Evidence of Wild Fires From Cisuralian Permian China

First report of Cisuralian (early Permian) charcoal layers within a coal bed from Baode, North China with reference to global wildfire distribution

Authors:

Yan et al

Abstract:

Fossil charcoal is reported for the first time from a Cisuralian coal bed of the Shanxi Formation in the Qiaotou Section, Baode, Shanxi, North China. Based on anatomical characteristics, these charcoal fragments consist of coniferous or cordaitalean xylem, unidentified primary xylem and cordaitalean and possible fern leaves. These charcoal fragments represent the evidence of palaeowildfire taking place in tropical peat swamps during the Cisuralian in Cathaysia. The palaeowildfire is most likely to be a surface fire and burning litter and shrubby vegetation. Fire frequency for this early Permian peat swamp might have been on the order of 176–(294–588)–1429 years, close to modern values. Compared with modern analogues, the North China Block during the Cisuralian was probably wet in general but could be occasionally seasonally dry for short time intervals. Previous charcoal and inertinite records moreover indicate that palaeowildfires were globally common during the Cisuralian. Overall, more wildfire evidence was found in the Artinskian–Kungurian than the Asselian-Sakmarian (except in the Euramerican Realm), probably due to more suitable regional climate, vegetation to fuel fires and taphonomic circumstances.

A New Cisuralian Permian Fauna From Tropical Gondwana

New Permian fauna from tropical Gondwana

Authors:

Cisneros et al

Abstract:

Terrestrial vertebrates are first known to colonize high-latitude regions during the middle Permian (Guadalupian) about 270 million years ago, following the Pennsylvanian Gondwanan continental glaciation. However, despite over 150 years of study in these areas, the biogeographic origins of these rich communities of land-dwelling vertebrates remain obscure. Here we report on a new early Permian continental tetrapod fauna from South America in tropical Western Gondwana that sheds new light on patterns of tetrapod distribution. Northeastern Brazil hosted an extensive lacustrine system inhabited by a unique community of temnospondyl amphibians and reptiles that considerably expand the known temporal and geographic ranges of key subgroups. Our findings demonstrate that tetrapod groups common in later Permian and Triassic temperate communities were already present in tropical Gondwana by the early Permian (Cisuralian). This new fauna constitutes a new biogeographic province with North American affinities and clearly demonstrates that tetrapod dispersal into Gondwana was already underway at the beginning of the Permian.

pop sci write up.

A key for Understanding Cisuralian Permian Tetrapod Ichnofaunas

The Gerola Valley site (Orobic Basin, Northern Italy): A key for understanding late Early Permian tetrapod ichnofaunas

Authors:

Marchetti et al

Abstract:

A taxonomic study has been carried out on the historical Gerola Valley locality (Pizzo del Diavolo formation, late Cisuralian), which represents one of the best tetrapod ichnosites of the whole Southern Alps (North Italy). With respect to previous studies, the ichnoassociation is now enlarged and lists the following taxa: Amphisauropus, Dromopus, Erpetopus, Hyloidichnus, Limnopus, Varanopus. The optimal preservation of the material, which in some cases shows even traces of the skin, allowed the recognition of a new morphotype of Varanopus. The invertebrate ichnoassociation is newly described and is representative of impoverished Scoyenia and Mermia ichnofacies. A detailed facies analysis of the uppermost arenitic-pelitic lithofacies of the Pizzo del Diavolo formation, which revealed the most abundant fossil content (Locality 1) and of two new localities (pelitic facies, Localities 2, 3) shows a transition from shallow lacustrine to floodplain and alluvial fan environments under a generally dry climate. Besides the taxonomic revision of vertebrate tracks, the final aims of our study are: i) the depositional, palaeoenvironmental and climatic reconstruction of this sector of the Orobic Basin through an integration of palaeontological data and facies analysis; and ii) the regional correlation of this key stratigraphic succession with other coeval ichnofaunas in Pangaea.

Alierasaurus ronchii: a new Giant Caseid Synapsid From Cisuralian Permian Sardinia

Alierasaurus ronchii, gen. et sp. nov., a caseid from the Permian of Sardinia, Italy

Authors:

Romano et al

Abstract:

A giant caseid, Alierasaurus ronchii, gen. et sp. nov., is herein described, based on a partial postcranial skeleton collected from the Permian Cala del Vino Formation (Alghero, Nurra, northwest Sardinia). Despite the highly conservative morphology of ribs and vertebral material, typical of caseids, the very well-preserved foot elements show highly autapomorphic features, warranting assignment of the specimen to a new genus. In particular, the fourth metatarsal is not short and massive, as in other large caseids, and shows a distinct axial region. Finally, the claw-shaped ungual phalanges are autapomorphic in being proportionately very short, with a strong double ventral flexor tubercle positioned very close to the proximal phalangeal rim, and a distal end that is not spatulate, but rather subtriangular in transverse section. Principal component and reduced major axis slope analyses, performed on 10 caseid specimens, suggest that the observed changes in overall shape of metatarsal IV were mainly linked to the enormous body size reached by the Sardinian specimen.

How Many Dimetrodon Species Are Present in the Artinskian Permian Briar Creek Bonebed

Long bone histology indicates sympatric species of Dimetrodon (Lower Permian, Sphenacodontidae)

Authors:

Christen D. Shelton, P. Martin Sander, Koen Stein and Herman Winkelhorst

Abstract:

The Briar Creek Bonebed (Artinskian, Nocona Formation) in Archer County is one of the richest sources of Dimetrodon bones in the Lower Permian of Texas, USA. Based on size, a small (D. natalis), an intermediate (D. booneorum), and a large species (D. limbatus) have been described from this locality. It has been proposed that these traditionally recognised species represent an ontogenetic series of only one species. However, the ontogenetic series hypothesis is inconsistent with the late ontogenetic state of the small bones, as suggested by their osteology and degree of ossification. Histological analysis of newly excavated material from the Briar Creek Bonebed has resolved some of the discretion between these two competing hypothesis, confirming the coexistence of a small (D. natalis) with at least one larger Dimetrodon species. An external fundamental system is present in the largest sampled long bones identified as D. natalis. The histology of D. natalis postcrania is described as incipient fibro lamellar bone. This tissue is a combination of parallel-fibred and woven-fibred bone that is highly vascularised by incipient primary osteons. The species status of D. booneorum and D. limbatus remain unresolved.

Were Paleozoic Cycads Preadapted to Growing in Groves?

The ancient cycad lineage has been around since before the age of the dinosaurs. More recently, cycads also co-existed with large herbivorous mammals, such as the ice age megafauna that only went extinct a few tens of thousands of years ago. Cycads that are living today have large, heavy seeds with a fleshy outer coating that suggests they rely on large bodied fruit-eating animals to disperse their seeds. Yet there is little evidence that they are eaten and dispersed by today's larger-bodied animals, such as emus or elephants. If these plants are adapted for dispersal by a set of animals that has been missing from Earth's fauna for tens of thousands of years, then how can they still be around today? A new study proposes that the clumped dispersal mechanism these ancient plants most likely relied upon still serves them well today.

Fossil cycads are recorded from 280 million years ago around the time coniferous forests first arose. The ecological distribution pattern of many living cycads today suggests they have limited and ineffectual seed dispersal. For example, Macrozamia miquelii, a cycad endemic to Australia, is found in highly clumped, dense, numbers, where it dominates the understory. Moreover, large areas of seemingly suitable habitat often separate populations from each other. These patterns suggest that few to none of the seeds are being dispersed large distances away from parent plants, one of the long-standing tenets of the advantages of seed dispersal.

French Lagerstätte Full of Discosauriscus

A new vertebrate Lagerstätte from the Lower Permian of France (Franchesse, Massif Central): palaeoenvironmental implications for the Bourbon-l'Archambault basin

Authors:

1. J.-Sébastien Steyer (a)

2. Sophie Sanchez (a,b)

3. Pierre J. Debriette (c)

4. Andrea M.F. Valli (d)

5. François Escuille (e)

6. Burkhard Pohl (e)

7. Roger-Paul Dechambre (f)

8. Renaud Vacant (a)

9. Christopher Spence (g)

10. Gaël de Ploëg (h)

Affiliations:

a. UMR 7207 CNRS, Centre de Recherche Paléobiodiversité et Paléoenvironnements, Département Histoire de la Terre, Muséum national d'Histoire naturelle, CP38, 8 rue Buffon, 75005 Paris, France

b. Subdepartment of Animal Evolution and Development, Department of Physiology and Developmental Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden

c. Le Champ Bernard, 03210 Gipcy, France

d. 78 Rue du Pont Ginguet, 03000 Moulins-sur-Allier, France

e. Eldonia Society, 9 Avenue des Portes Occitanes, 03800 Gannat, France

f. 13 Boulevard Saint-Marcel, 75013 Paris, France

g. 84 rue Oberkampf, 75011 Paris, France

h. Centre Permanent d'Initiatives pour l'Environnement, Ferme du Châteaux d'Aramont, 1 rue St Pierre, 60410 Verberie, France

Abstract:

A new vertebrate locality from the Lower Permian (Cisuralian) of the Bourbon-l'Archambault basin (Massif Central, France) is reported and its associated flora and fauna preliminarily described. This locality corresponds to a mass mortality assemblage deposited in an aquatic environment. Interestingly, it has yielded hundreds of exceptionally well preserved seymouriamorph specimens, all referred to Discosauriscus austriacus. This exquisite assemblage corresponds to the first seymouriamorph Lagerstätte and the first record of D. austriacus outside the Boskovice basin in Czechia. It enlarges the geographical distribution of the species during the Early Permian, and has new palaeoenvironmental implications regarding the Palaeozoic Bourbon-l'Archambault basin.