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Extinct Animals News
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A tiny new marsupial lion (Marsupialia, Thylacoleonidae) from the early Miocene of Australia
Microleo attenboroughi Gillespie, Archer & Hand, 2016  *This image is copyright of its original author Reconstruction credits: Peter Schouten Abstract: "Microleo attenboroughi, a new genus and species of diminutive marsupial lion (Marsupialia: Thylacoleonidae), is described from early Miocene freshwater limestones in the Riversleigh World Heritage Area, northwestern Queensland, Australia. A broken palate that retains incomplete cheektooth rows demonstrates that this new, very small marsupial lion possessed the elongate, trenchant P3 and predominantly subtriangular upper molars characteristic of thylacoleonids, while other features of the premolar support its placement in a new genus. Phylogenetic analysis suggests that Microleo attenboroughi is the sister taxon to all other thylacoleonids, and that Thylacoleonidae may lie outside Vombatomorphia as the sister taxon of all other wombat-like marsupials including koalas. However, given limited data about the cranial morphology of M. attenboroughi, Thylacoleonidae is concluded here, conservatively, to be part of the vombatomorphian clade. This new thylacoleonid brings to three the number of marsupial lion species that have been recovered from early Miocene deposits at Riversleigh and indicates a level of diversity previously not seen for this group. It is likely that the different size and morphology of the three sympatric taxa reflects niche partitioning and hence reduced competition. Thylacoleonids may have been the dominant arboreal predators of Cenozoic Australia."
Arktocara yakataga, a new fossil odontocete (Mammalia, Cetacea) from the Oligocene of Alaska and the antiquity of Platanistoidea
Arktocara yakataga Boersma & Pyenson, 2016  *This image is copyright of its original author Reconstruction credits: Alexandra Boersma Abstract: "The diversification of crown cetacean lineages (i.e., crown Odontoceti and crown Mysticeti) occurred throughout the Oligocene, but it remains an ongoing challenge to resolve the phylogenetic pattern of their origins, especially with respect to stem lineages. One extant monotypic lineage, Platanista gangetica (the Ganges and Indus river dolphin), is the sole surviving member of the broader group Platanistoidea, with many fossil relatives that range from Oligocene to Miocene in age. Curiously, the highly threatened Platanista is restricted today to freshwater river systems of South Asia, yet nearly all fossil platanistoids are known globally from marine rocks, suggesting a marine ancestry for this group. In recent years, studies on the phylogenetic relationships in Platanistoidea have reached a general consensus about the membership of different sub-clades and putative extinct groups, although the position of some platanistoid groups (e.g., Waipatiidae) has been contested. Here we describe a new genus and species of fossil platanistoid, Arktocara yakataga, gen. et sp. nov. from the Oligocene of Alaska, USA. The type and only known specimen was collected from the marine Poul Creek Formation, a unit known to include Oligocene strata, exposed in the Yakutat City and Borough of Southeast Alaska. In our phylogenetic analysis of stem and node-based Platanistoidea, Arktocara falls within the node-based sub-clade Allodelphinidae as the sister taxon to Allodelphis pratti. With a geochronologic age between ∼29–24 million years old, Arktocara is among the oldest crown Odontoceti, reinforcing the long-standing view that the diversification for crown lineages must have occurred no later than the early Oligocene." Other articles related: New species of extinct river dolphin discovered in Smithsonian collection
The Middle Pleistocene vertebrate fauna from Khok Sung (Nakhon Ratchasima, Thailand): biochronological and paleobiogeographical implications Suraprasit et al., 2016
 *This image is copyright of its original author Figure 14. Cranial remains of Axis axis from Khok Sung: A–B DMR-KS-05-04-18-50, a cranium with nearly complete antlers in dorsal (A) and ventral (B) views C–D DMR-KS-05-03-00-30, a cranium in lateral © amd ventral (D) views E DMR-KS-05-03-18-X9, a cranium in anterior view F–G DMR-KS-05-03-27-1 a cranium in dorsal (F) and ventral (G) views H DMR-KS-05-03-31-30, a right antler in anterior view; (I) DMR-KS-05-03-22-4, a right antler in lateral view J DMR-KS-05-03-18-21, a left antler fragment in lateral view K DMR-05-03-22-2, a left antler fragment in lateral view L DMR-KS-05-03-19-81, a left antler fragment in medial view. Abstract: "The fluviatile terrace deposits of Khok Sung, Nakhon Ratchasima province, have yielded more than one thousand fossils, making this the richest Pleistocene vertebrate fauna of Thailand. The excellent preservation of the specimens allows precise characterization of the faunal composition. The mammalian fauna consists of fifteen species in thirteen genera, including a primate, a canid, a hyaenid, proboscideans, rhinoceroses, a suid, cervids, and bovids. Most species correspond to living taxa but globally (Stegodon cf. orientalis) and locally (Crocuta crocuta ultima, Rhinoceros unicornis, Sus barbatus, and Axis axis) extinct taxa were also present. The identification of Axis axis in Khok Sung, a chital currently restricted to the Indian Subcontinent, represents the first record of the species in Southeast Asia. Three reptilian taxa: Crocodylus cf. siamensis, Python sp., and Varanus sp., are also identified. Faunal correlations with other Southeast Asian sites suggest a late Middle to early Late Pleistocene age for the Khok Sung assemblage. However, the Khok Sung mammalian fauna is most similar to that of Thum Wiman Nakin, dated to older than 169 ka. The Khok Sung large mammal assemblage mostly comprises mainland Southeast Asian taxa that migrated to Java during the latest Middle Pleistocene, supporting the hypothesis that Thailand was a biogeographic pathway for the Sino-Malayan migration event from South China to Java."
Placoderm Assemblage from the Tetrapod-Bearing Locality of Strud (Belgium, Upper Famennian) Provides Evidence for a Fish Nursery Olive, Clément, Daeschler & Dupret, 2016
 *This image is copyright of its original author Fig 2. Reconstruction of the immature placoderms and diagrammatic model of the Strud nursery. Immature placoderms (from top to bottom) Turrisaspis strudensis (left lateral view), Grossilepis rikiki (dorsal view), Phyllolepis undulata (dorsal view). Diagrammatic model of the Strud nursery displaying the habitat partitioning: on the left, shallow waters of the nursery with immature placoderms inside and Rhacophyton plant on the bank; on the right, deeper area with the placoderm adults. Scale bars equal 2 cm. Animal and environmental reconstructions by J. Jacquot Haméon (MNHN, Paris). Abstract: "The placoderm fauna of the upper Famennian tetrapod-bearing locality of Strud, Belgium, includes the antiarch Grossilepis rikiki, the arthrodire groenlandaspidid Turrisaspis strudensis and the phyllolepidid Phyllolepis undulata. Based on morphological and morphometric evidence, the placoderm specimens from Strud are predominantly recognised as immature specimens and this locality as representing a placoderm nursery. The Strud depositional environment corresponds to a channel in an alluvial plain, and the presence of a nursery in such environment could have provided nutrients and protection to the placoderm offspring. This represents one of the earliest pieces of evidence for this sort of habitat partitioning in vertebrate history, with adults living more distantly from the nursery and using the nursery only to spawn or give live birth." Other articles related: Finding Nemo, Paleozoic Style
Fossil snake preserving three trophic levels and evidence for an ontogenetic dietary shift Smith & Scanferla, 2016
 *This image is copyright of its original author Fig. 1 SMF ME 11332a, comprising a juvenile specimen of the snake Palaeopython fischeri and its prey. Arrow points to the tip of the snout of the lizard inside the snake  *This image is copyright of its original author Fig. 2 a Interpretive drawing of SMF ME 11332a overlaid on a photograph. The lizard, Geiseltaliellus maarius (orange), is preserved in the stomach of the snake (white). The lizard was swallowed headfirst, and the tail does not appear to have been shed during the encounter with the snake. The position of the insect in the abdominal cavity of the lizard is indicated in outline (blue). All Rights Reserved. b, c CT reconstruction of the snake skull in right ventrolateral and left dorsolateral views, respectively. d CT reconstruction of mid-trunk vertebrae of the snake in dorsal view. e Photograph of mid-trunk vertebrae of the snake in ventral view. f Part of the string of vertebrae, to the same scale, comprising the holotype of Palaeopython fischeri (SMF ME 929), four trunk vertebrae in dorsal (left) and ventral (right) views (after Schaal 2004), showing the significant size difference between the holotype and the new specimen. Abbreviations: bo basioccipital, bs-ps basiparasphenoid, ec ectopterygoid, fr frontal, lm left mandible, mx maxilla, n nasal, p parietal, pfr prefrontal, pl palatine, pmx premaxilla, pt pterygoid, q quadrate, rm right mandible, so supraoccipital, st supratemporal. Published with kind permission of ©Krister T. Smith 2016 Abstract: "We report a fossil snake from the middle Eocene (48 Ma) Messel Pit, in whose stomach is a lizard, in whose stomach is an insect. This is the second known vertebrate fossil containing direct evidence of three trophic levels. The snake is identified as a juvenile of Palaeopython fischeri on the basis of new characters of the skull; the lizard is identified as Geiseltaliellus maarius, a stem-basilisk; and the insect, despite preserved structural colouration, could not be identified more precisely. G. maarius is thought to have been an arboreal species, but like its extant relatives may have foraged occasionally on the ground. Another, larger specimen of G. maarius preserves plant remains in the digestive tract, suggesting that omnivory in this species may have been common in larger individuals, as in extant Basiliscus and Polychrus. A general picture of the trophic ecology of P. fischeri is not yet possible, although the presence of a lizard in the stomach of a juvenile individual suggests that this snake could have undergone a dietary shift, as in many extant boines." Other articles related: Amazing ‘Nesting Doll’ Fossil Reveals Bug in Lizard in Snake
Description of a new long-snouted beaked whale from the Late Miocene of Denmark: evolution of suction feeding and sexual dimorphism in the Ziphiidae (Cetacea: Odontoceti)
Dagonodum mojnum Ramassamy, 2016  *This image is copyright of its original author Abstract: "A new genus and species of Ziphiidae, Dagonodum mojnum gen. nov., sp. nov., from the upper Miocene Gram Formation (c. 9.9–7.2 Ma) represents the first occurrence of the family in Denmark. This long-snouted ziphiid is characterized by two pairs of mandibular tusks, the Eustachian outlet that approximately levels with the dorsalmost margin of the posterior portion of the involucrum, and the left trapezoid nasal with a posteromedial projection into the frontal. A phylogenetic analysis including 25 species and 69 characters was conducted. Dagonodum mojnum is placed in a basal ziphiid clade as the sister taxon of Messapicetus. The specimen is probably a male, because it has enlarged tusks. Alternatively, females could also be involved in fights and develop erupted tusks as in the extant Berardius. Although less well supported, this interpretation proposes that aggressive interactions were not restricted to males in stem-ziphiids. With a thickened thyrohyal and the presence of a precoronoid crest, D. mojnum was able to use suction feeding, but was less specialized to it compared to extant ziphiids. The elongated neck of D. mojnum less optimized to perform deep dives, and the shallow depth at which the Gram Formation was deposited corroborates the hypothesis that at least part of the stem-ziphiids were not regular deep divers." Other articles related: Mød Mojn-hvalen fra Gram
A roller-like bird (Coracii) from the Early Eocene of Denmark
Septencoracias morsensis Bourdon, Kristoffersen & Bonde, 2016  *This image is copyright of its original author Figure 3: Life reconstruction of Septencoracias morsensis gen. et sp. nov. Abstract: "The fossil record of crown group birds (Neornithes) prior to the Cretaceous-Paleogene boundary is scarce and fragmentary. Early Cenozoic bird fossils are more abundant, but are typically disarticulated and/or flattened. Here we report the oldest roller (Coracii), Septencoracias morsensis gen. et sp. nov. (Primobucconidae), based on a new specimen from the Early Eocene (about 54 million years ago) Fur Formation of Denmark. The new fossil is a nearly complete, three-dimensionally preserved and articulated skeleton. It lies at the lower end of the size range for extant rollers. Salient diagnostic features of Septencoracias relative to other Coracii include the proportionally larger skull and the small, ovoid and dorsally positioned narial openings. Our discovery adds to the evidence that the Coracii had a widespread northern hemisphere distribution in the Eocene. Septencoracias is the oldest substantial record of the Picocoraciae and provides a reliable calibration point for molecular phylogenetic studies."
A new large-bodied species of Bothriolepis (Antiarchi) from the Upper Devonian of Ellesmere Island, Nunavut, Canada
Bothriolepis rex Downs, Daeschler, Garcia & Shubin, 2016  *This image is copyright of its original author Fossil bones from the skull of Bothriolepis rex and a line drawing of the head viewed from above. The large, thick bones create an armor with a single opening for the eyes. The mouth is on the lower surface of the skull, indicating a bottom-feeding lifestyle. Credits: Valentina Garcia, drawing by Jason Downs. Abstract: "New material from the Upper Devonian (Frasnian) Nordstrand Point Formation of Ellesmere Island, Nunavut, Canada, represents the largest known species of antiarch and the first described from the Nordstrand Point Formation. Bothriolepis rex, sp. nov., is additionally remarkable for the thickness and compactness of its dermal skeletal plates. The new species is diagnosed by a preorbital recess with a horizontal rostral margin; the presence of a wide unornamented border surrounding the infraorbital sensory line; central sensory lines that meet the margin of the nuchal close to the lateral corners; a supraotic thickening that does not extend caudal to a transverse crista of the nuchal; and a tall lateral lamina of the anterior dorsolateral. The thick and compact armor of Bothriolepis rex, sp. nov., recalls that of the co-occurring Perscheia pulla and gives occasion to a physical and ecological review of dermal skeletal mass and density in large-bodied, bottom-dwelling organisms in nonmarine ecosystems during the Late Devonian." Other articles related: A New ‘King’ — New, Gigantic, Ancient Armored Fish Discovered 
Biggest-Ever Flying Bird Soared With 20-Foot Wingspan
 *This image is copyright of its original author The world’s largest-ever flying bird has just been identified, according to scientists who say the bird’s wingspan was about 24 feet long, which is around the same length as a dance floor suitable for 160 people The long-extinct bird, named Pelagornis sandersi in honor of retired Charleston Museum curator Albert Sanders, was appropriately unearthed at what is now the site of the Charleston International Airport. This literal big bird, described in the latest issue of the Proceedings of the National Academy of Sciences, took off from the site in Charleston, S.C., 25 to 28 million years ago. Continue reading... http://www.seeker.com/biggest-ever-flyin...69185.html
A burrowing frog from the late Paleocene of Mongolia uncovers a deep history of spadefoot toads (Pelobatoidea) in East Asia
Prospea holoserisca Chen, Bever, Yi & Norell, 2016  *This image is copyright of its original author Figure 1: IGM 2/001, holotype of Prospea holoserisca. (a) The original specimen in rock matrix and jackets before preparation, preserved in part and counterpart; (b) the specimen in ventral and dorsal view after the preparation (Supplementary Experimental Procedures: fossil preparetion). Abstract: "Fossils are indispensible in understanding the evolutionary origins of the modern fauna. Crown-group spadefoot toads (Anura: Pelobatoidea) are the best-known fossorial frog clade to inhabit arid environments, with species utilizing a characteristic bony spade on their foot for burrowing. Endemic to the Northern Hemisphere, they are distributed across the Holarctic except East Asia. Here we report a rare fossil of a crown-group spadefoot toad from the late Paleocene of Mongolia. The phylogenetic analysis using both morphological and molecular information recovered this Asian fossil inside the modern North American pelobatoid clade Scaphiopodidae. The presence of a spade and the phylogenetic position of the new fossil frog strongly support its burrowing behavior. The late Paleocene age and other information suggestive of a mild climate cast doubt on the conventional assertion that burrowing evolved as an adaptation to aridity in spadefoot toads. Temporally and geographically, the new fossil provides the earliest record of Scaphiopodidae worldwide, and the only member of the group in Asia. Quantitative biogeographic analysis suggests that Scaphiopodidae, despite originating in North America, dispersed into East Asia via Beringia in the Early Cenozoic. The absence of spadefoot toads in East Asia today is a result of extinction."
Tiny individuals attached to a new Silurian arthropod suggest a unique mode of brood care
Aquilonifer spinosus Briggs, Siveter, Siveter, Sutton & Legg, 2016  *This image is copyright of its original author Significance: "The paper reports a remarkable arthropod from the Silurian Herefordshire Lagerstätte of England. The fossil reveals a unique association in an early Paleozoic arthropod involving tethering of 10 tiny individuals each by a single thread to the tergites so that their appearance is reminiscent of kites. The evidence suggests that these are juveniles and that the specimen records a unique brooding strategy. This is part of a diversity of complex brooding behaviors in early arthropods heralding the variety that occurs today. The possibility that the small individuals represent a different arthropod, possibly parasitic, which colonized the larger individual, seems less likely." Abstract: "The ∼430-My-old Herefordshire, United Kingdom, Lagerstätte has yielded a diversity of remarkably preserved invertebrates, many of which provide fundamental insights into the evolutionary history and ecology of particular taxa. Here we report a new arthropod with 10 tiny arthropods tethered to its tergites by long individual threads. The head of the host, which is covered by a shield that projects anteriorly, bears a long stout uniramous antenna and a chelate limb followed by two biramous appendages. The trunk comprises 11 segments, all bearing limbs and covered by tergites with long slender lateral spines. A short telson bears long parallel cerci. Our phylogenetic analysis resolves the new arthropod as a stem-group mandibulate. The evidence suggests that the tethered individuals are juveniles and the association represents a complex brooding behavior. Alternative possibilities—that the tethered individuals represent a different epizoic or parasitic arthropod—appear less likely."
Palaeoamyda messeliana nov. comb. (Testudines, Pan-Trionychidae) from the Eocene Messel Pit and Geiseltal localities, Germany, taxonomic and phylogenetic insights Cadena, 2016
 *This image is copyright of its original author Figure 2: Palaeoamyda messeliana SMF ME 1211. (A) articulated skeleton in dorsolateral view. (B) outline of the carapace and lateral plastral elements in dorsolateral view. © close-up of the right hindlimb. (D) close-up of the tail. (E) close-up of the right forelimb. Abbreviations: co, costal bone; hyo, hyoplastron; hyp, hypoplastron; ne, neural bone; nu, nuchal bone. Background: "Abundant pan-trionychid (soft-shell) turtles specimens have been found in Eocene sequences of central Europe, particularly from two localities in Germany, the Messel Pit (a UNESCO World Natural Heritage Site) and Geiseltal, traditionally attributed to Trionyx messelianus or Rafetoides austriacus. Over the last two decades new specimens of this taxon from these two localities have been discovered and fully prepared. However, they have remained unstudied, as well as their phylogenetic position inside Pan-Trionychidae is unknown." Results: "Five new specimens of Palaeoamyda messeliana nov. comb. from Messel Pit and Geiseltal localities are fully described here. A revised diagnosis for the species is also presented here, together with its inclusion in a phylogenetic analysis of Pan-Trionychidae that shows that this species is sister to the extant Amyda cartilaginea, one of the most abundant pan-trionychid (soft-shell) turtles from Asia, both members of the clade Chitrini. The specimens described in here are among the best and most complete fossil pan-trionychid skeletons so far known."
Giant extinct salmon fought with spike teeth during upriver spawning events
October 28, 2016  *This image is copyright of its original author An illustration by Jacob Biewer Credit: Society of Vertebrate Paleontology The ancient coastal waters of the Pacific, roughly 11 to 5 million years ago, were home to a bizarre and fascinating species of giant salmon with large spike-like teeth. This spike-toothed salmon reached sizes of 3 to 9 feet in length (1-3 meters), much larger than the typical salmon found in the Pacific today. These hefty spike-toothed fish would have made for a difficult catch at nearly 400 pounds (177 kg). The spike-like teeth of the salmon could be over an inch long (3 cm), much longer than modern Pacific salmon teeth, even after compensating for their larger size. Researchers from California State University in Turlock, California have been studying the strange teeth of these unusual fish and discovered some tantalizing clues into their past behavior and life history. Much like modern Pacific salmon, the giant salmon was likely primarily a filter-feeder, so the spike teeth were probably not part of catching prey. Modern salmon go through physical changes in their body, especially their skull, before migrating upriver to spawn where males will fight to defend the eggs they have fertilized. To see if these teeth played an important role in breeding of the giant fossil salmon, the team of researchers, led by Dr. Julia Sankey, compared 51 different fossils from ancient deposits of both freshwater and saltwater environments. The teeth of these salmon found in past freshwater environments consistently had longer, more recurved teeth with much larger bases, as well as showed clear signs of wear. Fossil salmon teeth from saltwater deposits were much smaller and less worn. This indicates that they changed prior to migration upriver to spawn. These results help show that these impressive spike-like teeth of the giant salmon are indeed used as part of the breeding process in these extinct fish. Researchers think it is likely these hefty bruisers were using their spike-like teeth for fighting and display against each other during the spawning season, up in the ancient rivers of California. "These giant, spike-toothed salmon were amazing fish. You can picture them getting scooped out of the Proto-Tuolumne River [near Modesto, California] by large bears 5 million years ago." said Dr. Sankey "Scientifically, our research on the giant salmon is filling in a gap in our knowledge about how these salmon lived, and specifically, if they developmentally changed prior to migration upriver like modern salmon do today. This research is also helping paint the picture of this area 5 million years ago for the general public and my college students, and it excites them to think of this giant salmon swimming up our local rivers 5 million years ago!". Dr.Sankey and colleagues presented their research at this year's meeting of the Society of Vertebrate Paleontology in Salt Lake City, Utah.  *This image is copyright of its original author An illustration by Jacob Biewer. Credit: Society of Vertebrate Paleontology  (11-06-2016, 04:03 PM)Ngala Wrote: Giant extinct salmon fought with spike teeth during upriver spawning events I didn't know that ursids (the advanced group, not Ursavus or basal ones) existed in North America five million years ago. 
The Etruscan bear (Ursus etruscus) is the direct ancestor of the brownbear (Ursus arctos). The Etruscan bear ate meat and lived from about 5.3 million years ago to about 10,000 years ago. Fossils have been found in Asia, Europe and Africa. The Etruscan bear was much smaller than today's grizzly.
http://www.bearsoftheworld.net/ursus_etruscus.asp |
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