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[Ornithology • 2017] Myzomela irianawidodoae • A Colourful New Species of Myzomela Honeyeater from Rote Island in eastern Indonesia ---ScRaBBlE

Myzomela irianawidodoae Prawiradilaga, Baveja, Suparno, Ashari, Ng, Gwee, Verbelen & Rheindt, 2017  photo:   Philippe Verbelen  e-journ...

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Showing posts with label North America. Show all posts
Showing posts with label North America. Show all posts

Wednesday, March 20, 2019

[PaleoMammalogy • 2018] Allodesmus demerei • The Last of the Desmatophocid Seals: A New Species of Allodesmus from the upper Miocene of Washington, USA, and A Revision of the Taxonomy of Desmatophocidae ---ScRaBBlE


Allodesmus demerei 
Boessenecker & Churchill, 2018


Abstract
The family Desmatophocidae represents an early radiation of extinct pinnipeds that peaked in diversity during the middle Miocene. Although represented by abundant well-preserved fossils, the taxonomy and evolutionary relationships of this family remain poorly known. Late Miocene desmatophocids have been recorded, although none have been formally described, preventing a thorough appraisal of their decline and extinction. We report the discovery of a new species, Allodesmus demerei sp. nov., represented by a partial skeleton with cranium, mandibles, and axial skeleton, from the upper Miocene Montesano Formation of Washington, prompting reinterpretation of desmatophocid taxonomy, phylogeny, and extinction. Phylogenetic analysis (95 characters, 26 taxa) found strong support for monophyletic Desmatophocidae and Allodesmus. Desmatophocidae was found as sister to Phocidae with poor support. Allodesmus demerei was placed within the Allodesmus as the sister taxon to Allodesmus kernensis. The geochronologically young age (10.5–9.1 Mya) of Al. demerei establishes this species as the last of the desmatophocid seals. The middle Miocene peak in desmatophocid diversity coincides with the middle Miocene climatic optimum, suggesting that declining sea surface temperature played a role in their decline and extinction. Walruses diversified and increased in body size during the mid- to late Miocene as desmatophocids declined, suggesting some form of ecological displacement.








Robert W. Boessenecker and Morgan Churchill. 2018. The Last of the Desmatophocid Seals: A New Species of Allodesmus from the upper Miocene of Washington, USA, and a revision of the taxonomy of Desmatophocidae.  Zoological Journal of the Linnean Society. zlx098.  DOI:  10.1093/zoolinnean/zlx098 

Remains found in Grays Harbor lead to discovery of new species kxro.com/remains-found-grays-harbor-lead-discovery-new-species/


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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Bryophyta • 2018] Sphagnum incundum • A New Species in Sphagnum subg. Acutifolia (Sphagnaceae) from Boreal and Arctic Regions of North America ---ScRaBBlE


Sphagnum incundum  Flatberg & Hassel

in Kyrkjeeide, Hassel, Shaw, Shaw, Temsch & Flatberg, 2018.

Abstract
We describe Sphagnum incundum in Sphagnum subgenus Acutifolia (Sphagnaceae, Bryophyta). We used both molecular and morphological methods to describe the new species. Molecular relationships with closely related species were explored based on microsatellites and nuclear and plastid DNA sequences. The morphological description is based on qualitative examination of morphological characters and measurements of leaves and hyalocysts. Morphological characters are compared between closely related species. The results from Feulgen densitometry and microsatellite analysis show that S. incundum is gametophytically haploid. Molecular analyses show that it is a close relative to S. flavicomans, S. subfulvum and S. subnitens, but differs both genetically and in morphological key characters, justifying the description of Sphagnum incundum as a new species. The new peatmoss is found in North America along the western coast of Greenland, in Canada from Quebec and Northwest Territories, and Alaska (United States). The new species has a boreal to arctic distribution.

Keywords: Bryophytes, Sphagnaceae



FIGURE 8. Sphagnum incundum in field surface view.
A: The type collection including selected holotype and isotypes. Collected in Ivujivik, Quebec, Canada, in intermediate, slightly sloping arctic fen.
Photo by K. I. Flatberg, 4 July 2007. Flatberg 314-07 (TRH B-9718). 
B: Together with S. squarrosum, both with young sporophytes. From Inukjuak, Quebec, Canada, in topogenous, rich fen lawn in arctic mire.
Photo by K. I. Flatberg, 14 August 2007. Flatberg 451-07 (TRH B-9999). 

Sphagnum incundum Flatberg & Hassel sp. nov. 

 Diagnosis:— Sphagnum incundum is in macro-morphology recognized by slender shoots with predominantly brownorange to purple-red capitula and straight and non-recurved leaves on innermost capitulum branches on dry plants. In micro-morphology, it is foremost recognized by narrowly lingulate stem leaves with acute to acute-obtuse apices, strongly S-shaped stem leaf hyalocysts with common occurrence of faint fibrils in distal leaf-parts, and divergent branch leaf hyalocysts on distal end convex surfaces with pores usually occupying between 1/3 and 1/2 of cell width. The new species is gametophytic haploid and closely allied morphologically to S. flavicomans, S. subfulvum, and S. subnitens.

Etymology:— The specific epithet is derived from the Latin adjective incundus = pleasant, agreeable, delightful.

 Distribution:— West Greenland, Canada in Quebec, Nunavut and North West territories, and U.S.A in Alaska. Currently known from the northern boreal to middle arctic vegetation zone. 

Ecology:— Sphagnum incundum in arctic localities in West Greenland, and Nunavik, Quebec, occurs in arctic mires on shallow peat in intermediate and rich fens, partly forming small mats and low cushions on gently sloping, soligenous mire, partly growing in small patches on lawn and carpet mire. The most commonly associated sphagna in both regions were S. concinnum (Berggr.) Flatberg (2007: 88), S. squarrosum, S. teres and S. warnstorfii Russow (1886: 315). In the boreal Anchorage area, Alaska, it was found growing in a large fen mire on high lawn patches in topogenous, varyingly intermediate to rich fen vegetation, associated with S. papillosum Lind. (1872: 280), S. subfulvum and S. miyabeanum Warnstorf (1911: 321). In Bethel area, Alaska, it occurred scattered on intermediate fen lawns in tundra mire.


 Magni Olsen Kyrkjeeide, Kristian Hassel, Blanca Shaw, A. Jonathan Shaw, Eva M. Temsch and Kjell Ivar Flatberg. 2018. Sphagnum incundum A New Species in Sphagnum subg. Acutifolia (Sphagnaceae) from Boreal and Arctic Regions of North America. Phytotaxa. 333(1); 1–21. DOI:  10.11646/phytotaxa.333.1.1

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Paleontology • 2018] Kootenayscolex barbarensis • A New Burgess Shale Polychaete and the Origin of the Annelid Head Revisited ---ScRaBBlE


Kootenayscolex barbarensis
Nanglu & Caron, 2018 


Highlights: 
•An abundant Cambrian polychaete preserves exceptional morphological details
•The new species possesses a median antenna and large palps on the prostomium
•Neuropodial chaetae are present on the mouth-bearing peristomium
•A chaetigerous origin for the peristomial portion of the annelid head is proposed

Summary
Annelida is one of the most speciose (∼17,000 species) and ecologically successful phyla. Key to this success is their flexible body plan with metameric trunk segments and bipartite heads consisting of a prostomium bearing sensory structures and a peristomium containing the mouth. The flexibility of this body plan has traditionally proven problematic for reconstructing the evolutionary relationships within the Annelida. Although recent phylogenies have focused on resolving the interrelationships of the crown group, many questions remain regarding the early evolution of the annelid body plan itself, including the origin of the head. Here we describe an abundant and exceptionally well-preserved polychaete with traces of putative neural and vascular tissues for the first time in a fossilized annelid. Up to three centimeters in length, Kootenayscolex barbarensis gen. et sp. nov. is described based on more than 500 specimens from Marble Canyon and several specimens from the original Burgess Shale site (both in British Columbia, Canada). K. barbarensis possesses biramous parapodia along the trunk, bearing similar elongate and thin notochaetae and neurochaetae. A pair of large palps and one median antenna project from the anteriormost dorsal margin of the prostomium. The mouth-bearing peristomium bears neuropodial chaetae, a condition that is also inferred in Canadia and Burgessochaeta from the Burgess Shale, suggesting a chaetigorous origin for the peristomial portion of the head and a secondary loss of peristomial parapodia and chaetae in modern polychaetes.

Keywords: Annelida, polychaete, Burgess Shale, Cambrian Explosion, body plan, prostomium, peristomium, annelid head evolution, Marble Canyon


Life reconstruction of Kootenayscolex barbarensis.

Illustration: Danielle Dufault/Royal Ontario Museum  

Kootenayscolex barbarensis is part of a group of animals called annelids (or the 'ringed worms'). It had a pair of long sensory structures called palps on its head, with a small medial antenna between them (right). Its body was covered in fleshy appendages called parapodia which bear bristles called chaetae. These structures are used for movement.

 photo: Jean-Bernard Caron/Royal Ontario Museum


Karma Nanglu and Jean-Bernard Caron. 2018. A New Burgess Shale Polychaete and the Origin of the Annelid Head Revisited. Current Biology. 28(2); p319–326.e1.  DOI: 10.1016/j.cub.2017.12.019

New 508-million-year-old bristle worm species from British Columbia's Burgess Shale wiggles into evolutionary history  phy.so/435841146 via @physorg_com
Half Billion-Year-Old Fossil Clue to How Worms Evolved  on.natgeo.com/2n58ibF via @NatGeo

   

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Cnidaria • 2018] Revision of the Genus Adelogorgia Bayer, 1958 (Anthozoa: Octocorallia) with the Description of Three New Species ---ScRaBBlE


Adelogorgia osculabunda, A. hannibalis & A. adusta 
 Breedy & Guzman, 2018 


Abstract

The genus Adelogorgia is distinguished from other holaxonians in having conspicuously ornamented double-disc sclerites and leaf clubs in the coenenchyme, and non-mineralised axis cores. The two eastern Pacific species currently recognised as Adelogorgia are diagnosed and illustrated. Three new species for the genus are described from new localities and depth ranges. Analysis of external and internal characters, especially sclerite colours and sizes, and colony colour, shape and branching, allows separating the species. An identification key to the five species is provided, as well as a character table for comparisons. This study was based on newly collected specimens from 50 to 200 m deep, and re-examination of all historical material. We conclude that the genus comprises five valid species with a wider distribution than previously reported. This research is a contribution to the octocoral systematics and biodiversity from mesophotic and deep waters.

Keywords: Anthozoa, Adelogorgia, Alcyonacea, biodiversity, eastern Pacific, plexaurid, soft corals, taxonomy




Class Anthozoa Ehrenberg, 1834
Subclass Octocorallia Haeckel, 1866

Order Alcyonacea Lamouroux, 1816
Family Plexauridae Gray, 1859

Genus Adelogorgia Bayer, 1958
Adelogorgia Bayer, 1958: 46; Bayer 1978: 1026–1027; Harden 1979: 137.

Type species. Adelogorgia phyllosclera Bayer, 1958 by original designation Type locality. La Jolla, California. Diagnosis (modified from Bayer, 1958; 1978). Colonies bushy, fan-shaped or sparsely branched. Branching lateral, irregular, or dichotomous; with moderately thick coenenchyme; polyps fully retractile, communicating directly with the longitudinal canal system (gastrodermal canals, solenia); anthocodia with eight subtentacular points consisting of spinous rods, not forming a distinct collaret. Polyp mounds prominent, slightly raised or flat, without specific types of sclerites, but leaf clubs concentrated around polyp apertures. Outer coenenchyme with conspicuous double discs with expansions on one side having various degrees of ornamentation; tuberculate spindles and leaf clubs. Axial sheath containing less developed spindles, radiates and capstans. Axis with wide cross-chambered central core. Loculi between lamellae and central core without mineralised filaments. Colony colours white, lemon-yellow, pink, orange and various hues of red. Sclerites of the same colours and colourless.

Distribution. The species has been reported from La Jolla, California, USA; Galápagos Islands, Ecuador (Bayer 1958, 1978); Baja California, Mexico (Harden 1979); and recently found along Pacific coast of Costa Rica and off Pacific coast of Panamá. Reported from 30 to 300 m deep (Cairns et al. 2002).


Adelogorgia phyllosclera Bayer, 1958

Adelogorgia telones Bayer, 1978

FIGURE 8. Adelogorgia osculabunda sp. nov., MZUCR 2494 (OCT-0083) (holotype)
(A) colony; (B) detail of the branches; (C) sclerites. 

Adelogorgia osculabunda sp. nov. 

Habitat and Distribution. The species has been collected by bottom trawls from sandy or muddy-sand substrata. It was also obtained from fishing lines and nets from rocky shoals, where the colonies were ripped as bycatch or were entangled in the lines from 40 to 60 m deep. Adelogorgia osculabunda was commonly collected together with Leptogorgia regis Hickson, 1928, Muricea fruticosa Verrill, 1868, Muricea subtilis Breedy and Guzman, 2016 and two Psammogorgia species. The species was found at various localities in Costa Rica, from: off Salinas Bay and Santa Elena Bay to Cape Santa Elena, Guanacaste (northern Pacific); and Punta Mala, Puntarenas (central Pacific) that suggests a wide distribution of the species along the Pacific. In Panamá, Pearl Islands, the colonies were obtained by dredging at 80 m deep, which presently represents the deepest record.

Etymology. Named osculabunda, Latin adjective derived from osculumlittle mouthkiss. In Latin context, osculabunda is the one that covers with kisses, in allusion to the red prominent polyp-mounds that cover the branches. Remarks. This species is similar to A. hannibalis in the prominent polyp-mounds showing a little darker orange contrasting with the colony colour, but is not as evident as in A. osculabunda. Thinner colonies of A. osculabunda look similar to A. hannibalis, but in A. osculabunda, the polyp-mounds are closer and stiffer than in A. hannibalis. Additionally, sclerite analysis shows clear differences between the two species.

FIGURE 10. Adelogorgia hannibalis sp. nov., STRI 1206 (holotype)
(A) colony; (B) detail of the branches; (C) sclerites. 

Adelogorgia hannibalis sp. nov. 

Habitat and Distribution. The species was found on the Hannibal Bank, a coastal guyot-type seamount that rises from approximately 500 m to 45 m, located 50 km from the mainland (Cunningham et al. 2013). The seamount is relatively protected as part of the Coiba National Park and World Heritage. The species was found on rocky substrate with strong currents. It is only known from the type locality, Hannibal Bank, from 180 to 200 m deep.

Etymology. Named after the Hannibal Bank and the surveyor USS Hannibal that discovered and charted the bank for the first time, presumably in 1934. The name Hannibal evokes the Carthaginian general, considered one of the greatest military commanders in ancient history. In genitive: hannibalis (L) meaning ¨of Hannibal¨.


FIGURE 12. Adelogorgia adusta sp. nov., STRI-HH 1220 (holotype).
(A) colony; (B) detail of the branches; (C) sclerites. B, photograph by Sean Mattson. 

Adelogorgia adusta sp. nov. 

Habitat and Distribution. The species was found in the Hannibal Bank, on rocky substrates impacted by currents. Adelogorgia adusta is only known from the type locality Hannibal Bank, from 73 to 94 m deep.

Etymology. Named adusta, Latin adjective meaning burntscorchedcharred, in allusion to the burnt appearance that the colony takes after fixation. The word adustus, in Castellan language, adusto, was evoked in verse 62 of The Fable of Polifemo and Galatea (Spanish poet Luis de Góngora) referring to the son of the Pirineo (giant mount) who supposedly was put in flames


Odalisca Breedy and Hector M. Guzman. 2018. Revision of the Genus Adelogorgia Bayer, 1958 (Cnidaria: Anthozoa: Octocorallia) with the Description of Three New Species.  Zootaxa. 4369(3); 327–348.  DOI:  10.11646/zootaxa.4369.3.2

New Fractal-like Soft Coral Species Discovered in Panama and Costa Rica  bit.ly/2E8vCxg



  

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Paleontology • 2017] Borealopelta markmitchelli • An Exceptionally Preserved Three-Dimensional Armored Dinosaur Reveals Insights into Coloration and Cretaceous Predator-Prey Dynamics ---ScRaBBlE


Borealopelta markmitchelli 
Brown, Henderson, Vinther, Fletcher, Sistiaga, Herrera & Summons, 2017


Highlights
• A new armored dinosaur is described based on an exceptionally preserved specimen
• Abundant in situ osteoderms with keratinous sheaths and scales are preserved
• Reddish-brown coloration and crypsis in the form of countershading are indicated
• Crypsis indicates strong predation pressure on this large, heavily armored dinosaur


Summary
Predator-prey dynamics are an important evolutionary driver of escalating predation mode and efficiency, and commensurate responses of prey. Among these strategies, camouflage is important for visual concealment, with countershading the most universally observed. Extant terrestrial herbivores free of significant predation pressure, due to large size or isolation, do not exhibit countershading. Modern predator-prey dynamics may not be directly applicable to those of the Mesozoic due to the dominance of very large, visually oriented theropod dinosaurs. Despite thyreophoran dinosaurs’ possessing extensive dermal armor, some of the most extreme examples of anti-predator structures, little direct evidence of predation on these and other dinosaur megaherbivores has been documented. Here we describe a new, exquisitely three-dimensionally preserved nodosaurid ankylosaur, Borealopelta markmitchelli gen. et sp. nov., from the Early Cretaceous of Alberta, which preserves integumentary structures as organic layers, including continuous fields of epidermal scales and intact horn sheaths capping the body armor. We identify melanin in the organic residues through mass spectroscopic analyses and observe lighter pigmentation of the large parascapular spines, consistent with display, and a pattern of countershading across the body. With an estimated body mass exceeding 1,300 kg, B. markmitchelli was much larger than modern terrestrial mammals that either are countershaded or experience significant predation pressure as adults. Presence of countershading suggests predation pressure strong enough to select for concealment in this megaherbivore despite possession of massive dorsal and lateral armor, illustrating a significant dichotomy between Mesozoic predator-prey dynamics and those of modern terrestrial systems.

 Systematic Paleontology

Dinosauria Owen, 1842  
Ornithischia Seeley, 1888  

Ankylosauria Osborn, 1923  
Nodosauridae Marsh, 1890  

Borealopelta markmitchelli gen. et sp. nov. 

Etymology: The generic name Borealopelta is derived from “borealis” (Latin, “northern”) and “pelta” (Greek, “shield”), in reference to the northern locality and the preserved epidermal scales and dermal osteoderms. The specific epithet markmitchelli honors Mark Mitchell for his more than 7,000 hours of patient and skilled preparation of the holotype.


An illustration of Borealopelta markmitchelli. The study suggests that it displayed a camouflage effect known as counter-shading.
 Illustration: Julius Csotonyi/Courtesy of the Royal Tyrrell Museum of Palaeontology, Canada. 


 Illustration: Robert Nicholls 


 Illustration: Davide Bonadonna











Figure 1. Photographs of the Holotype of Borealopelta markmitchelli, TMP 2011.033.0001 Top: anterodorsolateral view; bottom: anterodorsal view. Scale bar, 10 cm. 




Holotype: The holotype is Royal Tyrrell Museum of Palaeontology (TMP) 2011.033.0001: an articulated specimen preserving the head, neck, most of the trunk and sacrum, a complete right and a partial left forelimb and manus, partial pes (Figure 1). In situ osteoderms and nearly complete soft tissue integument are preserved across dorsal and lateral surfaces of the axial skeleton, posterodorsal surface of forelimbs, and plantar surfaces of a manus and a pes. Specimen is preserved in multiple large blocks, including slabs and counter-slabs in the sacral region.

Locality and Horizon: Suncor Millennium Mine, Fort McMurray, Alberta, Canada. Wabiskaw Member, Clearwater Formation, Aptian stage. Detailed locality data are available at Royal Tyrrell Museum of Palaeontology.

Diagnosis: A nodosaurid ankylosaur characterized by the following autapomorphies (∗) and suite of characters [character/state]: cranial: dorsal skull ornamentation expressed as a large hexagonal dermal plate in frontoparietal region and multiple (>20) small dermal plates in frontonasal region∗; external nares excluded from view dorsally (shared with Pawpawsaurus) [16:1]; supraorbital ornamentation forming sharp lateral rim dorsal to orbits (shared with Gargoyleosaurus and Kunbarrasaurus) [38:2]; jugal (suborbital) horn triangular with pointed apex (shared with GastoniaGargoyleosaurus, and Polocanthus); jugal (suborbital) horn base longer than orbit length∗; osteoderms: cervical and thoracic osteoderms form continuous (abutting) transverse rows completely separated by continuous transverse rows of polygonal basement scales; parascapular spine is the largest osteoderm, recurved, and projects posterolaterally and horizontally (potentially shared with Sauropelta); osteoderm count for transverse rows: cervicals: C1-3, C2-3, C3-3, transition: TR-2, thoracic: T1-6∗; third and sixth transverse thoracic osteoderm rows expressed medially but pinch out laterally∗.

The new taxon can be further differentiated from Pawpawsaurus based on: dermal plate in frontonasal region (central dermal plates) flat; absence of ciliary osteoderm. Can be further differentiated from Sauropelta based on: parietals flat to slightly convex; cervical half ring has 4–6 osteoderms only; medial cervical osteoderms subequal, hexagonal, and bear prominent median ridge with posterior margin projecting beyond the basal footprint.





Figure 2: Schematic Line Drawing of TMP 2011.033.0001, the Holotype of Borealopelta markmitchelli, Illustrating Preservation of the Different Tissue Types (A) Schematic of complete specimen in dorsal view. (B and C) Skull in dorsal (B) and left lateral (C) views. (D) Close-up view of the neck, illustrating alternating cervical osteoderm bands (and preserved keratinous sheaths) and polygonal scales. (E) Close-up view of flank illustrating lateral thoracic osteoderms (with keratinous coverings) and polygonal scales. (F) Close-up view of sacral shield counterpart illustrating osteoderms and scales. (G) Close-up view of antebrachium including osteoderms and keratinous coverings. (D’–G’) Interpretive line drawings of the corresponding panels (D)–(G). Scale bars in (B)–(G), 10 cm.

Figure 3Time-Calibrated Strict Consensus Tree Showing Position of Borealopelta markmitchelli within Ankylosauria, with Representative Well-Preserved Ankylosaurs Shown Above Bottom: time-calibrated strict consensus tree illustrating position of Borealopelta markmitchelli within Ankylosauria scaled to Jurassic and Cretaceous stages. Top: line drawings of representative well-preserved ankylosaur specimens with in situ armor and/or skin. Scale bars, 1 m.
(A) Kunbarrasaurus, QM F18101. (B) Euoplocephalus, NHMUK 5161. (C) Sauropelta, AMNH 3035 and 3036 composite. (D) Borealopelta, TMP 2011.033.0001 (this study). (E) Edmontonia, AMNH 5665.

Figure 4:  Chart Illustrating the Loss of Countershading as Body Mass Increases in Terrestrial Mammal Herbivores Chart includes pooled data for artiodactyls, perissodactyls, and proboscideans divided into body-mass bins, showing relative proportion of species that exhibit countershading. The diagonally hatched area represents the mass above which significant predation of adults does not occur. Animals illustrated above chart are representative taxa within each mass bin; species names in italics at top indicate body masses of the largest carnivores.

The Making of a Most Extraordinary Fossil

The Making of a Most Extraordinary Fossil

Caleb M. Brown, Donald M. Henderson, Jakob Vinther, Ian Fletcher, Ainara Sistiaga, Jorsua Herrera and Roger E. Summons. 2017. An Exceptionally Preserved Three-Dimensional Armored Dinosaur Reveals Insights into Coloration and Cretaceous Predator-Prey Dynamics. Current Biology. DOI: 10.1016/j.cub.2017.06.071


Despite heavy armor, new dinosaur used camouflage to hide from predators  eurekalert.org/e/7ZWJ via @CellPressNews @EurekAlert

It's Official: Stunning Fossil Is a New Dinosaur Species  on.natgeo.com/2vx0wxD via @NatGeo
This Is the Best Dinosaur Fossil of Its Kind Ever Found on.natgeo.com/2r02aW7 via @NatGeo
Discover How This Dinosaur Became an Extraordinary Fossil  NationalGeographic.com/magazine/2017/06/making-of-a-dinosaur-fossil-nodosaur-illustrations

Heavily armoured dinosaur had ginger camouflage to deter predators – study  theguardian.com/science/2017/aug/03/heavily-armoured-nodosaur-ginger-camouflage-predators-borealopelta-markmitchelli


ติดอยู่ในกาลเวลา  ngthai.com/animals/1703 via  เนชันแนล จีโอกราฟฟิก (National Geographic) ฉบับภาษาไทย

  

  


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او
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