has a snap−fit to matrix on the rim of the anterior condyle of the holotypic biconvex vertebra. Based on comparisons with a more complete sacrum and ilium of a referred specimen of Neuquensaurus australis, we interpret this biconvex vertebra to be the seventh sacral vertebra. This raises the possibility that the biconvex “first caudal” vertebra of some other titanosaurs may be part of the sacrum as well. Augmentation of the Neuquensaurus australis holotype to include a sacrum makes it directly comparable to the holotype of Saltasaurus loricatus. Morphological differences in the number, shape, and proportion of sacral vertebrae allow discrimination between Neuquensaurus and Saltasaurus, confirming their generic separation. The El Brete quarry, which preserves the holotypic sacrum and abundant referred specimens of Saltasaurus loricatus, also preserves a sacrum consisting of seven vertebrae that bears autapomorphies of Neuquensaurus australis, indicating that these two saltasaurines coexisted.
A rich conodont fauna from two Neotethyan sections, Pizzo Mondello (western Sicily, Italy) and Pignola 2 sections (southern Apennines, Italy) includes conodonts described herein as a new species. Metapolygnathus praecommunisti sp. nov. is transitional between Paragondolella noah and Metapolygnathus communisti. The genus Metapolygnathus (including M. praecommunisti) is now characterised by posterior prolongation of the keel termination, associated with a centrally located pit and with a weak ornamentation confined to the anterior part of the platform margins. The establishment of M. praecommunisti addresses the problems related to the origin and the peculiar, probably facies−controlled, distribution of its descendant species M. communisti. Since M. praecommunisti occurs in the entire Tethys and in North America, we propose the species as a good guide fossil for global correlations, characterised by a short temporal range limited to the uppermost Tuvalian (upper Carnian). The stratigraphic occurrence of the genus Metapolygnathus is restricted to the Tuvalian–Lacian (upper Carnian–lower Norian), excluding its presence in the Julian substage (lower Carnian).
The holotype of the brachyopoid temnospondyl Hadrokkosaurus bradyi, represented by a right lower jaw ramus, is re−examined based upon new data and revision of various morphological features. Additional fragmentary jaw material referred to this species is briefly described. Prominent features are a large postsymphyseal foramen that is anteriorly open, and prearticular and surangular buttresses for support of the articular. Brachyopoid characters include a long and robust postglenoid area formed by surangular and prearticular, anterior and posterior keels on at least some marginal dentary teeth, and subtriangular outline of the adductor fossa in dorsal view. Five features of the holotype ramus, long thought to be at odds with its brachyopoid or temnospondyl nature, are critically re−evaluated. A phylogenetic analysis of lower jaw characters in temnospondyls retrieves most of the clades found in more comprehensive data sets, but the statistical node support is low. Brachyopoids are monophyletic, with Hadrokkosaurus emerging as their most basal taxon.
A new species of Hipposideros is described from South-East Sulawesi, Indonesia. Morphologically, it shows close affinities to Hipposideros papua but is substantially smaller. It is currently only known from Rawa Aopa Watumohai National Park, an area of semi-disturbed lowland rainforest, where it was the most common species of hipposiderid recorded. In this paper, data on its morphometrics and echolocation are included, along with a brief discussion of its ecology and reproductive biology.
Multituberculates were dominant mammals in the Late Cretaceous communities of Central Asia (present-day Mongolia), but very rare in the Late Cretaceous faunal assemblages from western Asia (Uzbekistan), where ungulate-like mammals dominated (Nessov et al. 1998). So far only one Late Cretaceous multituberculate taxon Uzbekbaatar kizylkumensis Kielan-Jaworowska & Nessov, 1992 was known from Uzbekistan. Here I describe the second Late Cretaceous multituberculate from the same area, Uzbekbaatar wardi sp. n., based upon an isolated p4 from the ?Santonian Aitym Formation at Dzharakuduk, Central Kyzylkum Desert, Uzbekistan. It differs from the Coniacian Uzbekbaatar kizylkumensis by somewhat derived morphology (larger size, greater number of p4 ridges and serrations).
Chitracephalus dumonii was named based on some of the most complete turtle remains from the Lower Cretaceous of Europe, and yet the taxon has barely been mentioned since. Indeed, new specimens were erroneously attributed to a new taxon, “Salasemys pulcherrima”. The synonymy is recognized here, and this extends the geographical range of this turtle and provides examples of individuals at different stages of ontogenetic development. The peculiar structure of its shell, and its ontogenetic development, are unique to this taxon. The systematic position of C. dumonii was previously unclear, usually being referred to Testudinata incertae sedis. Here, it is placed in a cladistic analysis, which shows that C. dumonii, and the recently described Hoyasemys jimenezi form part of a Lower Cretaceous European clade of Cryptodira that includes “macrobaenid”, “sinemydid”, and panchelonioidean turtles.
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