quarta-feira, 23 de janeiro de 2019

Oldest-Known Aquatic Reptiles Might Have Spent Some Time on Land

The study of fossils of Older Mesosaurs reflects that the adult reptiles didn’t spend most of their time in the sea.

The reptiles who secondarily adapt to an aquatic or semi-aquatic life in a marine environment are called Aquatic Reptiles. A lot of reptiles adapted to the sea-life during the Mesozoic era including Mesosaurs, the oldest aquatic reptile known to humanity. Recently, a study was published in ‘Frontiers in Ecology and Evolution’ which suggested that this reptile might have spent some time on land, as well.
The researchers performed a detailed examination of Mesosaurs fossils and found that bones from adults share significant similarities with the land-dwelling animals. In addition to that, the relative scarcity of land-weathered fossils of large specimens supported the idea that older Mesosaurs were semi-aquatic. However, the researching team did acknowledge that the juveniles spent most of their time in the water. Professor Graciela Piñeiro, the Lead Author of this study who works at the Facultad de Ciencias, Universidad de la República, talked about this in the following words:
“Despite being considered the oldest-known fully aquatic reptile, mesosaurs share several anatomical features with terrestrial species. Our comprehensive analysis of the vertebrae and limbs of these ancient reptiles suggests they lived in the water during the earliest stages of their development, whereas mature adults spent more time on land.”
This research carries a lot of significance as it showed the world that thorough analysis of fossilized remains from all stages of a reptile’s life is necessary to completely understand the behavior and lifestyle of the creature. The discovery of unusually large bones of Mesosaurs in the Mangrullo Formation of Uruguay urged the international team of researchers to figure out the theory behind this finding. The general length of discovered skeletons was around 90 centimeters but they found some large specimens which were about 2 meters in length. They wanted to know why these mature adults were not in abundance and this curiosity led them to an amazing discovery. Piñeiro referred to that and said,
“The larger specimens, at least twice the length of the more commonly reported Mesosaurus fossils, could just be exceptionally big individuals. However, the environmental conditions of the Mangrullo lagoon of where they lived were harsh, making it difficult for the occasional mesosaur to reach such a relatively large size and age. We then realized that in comparison to the smaller, better-preserved specimens, larger Mesosaurus fossils were almost always disarticulated, very weathered and badly preserved. This suggested these larger specimens had extended exposure to the air when they died.
Different life stages of this ancient reptile were catered in this research to ensure all aspects are covered, thoroughly. The researchers tried to look for signs of terrestrial existence during the reconstruction and analysis of Mesosaurs skeletons. The skeletal structure is extremely important in determining the habitat of the animal because there is a marked difference in bone profiles of terrestrial, semi-aquatic, and aquatic creatures.
Consequently, the team of Piñeiro took help from morphometrics to examine the shape of the fossilized bones. A total of 40 Mesosaurs specimens were selected for examination, ranging from juveniles to adults, and all of them were compared to similar aquatic or semi-aquatic reptiles. Pablo Núñez, a member of the team at Universidad de la República, explained the results by saying,
The adult mesosaur tarsus (a cluster of bones in the ankle region) suggests a more terrestrial or amphibious locomotion rather than a fully aquatic behavior as widely suggested before. Their caudal vertebrae, the tail bones, also showed similarities to semi-aquatic and terrestrial animals. This supports the hypothesis that the oldest and largest mesosaurs spent more time on land, where fossil preservation is not as good as in the subaquatic domain.
According to Piñeiro, this research is of immense importance not only for the future research but also for understanding the reptile evolution. She mentioned that their work highlights that we must work with an entire population of a species before establishing any paleobiological interpretations of their behavior. She also talked about the implications of this research on the species that are closely related to the Mesosaurs. In particular, she talked about the evolution of the amniotic egg and said,
“For instance, thanks to our previous discovery of a mesosaur egg and embryos inside the mother’s body, our new findings can give support to earlier hypotheses suggesting that the amniotic egg might have appeared in aquatic or semiaquatic animals as a strategy to leave the water to avoid predation.

Livro destaca a importância das pequenas plantas para o Cerrado

Obra de professora da Unesp encanta e conscientiza leitores com belas imagens e informação

22/01/2019 por: José Tadeu Arantes | Agência FAPESP
Livro é destinado à distribuição gratuita para bibliotecas, institutos de pesquisa e estudioso, além de estar disponível em PDF. Imagem: Reprodução
 
 “As pessoas só dão valor para aquilo que conhecem.” Foi este pensamento que inspirou a pesquisadora Giselda Durigan a coordenar a empreitada coletiva que resultou no livro Plantas pequenas do Cerrado: biodiversidade negligenciadaCom 720 páginas, quase todas ilustradas com deslumbrantes fotos coloridas, o livro apresenta um levantamento exaustivo das plantas de pequeno porte, que são o sustentáculo do Cerrado.

Professora em programas de pós-graduação em Ciência Florestal na Universidade Estadual Paulista (Unesp) e em Ecologia na Universidade Estadual de Campinas (Unicamp), ela estuda o Cerrado há mais de 30 anos.

Destinada à distribuição gratuita para bibliotecas, institutos de pesquisa e estudiosos, e também disponibilizada em arquivo PDF aberto para todos os interessados, a obra teve sua publicação financiada pela Secretaria do Meio Ambiente do Estado de São Paulo.

Durigan, que também é pesquisadora do Instituto Florestal do Estado de São Paulo, explica que a publicação é resultado de quase uma década de trabalho a várias mãos, que se iniciou com uma pesquisa de doutorado sobre o impacto da invasão das fisionomias campestres do Cerrado por árvores de pinus e ganhou corpo ao longo de três outras pesquisas apoiadas pela FAPESP.

Foram elas: “Avaliação do potencial de remanescentes naturais como fontes de propágulos para a restauração de fisionomias campestres de cerrado”; “Invasão do campo cerrado por braquiária (Urochloa decumbens): perdas de diversidade e experimentação de técnicas de restauração”; e “Efeito da queima prescrita e da geada sobre a diversidade e estrutura do estrato herbáceo-arbustivo do Cerrado”.

“Quando nos engajamos nessas pesquisas, percebemos que o grande impacto causado pelas invasões biológicas [Saiba mais em agencia.fapesp.br/27156/] e pela supressão do fogo [Mais informações em agencia.fapesp.br/26325/] não se dava sobre árvores, mas sobre as plantas pequenas do campo. E isso constituiu um enorme desafio, porque a nomenclatura e a classificação dessas plantas eram largamente desconhecidas. Eu tinha passado toda a minha vida profissional olhando para cima, para as árvores. Tive, então, que olhar para baixo, e com muito respeito”, disse Durigan à Agência FAPESP.

O grupo que coordenou na feitura do livro foi constituído por suas alunas Natashi Aparecida Lima Pilon e Geissianny Bessão de Assis, e por seus colegas Flaviana Maluf de Souza e João Batista Baitello.
“O que chamamos de ‘plantas pequenas’ são espécies que se tornam adultas e capazes de se reproduzir com menos de 2 metros de altura. Foi um critério arbitrário que adotamos. Começamos coletando essas plantas, e inventando nomes provisórios para elas, enquanto corríamos atrás de pessoas que pudessem nos ajudar na identificação”, contou Durigan.

Mas não foi nada fácil encontrar essas pessoas, conta a pesquisadora. Simplesmente, não havia especialistas em plantas pequenas. Foi preciso recorrer a manuais, monografias, livros antigos e ao famoso Dicionário das Plantas Úteis do Brasil, em seis volumes, publicado por Manoel Pio Corrêa no início do século passado.

“Encontramos plantas que nunca tinham sido registradas no Estado de São Paulo e outras que não eram coletadas há várias décadas. Mas não achamos nenhuma espécie nova, desconhecida pela ciência. Todas já tinham seus nomes científicos. Porém, foi uma busca tremenda descobrir os nomes populares. Muitas das plantas que encontramos estavam classificadas como ‘daninhas’ nesses livros antigos, porque a perspectiva adotada era a de quem queria cultivar o Cerrado com pastagens ou agricultura”, disse Durigan.

Um termo curioso encontrado foi o “mata-pasto”, que nomeava nada menos do que sete espécies diferentes, todas elas muito resistentes. Como essas plantas rebrotam inúmeras vezes depois de cortadas, eram consideradas daninhas. E o nome popular que receberam invertia a ordem cronológica, como se o pasto tivesse aparecido antes e as plantas surgissem depois para atrapalhar, quando havia sido exatamente o contrário.

“O que as pessoas não entendiam – e temos feito um esforço enorme para esclarecer – é que essas plantas de pequeno porte são fundamentais para a sobrevivência do Cerrado e da extraordinária riqueza que ele possui em termos de recursos hídricos e biodiversidade”, disse Durigan.
“Fala-se em desmatamento quando ocorre corte de árvores. Mas, se as plantas pequenas são erradicadas, todo o equilíbrio do Cerrado se rompe. E isso está acontecendo sem o menor impedimento porque a legislação não protege a vegetação que não tem árvores. Além disso, essa vegetação nem sequer aparece nos mapas, dadas as limitações tecnológicas para diferenciá-la de pastagens ou agricultura em imagens de satélite”, acrescentou.

Seis plantas pequenas para uma árvore

Durigan destaca que são as plantas pequenas que cobrem o solo, prevenindo a erosão pela chuva ou pelo vento.

“Elas possuem um emaranhado de raízes, facilitando a infiltração da água no solo e garantindo a saúde do ecossistema e a manutenção dos mananciais que alimentam os rios. Para ser savana, o Cerrado precisa possuir as duas camadas: a camada de árvores esparsas a meia altura e a camada de plantas pequenas cobrindo o solo”, explicou.

Segundo os autores do livro, a proporção é de seis espécies de plantas pequenas para cada espécie de árvore. Das 12.734 espécies vegetais que compõem o Cerrado, mais de 10 mil correspondem a plantas pequenas. Elas estão ameaçadas pelo adensamento das copas das árvores, resultante do manejo inadequado, e pela invasão por espécies exóticas, como o pinus e a braquiária.

O objetivo do livro é encantar os leitores com a beleza dessas plantas pequenas. E conscientizá-los acerca da necessidade de sua preservação.

O livro pode ser acessado integralmente em http://arquivo.ambiente.sp.gov.br/publicacoes/2018/12/plantaspequenasdocerrado.pdf.

terça-feira, 22 de janeiro de 2019

[Paleontology • 2019] Lisowicia bojani • An Elephant-sized Late Triassic Synapsid with Erect Limbs

Lisowicia bojani 
Sulej & Niedźwiedzki, 2018

Abstract
Here, we describe the dicynodont Lisowicia bojani, from the Late Triassic of Poland, a gigantic synapsid with seemingly upright subcursorial limbs that reached an estimated length of more than 4.5 meters, height of 2.6 meters, and body mass of 9 tons. Lisowicia is the youngest undisputed dicynodont and the largest nondinosaurian terrestrial tetrapod from the Triassic. The lack of lines of arrested growth and the highly remodeled cortex of its limb bones suggest permanently rapid growth and recalls that of dinosaurs and mammals. The discovery of Lisowicia overturns the established picture of the Triassic megaherbivore radiation as a phenomenon restricted to dinosaurs and shows that stem-group mammals were capable of reaching body sizes that were not attained again in mammalian evolution until the latest Eocene.



Illustration: Julius Csotonyi 
Lisowicia bojani gen. et sp. nov., hind limb elements (femur, fibula, tibia) preserved in situ, upper bone-bearing interval, Lipie Śląskie clay-pit at Lisowice.
Artistic reconstruction of Lisowicia bojani, front view.
Illustration: Karolina Suchan-Okulska
Systematic paleontology
 Synapsida Osborn, 1903 
Therapsida Broom, 1905 
Anomodontia Owen, 1860 
Dicynodontia Owen, 1860 
Placeriinae King, 1988 
Lisowicia gen. nov. 

Type species. Lisowicia bojani sp. nov.
Diagnosis. The dicynodont differs from all other dicynodonts as it possesses the following unique combination of character states, visible in the holotype (ZPAL V.33/96, left humerus): 1) the humerus has a narrower entepicondyle in comparison with other dicynodonts (autapomorphy); 2) the entepicondylar foramen of the humerus is absent (autapomorphy); 3) the supinator process is longer (it is 31% of the total humerus length) than in other dicynodonts. 

Lisowicia bojani sp. nov. 

Etymology. Lisowicia, from the name of the village Lisowice where the bones were found; bojani, in honor of Ludwig Heinrich Bojanus (1776–1827), comparative anatomist and paleontologist.

Age. Late Norian-earliest Rhaetian, Late Triassic.
....
Tomasz Sulej and Grzegorz Niedźwiedzki. 2018. An Elephant-sized Late Triassic Synapsid with Erect Limbs. Science. 363(6422); 78-80.  DOI:  10.1126/science.aal4853
Scientists find remains of huge ancient herbivore phys.org/news/2018-11-scientists-huge-ancient-herbivore.html via @physorg_com

[PaleoMammalogy • 2018] Maiabalaena nesbittae • Tooth Loss Precedes the Origin of Baleen in Whales

Maiabalaena nesbittae 
 Peredo, Pyenson, Marshall & Uhen, 2018

 Illustration: Alex Boersma (AlexBoersma.com)
Highlights
• Maiabalaena nesbittae is 33 million year old fossil baleen whale from Oregon
Maiabalaena has neither teeth, nor baleen
• Early whales lost teeth entirely before the evolutionary origin of baleen
• Despite no teeth or baleen, these whales were effective suction feeders
Summary
Whales use baleen, a novel integumentary structure, to filter feed; filter feeding itself evolved at least five times in tetrapod history but demonstrably only once in mammals. Living baleen whales (mysticetes) are born without teeth, but paleontological and embryological evidence demonstrate that they evolved from toothed ancestors that lacked baleen entirely. 
 
The mechanisms driving the origin of filter feeding in tetrapods remain obscure. Here we report Maiabalaena nesbittae gen. et sp. nov., a new fossil whale from early Oligocene rocks of Washington State, USA, lacking evidence of both teeth and baleen. The holotype possesses a nearly complete skull with ear bones, both mandibles, and associated postcrania. Phylogenetic analysis shows Maiabalaena as crownward of all toothed mysticetes, demonstrating that tooth loss preceded the evolution of baleen. The functional transition from teeth to baleen in mysticetes has remained enigmatic because baleen decays rapidly and leaves osteological correlates with unclear homology; the oldest direct evidence for fossil baleen is ∼25 million years younger than the oldest stem mysticetes (∼36 Ma). Previous hypotheses for the origin of baleen are inconsistent with the morphology and phylogenetic position of Maiabalaena. The absence of both teeth and baleen in Maiabalaena is consistent with recent evidence that the evolutionary loss of teeth and origin of baleen are decoupled evolutionary transformations, each with a separate morphological and genetic basis. Understanding these macroevolutionary patterns in baleen whales is akin to other macroevolutionary transformations in tetrapods such as scales to feathers in birds.
Keywords: baleen, cetacea, filter-feeding, mysticeti, suction feeding
Figure 1. Cranial Elements of the Holotype of Maiabalaena nesbittae, USNM 314627.
Systematics 
Cetacea; Pelagiceti; 
Neoceti; Mysticeti; 
Maiabalaena nesbittae gen. et sp. nov. 
Etymology: Maiabalaena combines Maia-, meaning mother, and -balaena, meaning whale. Named for its phylogenetic position as basal to baleen-bearing mysticetes. The specific epithet nesbittae honors Dr. Elizabeth A. Nesbitt for her lifetime of contribution to paleontology of the Pacific Northwest and her mentorship and collegiality at the Burke Museum of Natural History and Culture in Seattle, Washington, USA.
 3D models of select specimens in lateral view with artistic reconstructions of their feeding modes:
 (B) Basilosaurus isis; (C) Coronodon havensteini; (D) Maiabalaena nesbittae; and (E) Balaenoptera musculus.

These panels illustrate the loss of a functional dentition, the intermediate phase with neither teeth nor baleen, and the subsequent origin of baleen. Illustrations are original artwork by Alex Boersma (www.alexboersma.com).
Figure 2. Phylogenetic Relationships of Stem Mysticetes Illustrating the Evolutionary Loss of Teeth and Subsequent Origin of Baleen Figure illustrates a composite phylogeny including results from this analysis (Figure S4) and recently published analyses.
(A) Time calibrated simplified phylogeny, with collapsed clade resolution for Mammalodontidae, Aetiocetidae and Eomysticetidae, and crown Mysticeti.
 (B–E) Colored bars indicate groups figured; gray bars indicate groups not figured. Panels (b–e) represent 3D models of select specimens in lateral view with artistic reconstructions of their feeding modes: (B) Basilosaurus isis; (C) Coronodon havensteini; (D) Maiabalaena nesbittae; and (E) Balaenoptera musculus. These panels illustrate the loss of a functional dentition, the intermediate phase with neither teeth nor baleen, and the subsequent origin of baleen. Illustrations are original artwork by Alex Boersma (www.alexboersma.com).
This is an artistic reconstruction of a mother and calf of Maiabalaena nesbittae nursing offshore of Oregon during the Oligocene, about 33 million years ago. While Maiabalaena would not have been able to chew or filter feed, muscle attachments on the bones of its throat indicate it likely had strong cheeks and a retractable tongue. These traits would have enabled it to suck water into its mouth, taking up fish and small squid in the process. The ability to suction feed would have rendered teeth, whose development requires a lot of energy to grow, unnecessary. The loss of teeth, then, appears to have set the evolutionary stage for the baleen, which the scientists estimate arose about 5 to 7 million years later.
 Illustration: Alex Boersma (www.alexboersma.com)
 Carlos Mauricio Peredo, Nicholas D. Pyenson, Christopher D. Marshall and Mark D. Uhen. 2018. Tooth Loss Precedes the Origin of Baleen in Whales. Current Biology.  DOI: 10.1016/j.cub.2018.10.047
Whales Lost Their Teeth Before Evolving Hair-like Baleen in Their Mouths  si.edu/newsdesk/releases/whales-lost-their-teeth-evolving-hair-baleen-their-mouths via @Smithsonian
Toothless, 33-Million-Year-Old Whale Could Be an Evolutionary ‘Missing Link’  gizmodo.com/toothless-33-million-year-old-whale-could-be-an-evolut-1830739126 via @gizmodo
    

[Paleontology • 2018] Volgatitan simbirskiensis • The Oldest Titanosaurian Sauropod of the Northern Hemisphere


Volgatitan simbirskiensis
Averianov & Efimov, 2018

"Titanosaur" by Olorotitan 
ABSTRACT
Volgatitan simbirskiensis, gen. et sp. nov., is described based on a series of anterior and middle caudal vertebrae from a single individual discovered in the Lower Cretaceous (upper Hauterivian, Speetoniceras versicolor ammonite Zone) marine deposits at Slantsevy Rudnik vertebrate locality near Ulyanovsk City, Russia. The new taxon is characterized by strongly procoelous anterior and middle caudal vertebrae, a long centrum of the first caudal vertebra, a strong ventral ridge in the anterior and middle caudal vertebrae, a neural arch positioned at the anterior half of the centrum, hyposphene-hypantrum articulation in the anterior caudal vertebrae, and somphospondylous bone texture. Phylogenetic analysis places the new taxon as a lithostrotian titanosaur, a basal member of the lineage leading to the Lognkosauria. This lineage previously contained only South American taxa with body mass reaching 60–70 tons. Volgatitan gen. nov. is the first European and the geologically oldest representative of this lineage. Its body mass is estimated as 17.3 tons. Discovery of Volgatitan gen. nov. suggests that the lithostrotian lineage leading to the Lognkosauria had a wider distribution in the Early Cretaceous and became extinct everywhere except South America by the end of the Early Cretaceous.
KEYWORDS: Dinosauria, Sauropoda, Titanosauriformes, Titanosauria, Lithostrotia, Early Cretaceous, Eastern Europe, Russia
Volgatitan simbirskiensis anterior caudal vertebra (holotype),
in right lateral (A), anterior (B), left lateral (C), posterior (D), dorsal (E), and ventral (F) views. 
Alexander Averianov and Vladimir Efimov. 2018. The Oldest Titanosaurian Sauropod of the Northern Hemisphere. Biological Communications. 63(3), 145–162. DOI:  10.21638/spbu03.2018.301
Scientists from St Petersburg and Ulyanovsk have described a new giant dinosaur  english.spbu.ru/news/2482-scientists-from-st-petersburg-and-ulyanovsk-have-described-a-new-giant-dinosaur
    

[Paleontology • 2018] Saltriovenator zanellai • The Oldest Ceratosaurian (Dinosauria: Theropoda), from the Lower Jurassic of Italy, Sheds Light on the Evolution of the Three-fingered Hand of Birds

Saltriovenator zanellai 
Dal Sasso​, Maganuco & Cau, 2018

    DOI: 10.7717/peerj.5976 
Abstract 
The homology of the tridactyl hand of birds is a still debated subject, with both paleontological and developmental evidence used in support of alternative identity patterns in the avian fingers. With its simplified phalangeal morphology, the Late Jurassic ceratosaurian Limusaurus has been argued to support a II–III–IV digital identity in birds and a complex pattern of homeotic transformations in three-fingered (tetanuran) theropods. We report a new large-bodied theropod, Saltriovenator zanellai gen. et sp. nov., based on a partial skeleton from the marine Saltrio Formation (Sinemurian, lowermost Jurassic) of Lombardy (Northern Italy). Taphonomical analyses show bone bioerosion by marine invertebrates (first record for dinosaurian remains) and suggest a complex history for the carcass before being deposited on a well-oxygenated and well-illuminated sea bottom. Saltriovenator shows a mosaic of features seen in four-fingered theropods and in basal tetanurans. Phylogenetic analysis supports sister taxon relationships between the new Italian theropod and the younger Early Jurassic Berberosaurus from Morocco, in a lineage which is the basalmost of Ceratosauria. Compared to the atrophied hand of later members of Ceratosauria, Saltriovenator demonstrates that a fully functional hand, well-adapted for struggling and grasping, was primitively present in ceratosaurians. Ancestral state reconstruction along the avian stem supports 2-3-4-1-X and 2-3-4-0-X as the manual phalangeal formulae at the roots of Ceratosauria and Tetanurae, confirming the I–II–III pattern in the homology of the avian fingers. Accordingly, the peculiar hand of Limusaurus represents a derived condition restricted to late-diverging ceratosaurians and cannot help in elucidating the origin of the three-fingered condition of tetanurans. The evolution of the tridactyl hand of birds is explained by step-wise lateral simplification among non-tetanuran theropod dinosaurs, followed by a single primary axis shift from digit position 4 to 3 at the root of Tetanurae once the fourth finger was completely lost, which allowed independent losses of the vestigial fourth metacarpal among allosaurians, tyrannosauroids, and maniraptoromorphs. With an estimated body length of 7.5 m, Saltriovenator is the largest and most robust theropod from the Early Jurassic, pre-dating the occurrence in theropods of a body mass approaching 1,000 Kg by over 25 My. The radiation of larger and relatively stockier averostran theropods earlier than previously known may represent one of the factors that ignited the trend toward gigantism in Early Jurassic sauropods.
Figure 1: Fossil location and geological setting. (A–C) Outline maps of Italy, Lombardy, Varese Province, and Saltrio Municipality; (D) satellite view of the Saltrio area, with map marker indicating the Saltrio quarry; (E) map marker indicating the stratigraphic log in the Saltrio quarry; (F) the ammonite Paracoroniceras cf. gmuendense and (G) the nautiloid Cenoceras striatum, both found associated in the layer containing the dinosaur bones; (H) glauconite present as accessory mineral in block C (counterpart of block A of Fig. 2); (I) the discordance between the Dolomia Principale Fm. and the Saltrio Fm.; (J) thin sections of the layer embedding the dinosaur bones; (K) stratigraphic log of the Saltrio quarry, based on Croce (2005), with geological time scale and ammonites zones based on Sacchi Vialli (1964) and Ogg & Hinnov (2012). Abbreviations: c, crinoids; f, foraminifers; g, gastropods; o, ostracods. Scale bars equal 200 km in (A), 30 km in (B), six km in (C), one km in (D), one mm in (K), and 150 cm in (L). Photos by F. Berra, G. Bindellini, M. Croce, and G. Pasini; drawings by M. Croce and S. Maganuco.
Figure 1: Fossil location and geological setting.
(A–C) Outline maps of Italy, Lombardy, Varese Province, and Saltrio Municipality.
Scale bars equal 200 km in (A), 30 km in (B), six km in (C).
Figure 1: Fossil location and geological setting.
 (D) satellite view of the Saltrio area, with map marker indicating the Saltrio quarry; (E) map marker indicating the stratigraphic log in the Saltrio quarry; (F) the ammonite Paracoroniceras cf. gmuendense and (G) the nautiloid Cenoceras striatum, both found associated in the layer containing the dinosaur bones; (H) glauconite present as accessory mineral in block C (counterpart of block A of Fig. 2); (I) the discordance between the Dolomia Principale Fm. and the Saltrio Fm.; (J) thin sections of the layer embedding the dinosaur bones; (K) stratigraphic log of the Saltrio quarry, based on Croce (2005), with geological time scale and ammonites zones based on Sacchi Vialli (1964) and Ogg & Hinnov (2012). Abbreviations: c, crinoids; f, foraminifers; g, gastropods; o, ostracods.
Scale bars equal one mm in (K), and 150 cm in (L). Photos by F. Berra, G. Bindellini, M. Croce, and G. Pasini; drawings by M. Croce and S. Maganuco.
Figure 2: Taphonomy of the Saltrio theropod (block A). Bones of Saltriovenator mapped in temporal sequence (A–C), gradually emerging from the embedding rock during acid preparation of block A. Numbers refer to each fragment, not to a specific anatomical position. The latter is reported in other figures, for fragments that were later reconnected into more complete bones. Abbreviations as in text, and as follows: ind, indeterminate bone; ir, indeterminate rib; l (left) and r (right) are specified for fragments of paired bones certainly (appendicular elements) or tentatively (ribs) positioned in the skeleton. Macroborings facing front, side and back are mapped respectively with yellow circles, semicircles, and hatched circles. Scale bars equal 10 cm. Photos by G. Bindellini and C. Dal Sasso.
Figure 4: Selected elements used in the diagnosis of Saltriovenator zanellai n. gen. n. sp. Right humerus in medial (A), frontal (B) and distal (C) views; (D) left scapula, medial view; (E) right scapular glenoid and coracoid, lateral view; (F) furcula, ventral view; tooth, labial (G) and apical (H) views; (I) left humerus, medial view; right second metacarpal in dorsal (J), lateral (L) and distal (N) views; first phalanx of the right second digit in dorsal (K), lateral (M) and proximal (O) views; (P–T) right third digit in proximal, dorsal and lateral views; (U) right distal tarsal IV, proximal view; third right metatarsal in proximal (V) and frontal (X) views; second right metatarsal, proximal (W) and frontal (Y) views; (Z) reconstructed skeleton showing identified elements (red).
Abbreviations as in text, asterisks mark autapomorphic traits. 
Scale bars: 10 cm in (A)–(E), (I), and (U)–(Y); two cm in (F), and (J)–(T); one cm in (G). 
Photos by G. Bindellini, C. Dal Sasso and M. Zilioli; drawing by M. Auditore.
Figure 5: Cranio-mandibular fragments, tooth, and ribs of Saltriovenator zanellai. Indeterminate cranial fragment (A–B); right splenial in lateral (C), rostral (D) and ventral (E) views; right prearticular in lateral (F) and rostral views (G); sketch of the right prearticular of MOR 693 (Allosaurus fragilis) with virtual cross-section (H) diagnostic for G, also confirmed by CT slicing of the left side element of MOR 693 (I); splenial and prearticular in medial view, positioned in a reconstructed right lower jawof Saltriovenator (J). Maxillary or dentary tooth in labial (K) and apical (L) views; close-up of the distal carina and denticles in lingual (M) and distal (N) views. Left cervical rib (O) in craniolateral view; fragmentary right (P) and left (Q) dorsal ribs in craniolateral view.
Abbreviations as in text, ribs labeled as in Fig. 2 maps and caption. Scale bars equal two cm in (A)–(I), five cm in (J), one cm in (K), five mm in (L), one mm in (M)–(N), five cm in (O)–(Q). 
Photos by G. Bindellini, C. Dal Sasso, and M. Zilioli; drawing by C. Dal Sasso.
Systematic Paleontology

DINOSAURIA Owen, 1842
THEROPODA Marsh, 1881
NEOTHEROPODA Bakker, 1986
CERATOSAURIA Marsh, 1884
Saltriovenator zanellai gen. et sp. nov.

Etymology. Saltrio, Italian toponym name, from the locality where the holotype was found; venator, Latin word for hunter, it also refers to a type of Roman gladiator; zanellai, Latin genitive dedicated to Angelo Zanella, who discovered the fossil.

Holotype. MSNM V3664, very fragmentary and disarticulated skeleton (Figs. 4–13), represented by the following elements (among brackets, number of fragments per bone): partial right splenial (2) and right prearticular (1); cervical (1) and dorsal (9) ribs; furcula (1), incomplete left scapula (16), right scapular glenoid (1), partial right coracoid (5), fragmentary right sternal plate (2); right humerus (2), and proximal half of left humerus (2); ?right ?distal carpal, right metacarpal II, right phalanx II-1, fragmentary right phalanx II-2, and tip of the ?second right ungual phalanx; complete third right manual digit (phalanges III-1 to III-4); right distal tarsals III and IV, proximal portions of right metatarsals II, III, IV, and V(2).

Referred material. MSNM V3659, one maxillary or dentary tooth (Figs. 4 and 5).

Comments. As noted above, the discovery of all skeletal elements at the same time in a very restricted spot, the fact that all of them are of matching size, and that fragmentary and anatomically adjacent elements are of matching morphology, leave no doubt that all bones referred to the holotype come from the same individual. We prudentially exclude from the holotype the single tooth, which was found relatively associated to the bones but lacking its root and any jaw bone connection, thus raising the doubt that it might represent a shed tooth.

Type locality. “Salnova” quarry, Saltrio, Varese Province, Lombardy (northern Italy).

Horizon and Age. Saltrio Fm. (sensu Gnaccolini, 1964), bucklandi Zone, early Sinemurian (199.3–197.5 mya) (Ogg & Hinnov, 2012).

Diagnosis. Mid-to-large sized ceratosaurian characterized by the following unique combination of anatomical features (autapomorphies marked by asterisk—see also Fig. 4): humerus with deltopectoral crest protruding craniomedially for more than twice the shaft diameter, with distal lamina forming an abrupt corner (about 90°) with the proximodistal axis of the humeral shaft; metacarpal II with hypertrofied semicircular extensor lip protruding over the condylar level* and bordering dorsolaterally a very deep and wide extensor pit; phalanx II-1 with flexor palmar groove which is deep and narrow*, and bearing a distinct bump distal to the dorsal extensor process*; manual ungual III with prominent flexor tubercle which is distinctly separated from articular facet by a concave cleft.
 .....
Simplified evolutionary tree of predatory dinosaurs (theropods). Saltriovenator predates the massive meat-eating dinosaurs by over 25 million years: it is the oldest known ceratosaurian, and the world's largest predatory dinosaur from the Lower Jurassic. During the Jurassic, the three- fingered tetanuran theropods appeared, which gave rise to birds.


Conclusions
Saltriovenator zanellai gen. et sp. nov. is a new theropod dinosaur from the Lower Jurassic of Northern Italy. It represents the third named species of non-avian dinosaur from Italy, the first of Jurassic age. Saltriovenator shows a combination of ceratosaurian and tetanuran features, supporting close relationships between the two averostran lineages with the exclusion of coelophysoid-grade theropods. It also represents the first skeletal material supporting the occurrence of large and robustly-built predatory dinosaurs just at the aftermath of the Triassic–Jurassic boundary extinction events. Accordingly, the Italian ceratosaurian fills a stratigraphic and ecomorphological gap between the relatively more gracile coelophysoid-grade neotheropods (known from the Late Triassic to the Early Jurassic) and the large-bodied averostrans that occupied the majority of the apex predatory roles in the terrestrial ecosystems between the Middle Jurassic and the end of the Cretaceous.
The phylogenetic framework integrated with the new combination of features present in Saltriovenator dismisses the “II–III–IV homology pattern” in the interpretation of the tetanuran (and avian) hand, and suggests a complex process leading to the atrophied forelimb of later ceratosaurians. The evolution of a stocky and robust hand occurred in ceratosaurians before the relative shortening and the loss of predatory function: such a step-wise scenario raises intriguing perspectives on what adaptive and developmental factors led from a “Saltriovenator-like” condition to the aberrant condition present in Limusaurus and abelisaurids.
Cristiano Dal Sasso​, Simone Maganuco and Andrea Cau. 2018. The Oldest Ceratosaurian (Dinosauria: Theropoda), from the Lower Jurassic of Italy, Sheds Light on the Evolution of the Three-fingered Hand of Birds.   PeerJ. 6:e5976.  DOI: 10.7717/peerj.5976
The oldest large-sized predatory dinosaur comes from the Italian Alps phys.org/news/2018-12-oldest-large-sized-predatory-dinosaur-italian.html via @physorg_com
Meet Saltriovenator: Oldest Known Big Predatory Dinosaur - Dead Things  bit.ly/2EuANJX


[Paleontology • 2019] Descriptive Anatomy of the Largest Known Specimen of Protoichthyosaurus prostaxalis (Reptilia: Ichthyosauria) including Computed Tomography and Digital Reconstruction of A Three-dimensional Skull


Protoichthyosaurus prostaxalis Appleby, 1979

in Lomax, Porro & Larkin, 2019.  

Abstract
Ichthyosaur fossils are abundant in Lower Jurassic sediments with nine genera found in the UK. In this paper, we describe the partial skeleton of a large ichthyosaur from the Lower Jurassic (lower Sinemurian) of Warwickshire, England, which was conserved and rearticulated to form the centrepiece of a new permanent gallery at the Thinktank, Birmingham Science Museum in 2015. The unusual three-dimensional preservation of the specimen permitted computed tomography (CT) scanning of individual braincase elements as well as the entire reassembled skull. This represents one of the first times that medical imaging and three-dimensional reconstruction methods have been applied to a large skull of a marine reptile. Data from these scans provide new anatomical information, such as the presence of branching vascular canals within the premaxilla and dentary, and an undescribed dorsal (quadrate) wing of the pterygoid hidden within matrix. Scanning also revealed areas of the skull that had been modelled in wood, clay and other materials after the specimen’s initial discovery, highlighting the utility of applying advanced imaging techniques to historical specimens. Additionally, the CT data served as the basis for a new three-dimensional reconstruction of the skull, in which minor damage was repaired and the preserved bones digitally rearticulated. Thus, for the first time a digital reconstruction of the skull and mandible of a large marine reptile skull is available. Museum records show the specimen was originally identified as an example of Ichthyosaurus communis but we identify this specimen as Protoichthyosaurus prostaxalis. The specimen features a skull nearly twice as long as any previously described specimen of P. prostaxalis, representing an individual with an estimated total body length between 3.2 and 4 m.
Figure 1: Three-dimensional skull of BMT 1955.G35.1, Protoichthyosaurus prostaxalis.
 (A) Original photograph of the first skull reconstruction (left lateral view) within a couple of years of the 1955 excavation. Note that the prefrontal and postorbital are present, which we have been unable to locate in our study. (B) Skull in left lateral view, as reconstructed in 2015. (C) Skull in right lateral view, as reconstructed in 2015. Note the distinctive asymmetric maxilla with long, narrow anterior process. Teeth are not in their original positions. Scale bar represents 20 cm.

Conclusions: 
In this study, we describe a large, partial ichthyosaur skeleton from the Early Jurassic of Warwickshire, England. In addition to examining the specimen, we carried out CT scanning of individual skull bones as well as the entire, reassembled skull, one of the first times the skull of a large marine reptile has been successfully CT-scanned, visualized and reconstructed in 3D (see McGowan, 1989; Foffa et al., 2014a). CT scanning contributed greatly to our anatomical description by revealing features not visible on original fossil material such as: branching, longitudinal vascular canals within the premaxilla and dentary; short canals penetrating the nasal, lacrimal, stapes and articular; trabecular bone within the opisthotic; canals in the basisphenoid and supraoccipital; the presence of the quadrate process of the pterygoid; and the sutural morphology. We also demonstrate the utility of applying medical imaging techniques to historic specimens to differentiate between original fossil material and reconstructed regions, as well as the advantage of using digital visualization to accurately reconstruct large fossil specimens in 3D.
The detailed description of the three-dimensional skull and braincase presented herein also provides information that can be used in phylogenetic studies. Although incomplete, the skull and braincase preserve various elements that have not previously been reported or described in any specimen of Protoichthyosaurus and therefore it provides more information about this taxon so that its phylogenetic position can be explored in more detail. Furthermore, our study has found additional characters that may lend further support for the distinction of Protoichthyosaurus from its sister taxon Ichthyosaurus, such as the morphology of the pterygoid and anteroventral surface of the parietal, which differ from that described for Ichthyosaurus (McGowan, 1973). However, considering that only a couple of specimens preserve these elements, it is possible that the differences may be the result of individual variation; more three-dimensional specimens of both taxa are needed to test and clarify these findings.
Based on a unique combination of characters, we identify the studied specimen as P. prostaxalis. With a skull nearly twice as long as any previously described specimen of P. prostaxalis, this specimen greatly increases the known size range of this genus. Compared with known, contemporaneous Sinemurian ichthyosaurs, the estimated size suggests it was larger than all species of Ichthyosaurus (Lomax & Sachs, 2017), and comparable with the largest known specimens of Leptonectes tenuirostris (McGowan, 1996a), but smaller than L. solei (McGowan, 1993), Excalibosaurus costini (McGowan, 2003) and Temnodontosaurus platyodon (McGowan, 1996b). Thus, our study also provides new information on ichthyosaur diversity and potential ecology in the Early Jurassic of the UK.
Dean R. Lomax, Laura B. Porro and Nigel R. Larkin. 2019. Descriptive Anatomy of the Largest Known Specimen of Protoichthyosaurus prostaxalis (Reptilia: Ichthyosauria) including Computed Tomography and Digital Reconstruction of A Three-dimensional Skull.   PeerJ. 7:e6112. DOI:  10.7717/peerj.6112