Fossil evidence reveals how plants responded to cooling during the Cretaceous-Paleogene transition

Abstract Background Around the Cretaceous-Paleogene (K-Pg) boundary, an obvious global cooling occurred, which resulted in dramatic changes in terrestrial ecosystems and the evolutionary trends of numerous organisms. However, how plant lineages responded to the cooling has remained unknown until now. Between ca. 70–60 Ma Mesocyparis McIver & Basinger (Cupressaceae), an extinct conifer genus, was distributed from eastern Asia to western North America and provides an excellent opportunity to solve this riddle. Results Here we report a new species, Mesocyparis sinica from the early Paleocene of Jiayin, Heilongjiang, northeastern China. By integrating lines of evidence from phylogeny and comparative morphology of Mesocyparis, we found that during ca.70–60 Ma, the size of seed cone of Mesocyparis more than doubled, probably driven by the cooling during the K-Pg transition, which might be an effective adaptation for seed dispersal by animals. More importantly, we discovered that the northern limit of this genus, as well as those of two other arboreal taxa Metasequoia Miki ex Hu et Cheng (gymnosperm) and Nordenskioldia Heer (angiosperm), migrated ca.4–5° southward in paleolatitude during this time interval. Conclusions Our results suggest that the cooling during the K-Pg transition may have been responsible for the increase in size of the seed cone of Mesocyparis and have driven the migration of plants southwards.

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Revision of Piceoerpeton Meszoely (Caudata: Scapherpetontidae) and description of a new species from the late Maastrichtian and ?early Paleocene of western North America

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.183.6.611 ◽

2012 ◽

Vol 183 (6) ◽

pp. 611-620 ◽

Cited By ~ 5

Author(s):

James D. Gardner

Keyword(s):

New Species ◽

North America ◽

Articular Surface ◽

Odontoid Process ◽

Ventral Surface ◽

Western North America ◽

Articular Surfaces ◽

The Family ◽

Early Paleocene ◽

A New Species

Abstract The scapherpetontid salamander Piceoerpeton is known from the latest Cretaceous to middle Paleogene of North America and was the last surviving member of that paedomorphic family. A suite of vertebral features differentiates Piceoerpeton from other scapherpetontids, including three atlantal features that are autapomorphic within the family: odontoid process reduced to an anteriorly short, nipple-like structure; ventral surface of odontoid process lacks an articular surface for contact with skull; and articular surfaces of anterior cotyles are deeply concave. Differences in inferred body size and vertebral structure permit the recognition of two congeners: P. willwoodense, a large-bodied species (estimated snout-vent length = 100 cm) from the late Paleocene of the Western Interior and early Eocene of the Canadian Arctic and the much smaller P. naylori new species from the late Maastrichtian and ?early Paleocene of Wyoming and Montana, USA. In terms of its older age, smaller size, and less derived vertebral features, P. naylori is potentially ancestral to P. willwoodense.

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Systematics of Hymenophyllum subgenus Mecodium (Hymenophyllaceae) in Taiwan

Systematic Botany ◽

10.1600/036364419x15710776741413 ◽

2019 ◽

Vol 44 (4) ◽

pp. 753-767

Author(s):

Tian-Chuan Hsu ◽

Yu-Fang Huang ◽

Yi-Shan Chao

Keyword(s):

Phylogenetic Relationships ◽

The Philippines ◽

Common Element ◽

Morphological Investigation ◽

Eastern Asia ◽

Type Specimens ◽

The Status ◽

Molecular Phylogenetic ◽

A New Species ◽

Independent Species

Abstract—Hymenophyllum subg. Mecodium, composed of the taxonomically notorious H. polyanthos and approximately 15 other closely related taxa, is a common element of filmy fern communities in the tropical and subtropical moist forests. In Taiwan, although only H. polyanthos and one or two closely related taxa were recognized in recent studies, considerable morphological variation has been observed among populations throughout the island. Thus, we conducted an extensive morphological investigation, as well as a molecular phylogenetic analysis, to clarify the specific diversity and phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan. Field and herbaria surveys helped in recognizing five morphs in Taiwan, mainly differentiated by the combination of certain traits, viz., the presence or absence of stipe wings, general frond size and shape, degree of laminar crispation, sori position, and involucre shape. The different morphs had diverse ecological preferences. The phylogenetic tree, inferred from the sequences of the plastid loci rbcL and rps4-trnS, demonstrated that Hymenophyllum subg. Mecodium materials in Taiwan comprise several well-supported lineages, mostly corresponding to the classification based on morphology. Comparing with the protologues and type specimens of 34 related scientific names, the five morphs are herein recognized as five independent species. A new species, Hymenophyllum exquisitum, is described here. Also, the status of H. paniculiflorum is reconfirmed and that of H. fujisanense, H. parallelocarpum, and H. punctisorum reinstated. Only H. exquisitum and H. parallelocarpum are endemic to Taiwan among all the species studied. In addition, the names Hymenophyllum blumeanum, H. integrum, H. microsorum, H. polyanthos, H. tenellum, and H. wrightii are now excluded from the regional flora, and several related taxa from China, Taiwan, and the Philippines are treated as synonyms. This study unravels the deep phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan and Eastern Asia.

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Tectono-Sedimentary Evolution of the Cenozoic Basins in the Eastern External Betic Zone (SE Spain)

Geosciences ◽

10.3390/geosciences10100394 ◽

2020 ◽

Vol 10 (10) ◽

pp. 394

Author(s):

Manuel Martín-Martín ◽

Francesco Guerrera ◽

Mario Tramontana

Keyword(s):

Strike Slip ◽

Alluvial Fan ◽

Tectonic Activity ◽

Time Interval ◽

Se Spain ◽

The Third ◽

Sedimentary Evolution ◽

Marine Sedimentation ◽

Geodynamic Processes ◽

Early Paleocene

Four main unconformities (1–4) were recognized in the sedimentary record of the Cenozoic basins of the eastern External Betic Zone (SE, Spain). They are located at different stratigraphic levels, as follows: (1) Cretaceous-Paleogene boundary, even if this unconformity was also recorded at the early Paleocene (Murcia sector) and early Eocene (Alicante sector), (2) Eocene-Oligocene boundary, quite synchronous, in the whole considered area, (3) early Burdigalian, quite synchronous (recognized in the Murcia sector) and (4) Middle Tortonian (recognized in Murcia and Alicante sectors). These unconformities correspond to stratigraphic gaps of different temporal extensions and with different controls (tectonic or eustatic), which allowed recognizing minor sedimentary cycles in the Paleocene–Miocene time span. The Cenozoic marine sedimentation started over the oldest unconformity (i.e., the principal one), above the Mesozoic marine deposits. Paleocene-Eocene sedimentation shows numerous tectofacies (such as: turbidites, slumps, olistostromes, mega-olistostromes and pillow-beds) interpreted as related to an early, blind and deep-seated tectonic activity, acting in the more internal subdomains of the External Betic Zone as a result of the geodynamic processes related to the evolution of the westernmost branch of the Tethys. The second unconformity resulted from an Oligocene to Aquitanian sedimentary evolution in the Murcia Sector from marine realms to continental environments. This last time interval is characterized as the previous one by a gentle tectonic activity. On the other hand, the Miocene sedimentation was totally controlled by the development of superficial thrusts and/or strike-slip faults zones, both related to the regional geodynamic evolutionary framework linked to the Mediterranean opening. These strike-slip faults zones created subsidence areas (pull-apart basin-type) and affected the sedimentation lying above the third unconformity. By contrast, the subsidence areas were bounded by structural highs affected by thrusts and folds. After the third unconformity, the Burdigalian-Serravallian sedimentation occurred mainly in shallow- to deep-water marine environments (Tap Fm). During the Late Miocene, after the fourth unconformity, the activation of the strike-slip faults zones caused a shallow marine environment sedimentation in the Murcia sector and a continental (lacustrine and fluvial) deposition in the Alicante sector represented the latter, resulting in alluvial fan deposits. Furthermore, the location of these fans changed over time according to the activation of faults responsible for the tectonic rising of Triassic salt deposits, which fed the fan themselves.

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A Review of Recently Discovered Remains of the Pleistocene Branchiopods (Anostraca, Notostraca) from NE Siberia and Arctic Canada

Water ◽

10.3390/w13030280 ◽

2021 ◽

Vol 13 (3) ◽

pp. 280

Author(s):

D. Christopher Rogers ◽

Anton A. Zharov ◽

Anna N. Neretina ◽

Svetlana A. Kuzmina ◽

Alexey A. Kotov

Keyword(s):

Western North America ◽

Temporary Wetlands ◽

Indicator Organisms ◽

Aquatic Habitats ◽

Eastern Asia ◽

Large Mammal ◽

Large Branchiopods ◽

North Eastern ◽

North Western ◽

Large Branchiopod

In this study, we examine, identify, and discuss fossil remains of large branchiopod crustaceans collected from six sites across the Beringian region (north-eastern Asia and north-western North America). Eggs and mandibles from Anostraca and Notostraca, as well as a notostracan telson fragment and a possible notostracan second maxilla, were collected from both paleosediment samples and also from large mammal hair. The remains of large branchiopods and other species that are limited to seasonally astatic aquatic habitats (temporary wetlands) could be useful indicator organisms of paleoecological conditions. Different recent large branchiopod species have very different ecological preferences, with each species limited to specific geochemical component tolerance ranges regarding various salinity, cation, and gypsum concentrations. Our purpose is to bring the potential usefulness of these common fossil organisms to the attention of paleoecologists.

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Eudaemonema webbi sp. nov. (Mammalia, Mixodectidae) from the late Paleocene of western Canada: the youngest known mixodectid

Canadian Journal of Earth Sciences ◽

10.1139/e10-074 ◽

2010 ◽

Vol 47 (12) ◽

pp. 1451-1462 ◽

Cited By ~ 6

Author(s):

Craig S. Scott

Keyword(s):

New Species ◽

North American ◽

Western Canada ◽

South Central ◽

Late Paleocene ◽

Early Paleocene ◽

Stratigraphic Ranges ◽

A New Species ◽

Stratigraphic Range

Mixodectidae (Mammalia, Archonta) are an unusual, poorly known family of dermopteran-like mammals that have been discovered at several North American localities of primarily early Paleocene age. Among the three or four recognized mixodectid genera, Eudaemonema Simpson is perhaps one of the least understood, being known from only a few localities of late Torrejonian and earliest Tiffanian age. This paper reports on a new species of Eudaemonema from the late Paleocene of Alberta, Canada, that significantly extends the geographic and stratigraphic ranges of the genus. Eudaemonema webbi sp. nov. is known from middle and late Tiffanian localities in central and south central Alberta, and it represents the youngest and northernmost species of Eudaemonema so far discovered. E. webbi differs from the genotypic species E. cuspidata in being larger and in having a suite of dental characters (e.g., molariform posterior premolars, enlarged molar protocone and hypocone, development of a second grinding platform on the lower molars) that suggests an increased emphasis on grinding during mastication. E. webbi possesses several dental features (e.g., broad, shelf-like molar paraconid–paracristid, lingually shifted molar hypoconulid) that resemble those of cynocephalids (Mammalia, Dermoptera), with these resemblances interpreted herein as convergent. The occurrence of E. webbi at Gao Mine extends the stratigraphic range of Eudaemonema into the late Tiffanian (Ti5) and represents the youngest known record of Mixodectidae.

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The new Belostoma fittkaui species group with supplemental descriptions of B. fittkaui De Carlo and B. sayagoi De Carlo

Zootaxa ◽

10.11646/zootaxa.4942.4.6 ◽

2021 ◽

Vol 4942 (4) ◽

pp. 583-591

Author(s):

FABIANO STEFANELLO

Keyword(s):

New Species ◽

South America ◽

Comparative Morphology ◽

Species Group ◽

Type Material ◽

Extreme Variation ◽

Species Groups ◽

A New Species ◽

Tropical South America

The giant water bug fauna from tropical South America remains poorly known. Three species of Belostoma Latreille (Belostoma fittkaui De Carlo, B. sayagoi De Carlo and B. hirsutum Roback & Nieser) have been cited only a few times in the literature. These three species are remarkable since they represent an extreme variation for the genus, with article II of the labium distinctly shorter than article III. Here, the synonymy of B. hirsutum with B. sayagoi is proposed based on examination of type material and additional specimens. Further, B. fittkaui and B. sayagoi are redescribed, including discussion about comparative morphology with congeners. A new species group is proposed for these species and a key to the Belostoma species groups is provided. Distribution records are also updated.

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A new euptychiine butterfly species from south Brazil and taxonomic rearrangements for Taydebis Freitas, 2013 and Hermeuptychia Forster, 1964 (Lepidoptera: Nymphalidae: Satyrinae)

Zootaxa ◽

10.11646/zootaxa.5023.4.5 ◽

2021 ◽

Vol 5023 (4) ◽

pp. 555-570

Author(s):

THAMARA ZACCA ◽

MIRNA M. CASAGRANDE ◽

OLAF H. H. MIELKE ◽

BLANCA HUERTAS ◽

ANDRÉ V. L. FREITAS ◽

...

Keyword(s):

New Species ◽

Species Distributions ◽

Comparative Morphology ◽

Junior Synonym ◽

Butterfly Species ◽

Additional Information ◽

A New Species ◽

South Brazil

A new species of Taydebis Freitas, 2003 from south Brazil is described using comparative morphology and species distributions. Also, based on morphology, we transfer Neonympha melobosis Capronnier, 1874 (formerly placed in Paryphthimoides Forster, 1964) to Taydebis, and recognize Euptychia peculiaris Butler, 1874 as its junior synonym (syn. nov.). Furthermore, the monotypic Prenda Freitas & Mielke, 2011 is herein treated as junior synonym of Taydebis based on morphology, molecular and ecological evidence. Species of Taydebis are endemic and restricted to south Brazil, and now comprises three species: Taydebis guria Zacca, Casagrande & Mielke sp. nov., T. melobosis comb. nov. and T. clarissa Freitas & Mielke comb. nov. To continue clarifying Euptychiina taxonomy, Euptychia undulata Butler, 1867 (also formerly placed in Paryphthimoides) is transferred to Hermeuptychia Forster, 1964, and we provide additional information on its taxonomy, morphology, and distribution. Diagnoses, illustrations, and distributional maps are provided for all taxa except T. clarissa comb. nov.

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A New Species of Pineus (Homoptera: Adelgidae) on Abies

The Canadian Entomologist ◽

10.4039/ent96522-3 ◽

1964 ◽

Vol 96 (3) ◽

pp. 522-528 ◽

Cited By ~ 5

Author(s):

G. R. Underwood ◽

R. E. Balch

Keyword(s):

New Species ◽

North America ◽

Coastal Region ◽

Western North America ◽

Abies Amabilis ◽

A New Species

AbstractA new anholocyclic species from the coastal region of western North America on Abies amabilis (Dougl.) Forbes and A. grandis (Dougl.) Lindl. is described. This is the first species of Pineus found on true firs.

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Adocus Kohaku, A New Species of Aquatic Turtle (Testudines: Cryptodira: Adocidae) from the Late Cretaceous of Kuji, Iwate Prefecture, Northeast Japan, with Special References to the Geological Age of the Tamagawa Formation (Kuji Group) LSID urn:lsid:zoobank.org:act:61376EEE-A386-416E-98AE-FF64FE2597A2

International Journal of Paleobiology & Paleontology ◽

10.23880/ijpbp-16000122 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Ren Hirayama

Keyword(s):

New Species ◽

Late Cretaceous ◽

Morphological Diversity ◽

Eastern Asia ◽

Geological Age ◽

Iwate Prefecture ◽

A New Species

A nearly complete shell of the genus Adocus (Adocidae; Pan-Trionychia; Cryptodira; Testudines) was collected from the late Cretaceous (Turonian) Tamagawa Formation of Kuji Group at Kuji City, Iwate Prefecture, northeast Japan. This turtle shows unique features such as the loss of cervical scute, extreme expansion of marginal scutes overlying costal plates, and exclusion of the humeral- pectoral sulcus from entoplastron. Thus, A. kohaku is erected as a new species. As A. kohaku shows most derived position of A. kohaku within this genus, morphological diversity of the genus Adocus seems to have occurred rather early in its evolution in Eastern Asia.

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Cranial anatomy of Allosaurus jimmadseni, a new species from the lower part of the Morrison Formation (Upper Jurassic) of Western North America

PeerJ ◽

10.7717/peerj.7803 ◽

2020 ◽

Vol 8 ◽

pp. e7803 ◽

Cited By ~ 5

Author(s):

Daniel J. Chure ◽

Mark A. Loewen

Keyword(s):

New Species ◽

North America ◽

Phylogenetic Analyses ◽

Upper Jurassic ◽

Morrison Formation ◽

Ventral Margin ◽

Western North America ◽

Theropod Dinosaur ◽

Theropod Dinosaurs ◽

A New Species

Allosaurus is one of the best known theropod dinosaurs from the Jurassic and a crucial taxon in phylogenetic analyses. On the basis of an in-depth, firsthand study of the bulk of Allosaurus specimens housed in North American institutions, we describe here a new theropod dinosaur from the Upper Jurassic Morrison Formation of Western North America, Allosaurus jimmadseni sp. nov., based upon a remarkably complete articulated skeleton and skull and a second specimen with an articulated skull and associated skeleton. The present study also assigns several other specimens to this new species, Allosaurus jimmadseni, which is characterized by a number of autapomorphies present on the dermal skull roof and additional characters present in the postcrania. In particular, whereas the ventral margin of the jugal of Allosaurus fragilis has pronounced sigmoidal convexity, the ventral margin is virtually straight in Allosaurus jimmadseni. The paired nasals of Allosaurus jimmadseni possess bilateral, blade-like crests along the lateral margin, forming a pronounced nasolacrimal crest that is absent in Allosaurus fragilis.

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