[Herpetology • 2020] Kinosternon cora • A New Species of Mud Turtle of Genus Kinosternon (Testudines: Kinosternidae) from the Pacific Coastal Plain of Northwestern Mexico

Kinosternon cora 

Loc-Barragán, Reyes-Velasco, Woolrich-Piña, Grünwald, Anaya, Rangel-Mendoza & López-Luna, 2020

 Cora Mud Turtle, Casquito cora, Chacuanita cora  || DOI: 10.11646/zootaxa.4885.4.3 

Abstract

We describe a new species of mud turtle of the genus Kinosternon from the Pacific Coastal Plain of the Mexican states Sinaloa and Nayarit. The new species shares morphological characters with the recently described Kinosternon vogti, which are unique to these two turtles and separate them from the other species of the genus. The new species differs from K. vogti by skin coloration, size, and the scutellation of both carapace and plastron. We also present a molecular phylogeny of the family Kinosternidae based on two mitochondrial and four nuclear loci. Our results show that the new species is most closely related to K. vogti, and together they form the sister group to the K. hirtipes and K. integrum species groups of Kinosternon.

Keywords: Reptilia; freshwater turtle sp. nov.; endemic; Sinaloa; Nayarit; Pacific Coastal Plain

Head patterns of Kinosternon cora sp. nov. 
A: Female holotype, MZFC-HE 35627, B: Male paratype, MZFC-HE 35629. 

Unscaled images. 

Photo by M. A. López-Luna.

 

Kinosternon cora sp. nov. 

 Cora Mud Turtle, Casquito cora, Chacuanita cora  

Diagnosis—A small Kinosternon, the largest known specimen is a female (CL=107.7 mm). This species is unique among Kinosternon of western Mexico, except K. vogti, of which it is a sister species, by possessing a very reduced and weakly kinetic plastron; a narrow bridge; and a proportionally wide carapace. We describe the diagnostic characteristics of Kinosternon cora with the species present on the Mexican Pacific versant (Table 2).

.....

Further observations of Kinosternon cora sp. nov.
 Series of photographs above: Adult male observed near Rosamorada, Municipo de Rosamorada, Nayarit. Photos by J. A. Loc-Barragán.
Series of photographs below: Juvenile female observed near Chilapa, Municipio de Rosamorada, Nayarit. Photos by Jorge Larios Luquín.

Male paratype of Kinosternon cora sp. nov. MZFC-HE 35629.
Dorsal and ventral view. Black line represents 50 mm.

 Photo by M. A. López-Luna.

Known distribution of Kinosternon cora sp. nov. in Sinaloa and Nayarit. Yellow star represents the type locality, yellow dots represent additional records.

Red dots represent the records of the sister species Kinosternon vogti.

Aerial photograph (above) of the type locality of Kinosternon cora. A small temporary lake with affluent streams, surrounded by secondary vegetation (below), and invasive eucalyptus plantations originally planted for forest management.

Geographic distribution and habitat— Kinosternon cora inhabits low elevations from 10–30 m asl on the Pacific Coastal Plain adjacent to the foothills of the Sierra Madre Occidental. The predominant type of vegetation is tropical deciduous forest, with trees of 15–25 m in height. Along riparian areas tropical semi-deciduous forest is present, with Enterolobium sp., Ficus sp. and Taxodium mucronatum trees, which may reach a height of 30 m or more. Many trees and shrubs carry epiphytes and parasites. Eucalyptus crops have been planted in a large area near the type locality of Kinosternon cora (Fig. 7).

Etymology— The specific epithet is derived from the name “Cora”, the Native-Mexican ethnic group that is most widespread in Nayarit. The ethnic Cora population is concentrated in the municipalities of El Nayar, Acaponeta, Rosamorada and Ruiz, all of which are in Nayarit, the state where this new species was first discovered in 1962.

Jesús A. Loc-Barragán, Jacobo Reyes-Velasco, Guillermo A. Woolrich-Piña, Christoph I. Grünwald, Myriam Venegas de Anaya, Judith A. Rangel-Mendoza and Marco A. López-Luna. 2020. A New Species of Mud Turtle of Genus Kinosternon (Testudines: Kinosternidae) from the Pacific Coastal Plain of Northwestern Mexico. Zootaxa. 4885(4); 509–529. DOI: 10.11646/zootaxa.4885.4.3

RESUMEN: Describimos una nueva especie de tortuga casquito del género Kinosternon de la Llanura Costera del Pacifico Mexicano en los estados de Sinaloa y Nayarit. La nueva especie comparte caracteres morfológicos con Kinosternon vogti, separandolas de las otras especies del género. Las diferencias entre la nueva especie y K. vogti incluyen la coloración, tamaño, y proporciones en los escudos del caparazón y el plastrón. También presentamos una filogenia molecular de la familia Kinosternidae basada en dos genes mitocondriales y cuatro nucleares. Nuestros resultados muestran que la nueva especie está más emparentada con K. vogti, y juntos estas especies forman el grupo hermano de los grupos de especies K. hirtipes y K. integrum. 

Palabras claves: Reptilia; Tortuga de agua dulce sp. nov.; endémica; Sinaloa; Nayarit; Llanura Costera del Pacífico

[Paleontology • 2020] Functional Adaptive Landscapes Predict Terrestrial Capacity at the Origin of Limbs

two Late Devonian early tetrapods - Ichthyostega and Acanthostega - coming out of the water to move on land. Footprints trail behind the animals to show a sense of movement. 

in Dickson, Clack, et al., 2020. 

DOI: 10.1038/s41586-020-2974-5

Artwork by Davide Bonadonna.

Abstract

The acquisition of terrestrial, limb-based locomotion during tetrapod evolution has remained a subject of debate for more than a century. Our current understanding of the locomotor transition from water to land is largely based on a few exemplar fossils such as Tiktaalik, Acanthostega, Ichthyostega and Pederpes. However, isolated bony elements may reveal hidden functional diversity, providing a more comprehensive evolutionary perspective. Here we analyse 40 three-dimensionally preserved humeri from extinct tetrapodomorphs that span the fin-to-limb transition and use functionally informed ecological adaptive landscapes to reconstruct the evolution of terrestrial locomotion. We show that evolutionary changes in the shape of the humerus are driven by ecology and phylogeny and are associated with functional trade-offs related to locomotor performance. Two divergent adaptive landscapes are recovered for aquatic fishes and terrestrial crown tetrapods, each of which is defined by a different combination of functional specializations. Humeri of stem tetrapods share a unique suite of functional adaptations, but do not conform to their own predicted adaptive peak. Instead, humeri of stem tetrapods fall at the base of the crown tetrapod landscape, indicating that the capacity for terrestrial locomotion occurred with the origin of limbs. Our results suggest that stem tetrapods may have used transitional gaits during the initial stages of land exploration, stabilized by the opposing selective pressures of their amphibious habits. Effective limb-based locomotion did not arise until loss of the ancestral ‘L-shaped’ humerus in the crown group, setting the stage for the diversification of terrestrial tetrapods and the establishment of modern ecological niches.

The aerial scene depicts two Late Devonian early tetrapods - Ichthyostega and Acanthostega - coming out of the water to move on land. Footprints trail behind the animals to show a sense of movement. 

Original artwork created by Davide Bonadonna.

 

Blake V. Dickson, Jennifer A. Clack, Timothy R. Smithson and Stephanie E. Pierce. 2020. Functional Adaptive Landscapes Predict Terrestrial Capacity at the Origin of Limbs. Nature. DOI: 10.1038/s41586-020-2974-5

Water-to-land transition in early tetrapods

A new study answers the debate: how terrestrial were early tetrapods?

 eurekalert.org/pub_releases/2020-11/hudo-wti112320.php

[PaleoOrnithology • 2020] Falcatakely forsterae • Late Cretaceous Bird from Madagascar reveals Unique Development of Beaks

 Falcatakely forsterae

O’Connor, Turner, Groenke, Felice, Rogers, Krause & Rahantarisoa, 2020

 DOI: 10.1038/s41586-020-2945-x 

  twitter.com/deeptimescience

  twitter.com/rfelice 

Abstract

Mesozoic birds display considerable diversity in size, flight adaptations and feather organization, but exhibit relatively conserved patterns of beak shape and development. Although Neornithine (that is, crown group) birds also exhibit constraint on facial development, they have comparatively diverse beak morphologies associated with a range of feeding and behavioural ecologies, in contrast to Mesozoic birds. Here we describe a crow-sized stem bird, Falcatakely forsterae gen. et sp. nov., from the Late Cretaceous epoch of Madagascar that possesses a long and deep rostrum, an expression of beak morphology that was previously unknown among Mesozoic birds and is superficially similar to that of a variety of crown-group birds (for example, toucans). The rostrum of Falcatakely is composed of an expansive edentulous maxilla and a small tooth-bearing premaxilla. Morphometric analyses of individual bony elements and three-dimensional rostrum shape reveal the development of a neornithine-like facial anatomy despite the retention of a maxilla–premaxilla organization that is similar to that of nonavialan theropods. The patterning and increased height of the rostrum in Falcatakely reveals a degree of developmental lability and increased morphological disparity that was previously unknown in early branching avialans. Expression of this phenotype (and presumed ecology) in a stem bird underscores that consolidation to the neornithine-like, premaxilla-dominated rostrum was not an evolutionary prerequisite for beak enlargement.

  Falcatakely forsterae gen. et sp. nov.

 

Patrick M. O’Connor, Alan H. Turner, Joseph R. Groenke, Ryan N. Felice, Raymond R. Rogers, David W. Krause and Lydia J. Rahantarisoa. 2020. Late Cretaceous Bird from Madagascar reveals Unique Development of Beaks. Nature.  DOI: 10.1038/s41586-020-2945-x

   twitter.com/deeptimescience/status/1331653787816132608

  twitter.com/rfelice/status/1331642756469547009

[Herpetology • 2020] Atlantihyla melissa • A Critically Endangered New Species of Polymorphic Stream Frog (Anura: Hylidae: Atlantihyla) from the Montane Rainforest of Refugio de Vida Silvestre Texiguat, Honduras

Atlantihyla melissa

Townsend, Herrera-B., Hofmann, Luque-Montes, Ross, Dudek, Krygeris, Duchamp & Wilson, 2020

 DOI: 10.26049/VZ70-4-2020-12 

 facebook.com/JosiahTownsend 

   twitter.com/ErichPHofmann 

The Chortís Highlands of Mesoamerica exhibit a high degree of in situ evolutionary diversification, exemplified by numerous endemic radiations of stream-dwelling treefrogs (Anura: Hylidae: Atlantihyla, Duellmanohyla, and Ptychohyla), which have been a source of ongoing taxonomic uncertainty. Recent evidence suggests that one species, Atlantihyla spinipollex, may conceal an unrecognized sister species found in Refugio de Vida Silvestre Texiguat. We applied an iterative integrative taxonomic framework to assess this population within the context of Chortís Highlands populations of Atlantihyla spinipollex sensu stricto, Duellmanohyla salvadorensis, D. salvavida, D. soralia, and Ptychohyla hypomykter, using both a single locus (mtDNA: 16S) and multilocus (mtDNA: 12S, 16S; nDNA: POMC, RAG-1, Rhodopsin) datasets accompanied by distance- and tree-based species delimitation methods to inform our taxonomy. Samples of A. spinipollex sensu lato formed two deeply divergent monophyletic lineages, suggesting that populations from the central and eastern Cordillera Nombre de Dios are conspecific, while the population from Refugio de Vida Silvestre Texiguat represents a previously undescribed species. We analyzed morphological and bioacoustic variation within and between the two lineages of A. spinipollex sensu lato and found support for recognition of two distinct taxa. We restricted the name A. spinipollex to populations in the central and eastern Cordillera Nombre de Dios, and formally describe the Texiguat population as a new species. We recommend the new species be considered Critically Endangered due to ongoing habitat loss within what remains of its highly restricted natural distribution. This new species joins 26 other endemic species of amphibians and reptiles at Texiguat.

Key words: Atlantihyla melissa sp. nov., Atlantihyla spinipollex, Chortís Block Highlands, Cordillera Nombre de Dios, Ptychohyla hypomykter, Refugio de Vida Silvestre Texiguat.

The known distribution of focal taxa in the Chortís Block. Filled shapes indicate localities with molecular (at least 16S) sequence data generated or utilized herein; additional historical records (with no sequence data) are indicated by white shapes. Numbers and grayshaded areas refer to relevant localities within the Cordillera Nombre de Dios as follows: 1 = Refugio de Vida Silvestre Texiguat; 2 = Parque Nacional Pico Bonito; 3 = Parque Nacional Nombre de Dios; 4 = Cerro Corre Viento; 5 = Parque Nacional Capiro y Calentura. TL = type locality.

Fig. 3. Multilocus Bayesian phylogram based on combined mtDNA (12S, 16S) + nDNA (POMC, RAG-1, RHO) dataset; maximum likelihood bootstrap support values (0– 100) and Bayesian posterior probabilities (0– 1.0) shown above corresponding branches.

Photos from top to bottom: D. salvavida from Río Jilamito, Dept. Atlántida, Honduras © JHT; D. soralia from Merendón, Dept. Cortés, Honduras © JHT; holotype of Atlantihyla melissa © JHT; A. spinipollex from Cerro Corre Viento, Dept. Colón, Honduras © Jason M. Butler; Ptychohyla hypomykter from Rio Negro de Comayagua, Dept. Comayagua, Honduras (© JHT).

Adult male holotype of Atlantihyla melissa (USNM 578679; SVL = 34.4 mm), shown in life (left) and in dorsal (top right) and ventral (bottom right) aspects after eight years in preservation (photos: Josiah H. Townsend).

Paratypes of Atlantihyla melissa in life: 
(a) adult female (USNM 578676), (b) adult female (USNM 578672),
(c) adult female (USNM 578665), (d) adult female (USNM 578686),
(e) adult male (USNM 578674), (f) adult female (USNM 578668)

(photographs: Josiah H. Townsend).

Atlantihyla melissa sp. nov.

Etymology. We name this species in honor of our friend and collaborator, Isis Melissa Medina-Flores, a feld biologist originally from Mangulile in the Department of Olancho, Honduras. Melissa participated in the discovery and description of this new species, two other Texiguat endemics: the palm-pitviper Bothriechis guifarroi Townsend, Medina-Flores, Wilson, Jadin & Austin, 2013, and the centipede snake Tantilla olympia Townsend, Wilson, Medina-Flores & Herrera-B., 2013; and two salamanders endemic to the Department of Olancho: Nototriton mime Townsend, Medina-Flores, Reyes-Calderón & Austin, 2013, and N. picucha Townsend, Medina-Flores, Murillo, and Austin, 2011. Melissa disappeared without a trace on 5 November 2016, after becoming separated from her companions while descending from the summit of the highest peak in Honduras, Cerro de Las Minas in Parque Nacional Celaque. Despite over a month of continuous searching by military and volunteer rescue teams supported by search dogs and aircraft, no evidence of Melissa’s fate has been found.

Fig. 9. a) Type locality of Atlantihyla melissa, the Río Jilamito, Departamento de Atlántida, Honduras, 1,030 m a.s.l.; holotype was collected on a palm frond in the vegetation on the left side of the image. b) Adult male Atlantihyla melissa (not collected) photographed in situ on vegetation directly overhanging a small tributary of the Río Jilamito, 1,060 m a.s.l.

(photographs: Josiah H. Townsend).

 

     

Large pool in the Río Jilamito, just above the type locality; tadpoles of Atlantihyla melissa. Duellmanohyla salvavida, and Plectrohyla chrysopleura were found here in April 2017, June 2010, and July 2010.

Josiah H. Townsend, Luis A. Herrera-B., Erich P. Hofmann, Ileana R. LuqueMontes, Ayla N. Ross, Daniel Dudek, Jr., Catherine Krygeris, Joseph E. Duchamp and Larry David Wilson. 2020. A Critically Endangered New Species of Polymorphic Stream Frog (Anura: Hylidae: Atlantihyla) from the Montane Rainforest of Refugio de Vida Silvestre Texiguat, Honduras.  Vertebrate Zoology. 70(4): 731-756. DOI: 10.26049/VZ70-4-2020-12

facebook.com/JosiahTownsend/posts/10118862257032521

 facebook.com/groups/83723428145/permalink/10160389405868146

 twitter.com/ErichPHofmann/status/1329811198053937153

Description (es): Las tierras altas Chortís en Centro América presentan un alto grado de diversificación evolutiva in situ, demostrado por un numero de radiaciones endémicas de ranas arborícolas asociadas con ecosistemas lóticos (Anura: Hylidae: Atlantihyla, Duellmanohyla y Ptychohyla), y previamente han sido fuente de incertidumbre. Evidencia reciente sugiere que una especie, Atlantihyla spinipollex, podría ocultar un especie hermana no reconocida, en el Refugio de Vida Silvestre Texiguat. Aplicamos un modelo iterativo taxonómico integrativo para evaluar esta población dentro del contexto de las poblaciones de las Tierras Altas Chortís de Atlantihyla spinipollex sensu stricto, Duellmanohyla salvadorensis, D. salvavida, D. soralia, y Ptychohyla hypomykter, utilizando ambos, conjuntos de datos con locus génicos individuales (mtDNA: 16S) y conjuntos de datos con múltiple loci (mtDNA: 12S, 16S; nDNA: POMC, RAG-1, Rhodopsin), acompañados por métodos de delimitación de especies basados en distancia y arboles filogenéticos. Las muestras de A. spinipollex sensu lato formaron dos linajes monofiléticos profundamente divergentes, sugiriendo que las poblaciones del centro y Este de la Cordillera Nombre de Dios son conspecíficas, mientras que la población del Refugio de Vida Silvestre Texiguat representa un linaje a nivel de especie no descrito previamente. Analizamos la variación morfológica y bioacústica dentro y entre los dos linajes de A. spinipollexsensu lato y encontramos un fuerte soporte estadístico para el reconocimiento de dos taxones distintos. Restringimos el nombre A. spinipollex a las poblaciónes del centro y el Este de la Cordillera Nombre de Dios, y formalmente describimos la población del Refugio de Vida Silvestre Texiguat como una especie nueva. Recomendamos que la nueva especies sea considerada En Peligro Critico debido a la amenaza inmediata y continua de pérdida de hábitat dentro de su distribución natural altamente restringida. Esta nueva especie se une a otras 26 especies endémicas de anfibios y reptiles en Texiguat.

      

     

[Invertebrate • 2020] Duobrachium sparksae • A New Genus and Species of Benthopelagic Ctenophore (Ctenophora: Tentaculata: Cydippida) seen at 3,910 m Depth off the Coast of Puerto Rico

 Duobrachium sparksae  

Ford, Bezio & Collins, 2020

 DOI 10.3800/pbr.15.296 

 fisheries.noaa.gov 

 

Abstract

On April 10, 2015, three individuals of an undescribed species of ctenophore were observed moving just above the seafloor in the Arecibo Amphitheater inside the Guajataca Canyon, north-northwest of Puerto Rico at a depth of approximately 3,900 m. The ctenophore is distinctive; having two prominent tentacle arms, a body that is rectangular when observed laterally along the tentacular plane, and rounded when observed laterally along the stomodeal plane. The tentacle arms each give rise to an extensible tentacle bearing short tentilla of uniform length and distribution. One ctenophore appeared to be anchored to the seafloor by its two long flexible tentacles, as well as by two filaments exiting its oral end. The overall form of the ctenophore suggests classification within the problematic, non-monophyletic order Cydippida, but the robust tentacle arms are more reminiscent of benthic species of Platyctenida, particularly those of families Lyroctenidae and Ctenoplanidae. Whereas most platyctenid ctenophores do not possess ctene rows in their adult forms, features that are possessed by the new species described herein, species of Ctenoplanidae retain comb rows as adults and are capable of limited swimming. The species described herein is easily distinguishable from all other known species of Ctenophora and may trace its origin to a lineage diverging near the origin of Platyctenida.

Keywords: Aricebo Amphitheater, Ctenophora, Duobrachium sparksae gen nov. & spec. nov., Puerto Rico, Cydippida

Still captured from video observation of  Duobrachium sparksae n. gen. n. sp.
  Second sighting (USNM 1607332) showing regular tentilla of tentacles and large embryos/eggs within gonads, highlighting the quality of the HD video. 17:37:36 UTC.

Digital illustration of the habit of  Duobrachium sparksae n. gen. n. sp.
 A. tentacular view B. stomodeal view.

Illustrations by Nicholas Bezio.

Phylum Ctenophora Eschscholtz, 1829 

Class Tentaculata Eschscholtz, 1825 

Order Cydippida Gegenbaur, 1856 

Family Cydippida incertae sedis 

Genus Duobrachium gen. nov. 

Diagnosis. Tentaculate cydippid ctenophores with two thick, aboral, conical tentacle arms. Tentacle arms emerge from the center of the body and extend aborally. Body rectangular in the tentacular plane, oblong in the stomodeal plane. The tentacle arms are as long as the body is tall. Tentacles retractile, with simple tentilla of uniform length. Filaments can exit orally, anchoring it to the sediment. Stomodeum darkly pigmented. Gonads globular, not extending the length of the meridional canals. 

 

Etymology. From the Latin “two-arms”, a name reflecting the two prominent arms. The Latin “brachium” is of common gender, but shall be treated as feminine, in accordance with ICZN article 30.1.4.2.

Line drawing schematic of Duobrachium sparksae n. gen. n. sp.
 A. Tentacular view of the main body of the animal. B. Oral view. C. Aboral view.

ct - ctene row, g - gonads, m - mouth, ta - tentillum, tent - tentacle, stat - statocyst, sto - stomodeum.

 Illustrations by Nicholas Bezio.

 Duobrachium sparksae spec. nov.

Etymology. The specific epithet “sparksae” honors Elizabeth Ann Sparks, the wife of Michael Ford. Common name. Sparks’ two-armed ctenophore. 

Distribution. Only known from Guajataca Canyon, north-northwest of Puerto Rico at a depth of approximately 3,900 m, within meters of the seafloor 

 

Michael Ford, Nicholas Bezio and Allen Collins. 2020. Duobrachium sparksae (incertae sedis; Ctenophora: Tentaculata: Cydippida): A New Genus and Species of Benthopelagic Ctenophore seen at 3,910 m Depth off the Coast of Puerto Rico. Plankton and Benthos Research. 15(4); 296-305. DOI 10.3800/pbr.15.296  

 

NOAA Scientists Virtually Discover New Species of Comb Jelly Near Puerto Rico

fisheries.noaa.gov/feature-story/noaa-scientists-virtually-discover-new-species-comb-jelly-near-puerto-rico

twitter.com/RebeccaRHelm/status/1330927733677895681

[Paleontology • 2020] Bagualia alba • Extinction of Herbivorous Dinosaurs linked to Early Jurassic Global Warming Event

Bagualia alba 

Pol, Ramezani, Gomez, Carballido, Carabajal, Rauhut, Escapa & Cúneo, 2020

DOI: 10.1098/rspb.2020.2310

 Illustration:  Jorge Gonzales 

twitter.com/PolDiego

MEF.org.ar 

Abstract

Sauropods, the giant long-necked dinosaurs, became the dominant group of large herbivores in terrestrial ecosystems after multiple related lineages became extinct towards the end of the Early Jurassic (190–174 Ma). The causes and precise timing of this key faunal change, as well as the origin of eusauropods (true sauropods), have remained ambiguous mainly due to the scarce dinosaurian fossil record of this time. The terrestrial sedimentary successions of the Cañadón Asfalto Basin in central Patagonia (Argentina) document this critical interval of dinosaur evolution. Here, we report a new dinosaur with a nearly complete skull that is the oldest eusauropod known to date and provide high-precision U–Pb geochronology that constrains in time the rise of eusauropods in Patagonia. We show that eusauropod dominance was established after a massive magmatic event impacting southern Gondwana (180–184 Ma) and coincided with severe perturbations to the climate and a drastic decrease in the floral diversity characterized by the rise of conifers with small scaly leaves. Floral and faunal records from other regions suggest these were global changes that impacted the terrestrial ecosystems during the Toarcian warming event and formed part of a second-order mass extinction event.

Keywords: Eusauropoda, Toarcian, Pliensbachian, Sauropoda

  Systematic palaeontology

Dinosauria Owen, 1842; 

Sauropoda Marsh, 1878; 

Eusauropoda Upchurch, 1995

Bagualia alba gen. et sp. nov.

Etymology: bagual, wild horse (Spanish), for the type locality; alba, dawn (Spanish) in allusion to its early age.

Holotype: MPEF-PV 3301, posterior half of skull articulated with seven cervical vertebrae (Museo Paleontológico Egidio Feruglio, Trelew, Argentina).

Locality and Horizon: Bagual Canyon, 5 km south of Cerro Cóndor, Chubut, Argentina. Lower levels of the Cañadón Asfalto Formation dated at 179.17 ± 0.12 Ma (see below and electronic supplementary material), Early Jurassic, Toarcian.

Referred specimens: MPEF-PV 3305–3348 representing remains of at least three individuals (based on repeated elements) found at the same site. The specimens are similar sized (repeated humeri varying up to 15% in length) and include craniomandibular remains (premaxilla, maxilla, nasal, dentary, surangular), multiple isolated teeth, cervical, dorsal, and caudal vertebrae, and limb elements (see electronic supplementary material).

Diagnosis: basal eusauropod diagnosed by the following characters (autapomorphies indicated with *): pointed process on the anteroventral end of the premaxilla and anterodorsal end of the dentary*; anterior margin of the premaxilla without a marked step*; orbital margin of the frontal with a close V-shape pointed medially*, resulting in a short contribution to the orbit; supratemporal fenestra about as anteroposteriorly long as lateromedially wide*; strongly marked proatlantal facets on the laterodorsal margin of the foramen magnum; concave ventral margin of the distal portion of the cultriform process*; axis with the anterior process in the dorsal part of neural spine (convergent in Jobaria and Europasaurus); accessory lamina below the PCDL in middle cervical vertebrae*; EPRL present in middle cervical vertebrae. See electronic supplementary material for further details on diagnostic features.

     

 

D. Pol, J. Ramezani, K. Gomez, J. L. Carballido, A. Paulina Carabajal, O. W. M. Rauhut, I. H. Escapa and N. R. Cúneo. 2020. Extinction of Herbivorous Dinosaurs linked to Early Jurassic Global Warming Event. Proceedings of the Royal Society B: Biological Sciences. DOI: 10.1098/rspb.2020.2310

  twitter.com/PolDiego/status/1328856821755506689

 MEF.org.ar/blog/2020/11/18/estudian-como-el-calentamiento-global-ayudo-a-los-dinosaurios-gigantes 

  

        

Global warming triggered the evolution of giant dinosaurs

phys.org/news/2020-11-global-triggered-evolution-giant-dinosaurs.html