The systematic relationships and biogeographic history of ornithischian dinosaurs

The systematic relationships of taxa traditionally referred to as ‘basal ornithopods’ or ‘hypsilophodontids’ remain poorly resolved since it was discovered that these taxa are not a monophyletic group, but rather a paraphyletic set of neornithischian taxa. Thus, even as the known diversity of these taxa has dramatically increased over the past two decades, our knowledge of their placement relative to each other and the major ornithischian subclades remained incomplete. This study employs the largest phylogenetic dataset yet compiled to assess basal ornithischian relationships (255 characters for 65 species level terminal taxa). The resulting strict consensus tree is the most well-resolved, stratigraphically consistent hypothesis of basal ornithischian relationships yet hypothesized. The only non-iguanodontian ornithopod (=basal ornithopod) recovered in this analysis isHypsilophodon foxii. The majority of former ‘hypsilophodontid’ taxa are recovered within a single clade (Parksosauridae) that is situated as the sister-taxon to Cerapoda. The Parksosauridae is divided between two subclades, the Orodrominae and the Thescelosaurinae. This study does not recover a clade consisting of the Asian taxaChangchunsaurus,Haya, andJeholosaurus(=Jeholosauridae). Rather, the former two taxa are recovered as basal members of Thescelosaurinae, while the latter taxon is recovered in a clade withYueosaurusnear the base of Neornithischia.The endemic South American clade Elasmaria is recovered within the Thescelosaurinae as the sister taxon toThescelosaurus. This study supports the origination of Dinosauria and the early diversification of Ornithischia within Gondwana. Neornithischia first arose in Africa by the Early Jurassic before dispersing to Asia before the late Middle Jurassic, where much of the diversification among non-cerapodan neornithischians occurred. Under the simplest scenario the Parksosauridae originated in North America, with at least two later dispersals to Asia and one to South America. However, when ghost lineages are considered, an alternate dispersal hypothesis has thescelosaurines dispersing from Asia into South America (via North America) during the Early Cretaceous, then back into North America in the latest Cretaceous. The latter hypothesis may explain the dominance of orodromine taxa prior to the Maastrichtian in North America and the sudden appearance and wide distribution of thescelosaurines in North America beginning in the early Maastrichtian. While the diversity of parksosaurids has greatly increased over the last fifteen years, a ghost lineage of over 40 myr is present between the base of Parksosauridae and Cerapoda, indicating that much of the early history and diversity of this clade is yet to be discovered. This new phylogenetic hypothesis provides a comprehensive framework for testing further hypotheses regarding evolutionary patterns and processes within Ornithischia.

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Amazonia as the Origin and Diversification Area of Didelphidae (Mammalia: Metatheria), and a Review of the Fossil Record of the Clade

Journal of Mammalian Evolution ◽

10.1007/s10914-021-09548-7 ◽

2021 ◽

Author(s):

Mariela C. Castro ◽

Murilo J. Dahur ◽

Gabriel S. Ferreira

Keyword(s):

South America ◽

Amazon Basin ◽

Parametric Models ◽

Isthmus Of Panama ◽

Biogeographic History ◽

Early Diversification ◽

Northern Portion ◽

History Of ◽

Environmental Events ◽

Fossil Records

AbstractDidelphidae is the largest New World radiation of marsupials, and is mostly represented by arboreal, small- to medium-sized taxa that inhabit tropical and/or subtropical forests. The group originated and remained isolated in South America for millions of years, until the formation of the Isthmus of Panama. In this study, we present the first reconstruction of the biogeographic history of Didelphidae including all major clades, based on parametric models and stratified analyses over time. We also compiled all the pre-Quaternary fossil records of the group, and contrasted these data to our biogeographic inferences, as well as to major environmental events that occurred in the South American Cenozoic. Our results indicate the relevance of Amazonia in the early diversification of Didelphidae, including the divergence of the major clades traditionally ranked as subfamilies and tribes. Cladogeneses in other areas started in the late Miocene, an interval of intense shifts, especially in the northern portion of Andes and Amazon Basin. Occupation of other areas continued through the Pliocene, but few were only colonized in Quaternary times. The comparison between the biogeographic inference and the fossil records highlights some further steps towards better understanding the spatiotemporal evolution of the clade. Finally, our results stress that the early history of didelphids is obscured by the lack of Paleogene fossils, which are still to be unearthed from low-latitude deposits of South America.

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Evolution of andrenine bees reveals a long and complex history of faunal interchanges between the Americas during the Mesozoic and Cenozoic

10.1101/2021.08.05.455338 ◽

2021 ◽

Author(s):

Kelli S Ramos ◽

Aline C Martins ◽

Gabriel A R Melo

Keyword(s):

North America ◽

South America ◽

Time Window ◽

Distributional Pattern ◽

Long Distance ◽

Early Diversification ◽

Palearctic Region ◽

Long Time ◽

The Times ◽

Dated Phylogeny

Bees are presumed to have arisen in the early to mid-Cretaceous coincident with the fragmentation of the southern continents and concurrently with the early diversification of the flowering plants. Among the main groups of bees, Andreninae sensu lato comprise about 3000 species widely distributed with greatest and disjunct diversity in arid areas of North America, South America, and the Palearctic region. Here, we present the first comprehensive dated phylogeny and historical biogeographic analysis for andrenine bees, including representatives of all currently recognized tribes. Our analyses rely on a dataset of 106 taxa and 7952 aligned nucleotide positions from one mitochondrial and six nuclear loci. Andreninae is strongly supported as a monophyletic group and the recovered phylogeny corroborates the commonly recognized clades for the group. Thus, we propose a revised tribal classification that is congruent with our phylogenetic results. The time-calibrated phylogeny and ancestral range reconstructions of Andreninae reveal a fascinating evolutionary history with Gondwana patterns that are unlike those observed in other subfamilies of bees. Andreninae arose in South America during the Late Cretaceous around 90 Million years ago (Ma) and the origin of tribes occurred through a relatively long time-window from this age to the Miocene. The early evolution of the main lineages took place in South America until the beginning of Paleocene with North American fauna origin from it and Palearctic from North America as results of multiple lineage interchanges between these areas by long-distance dispersal or hopping through landmass chains. Overall, our analyses provide strong evidence of amphitropical distributional pattern currently observed in Andreninae in the American continent as result at least three periods of possible land connections between the two American landmasses, much prior to the Panama Isthmus closure. The andrenine lineages reached the Palearctic region through four dispersal events from North America during the Eocene, late Oligocene and early Miocene, most probably via the Thulean Bridge. The few lineages with Afrotropical distribution likely originated from a Palearctic ancestral in the Miocene around 10 Ma when these regions were contiguous, and the Sahara Desert was mostly vegetated making feasible the passage by several organisms. Incursions of andrenine bees to North America and then onto the Old World are chronological congruent with distinct periods when open-vegetation habitats were available for trans-continental dispersal and at the times when aridification and temperature decline offered favorable circumstances for bee diversification.

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Phylogeny, biogeography and diversification patterns of side-necked turtles (Testudines: Pleurodira)

Royal Society Open Science ◽

10.1098/rsos.171773 ◽

2018 ◽

Vol 5 (3) ◽

pp. 171773 ◽

Cited By ~ 21

Author(s):

Gabriel S. Ferreira ◽

Mario Bronzati ◽

Max C. Langer ◽

Juliana Sterli

Keyword(s):

North America ◽

South America ◽

Evolutionary History ◽

Mass Extinctions ◽

Phylogenetic Hypothesis ◽

Widespread Distribution ◽

The Past ◽

Biogeographic History ◽

Dispersal Events ◽

Freshwater Environments

Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa–Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicariance would have shaped the current geographical distribution and, in the second, extinctions constrained a previously widespread distribution. Here, we aim to reconstruct pleurodiran biogeographic history and diversification patterns based on a new phylogenetic hypothesis recovered from the analysis of the largest morphological dataset yet compiled for the lineage, testing which biogeographical process prevailed during its evolutionary history. The resulting topology generally agrees with previous hypotheses of the group and shows that most diversification shifts were related to the exploration of new niches, e.g. littoral or marine radiations. In addition, as other turtles, pleurodires do not seem to have been much affected by either the Cretaceous–Palaeogene or the Eocene–Oligocene mass extinctions. The biogeographic analyses highlight the predominance of both anagenetic and cladogenetic dispersal events and support the importance of transoceanic dispersals as a more common driver of area changes than previously thought, agreeing with previous studies with other non-turtle lineages.

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Comparative Analysis of Genetic and Morphological Variation within the Platanthera hyperborea Complex (Orchidaceae)

Systematic Botany ◽

10.1600/036364420x16033962925303 ◽

2020 ◽

Vol 45 (4) ◽

pp. 767-778

Author(s):

Eranga Wettewa ◽

Nick Bailey ◽

Lisa E. Wallace

Keyword(s):

North America ◽

Diploid Species ◽

Morphological Characters ◽

Evolutionary Patterns ◽

Founding Population ◽

Multiple Origins ◽

Geographic Structure ◽

Species Complexes ◽

Nuclear Its ◽

Cryptic Taxa

Abstract—Species complexes present considerable problems for a working taxonomy due to the presence of intraspecific variation, hybridization, polyploidy, and phenotypic plasticity. Understanding evolutionary patterns using molecular markers can allow for a more thorough assessment of evolutionary lineages than traditional morphological markers. In this study, we evaluated genetic diversity and phylogenetic patterns among taxa of the Platanthera hyperborea (Orchidaceae) complex, which includes diploid (Platanthera aquilonis) and polyploid (Platanthera hyperborea, P. huronensis, and P. convallariifolia) taxa spanning North America, Greenland, Iceland, and Asia. We found that three floral morphological characters overlap among the polyploid taxa, but the diploid species has smaller flowers. DNA sequence variation in a plastid (rpL16 intron) and a nuclear (ITS) marker indicated that at least three diploid species have contributed to the genomes of the polyploid taxa, suggesting all are of allopolyploid origin. Platanthera convallariifolia is most like P. dilatata and P. stricta, whereas P. huronensis and P. hyperborea appear to have originated from crosses of P. dilatata and P. aquilonis. Platanthera huronensis, which is found across North America, has multiple origins and reciprocal maternal parentage from the diploid species. By contrast, P. hyperborea, restricted to Greenland and Iceland, appears to have originated from a small founding population of hybrids in which P. dilatata was the maternal parent. Geographic structure was found among polyploid forms in North America. The area of Manitoba, Canada appears to be a contact zone among geographically diverse forms from eastern and western North America. Given the geographic and genetic variation found, we recommend continued recognition of four green-flowered species within this complex, but caution that there may be additional cryptic taxa within North America.

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Effects of insecticides on adults and eggs of Drosophila suzukii (Diptera, Drosophilidae)

Revista Colombiana de Entomología ◽

10.25100/socolen.v43i2.5945 ◽

2017 ◽

Vol 43 (2) ◽

pp. 208 ◽

Cited By ~ 9

Author(s):

Daniele Cristine Hoffmann Schlesener ◽

Jutiane Wollmann ◽

Juliano De Bastos Pazini ◽

Anderson Dionei Grützmacher ◽

Flávio Roberto Mello Garcia

Keyword(s):

North America ◽

South America ◽

Chemical Control ◽

Stone Fruits ◽

Drosophila Suzukii ◽

Ovicidal Effect ◽

Mere Presence ◽

South Of Brazil ◽

Different Cultures ◽

First Time

Drosophila suzukii (Diptera, Drosophilidae) is an exotic species, endemic to Asia and currently a pest to small and stone fruits in several countries of North America and Europe. It was detected in 2013 for the first time in South America, in the south of Brazil. Unlike most drosophilids, this species deserves special attention, because the females are capable of oviposit inside healthy fruits, rendering their sale and export prohibited. Despite the confirmed existence of this species in different states of Brazil, this insect is yet been to be given the pest status. Nevertheless, the mere presence of this species is enough to cause concern to producers of small fruits and to justify further investigation for it’s control, especially chemical control for a possible change in status. Therefore, the goal of this work was to evaluate, in laboratory, mortality of D. suzukii adults and ovicidal effect when exposed to different insecticides registered for species of the Tephritidae and Agromyzidae families in different cultures. The insecticides deltamethrin, dimethoate, spinosad, fenitrothion, phosmet, malathion, methidathion, and zeta-cypermethrin resulted in mortality to 100 % of the subjects three days after the treatment (DAT). Regarding the effects over eggs, it was established that the insecticides fenitrothion, malathion, and methidathion deemed 100 % of the eggs not viable, followed by phosmet and diflubenzuron, which also caused elevated reduction in the eclosion of larvae two DAT.

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An outer shelf shelly fauna from Cambrian Series 2 (Stage 4) of North Greenland (Laurentia)

Journal of Paleontology ◽

10.1017/jpa.2020.112 ◽

2021 ◽

Vol 95 (S83) ◽

pp. 1-41

Author(s):

John S. Peel

Keyword(s):

New York ◽

New Species ◽

North America ◽

World Wide ◽

Wide Distribution ◽

East Greenland ◽

North East ◽

Small Shelly Fossils ◽

Stage 4 ◽

North Greenland

AbstractAn assemblage of 50 species of small shelly fossils is described from Cambrian Series 2 (Stage 4) strata in North Greenland, the present day northernmost part of the paleocontinent of Laurentia. The fossils are derived from the basal member of the Aftenstjernesø Formation at Navarana Fjord, northern Lauge Koch Land, a condensed unit that accumulated in a sediment-starved outer ramp setting in the transarctic Franklinian Basin, on the Innuitian margin of Laurentia. Most other small shelly fossil assemblages of similar age and composition from North America are described from the Iapetan margin of Laurentia, from North-East Greenland south to Pennsylvania. Trilobites are uncommon, but include Serrodiscus. The Australian bradoriid Spinospitella is represented by a complete shield. Obolella crassa is the only common brachiopod. Hyoliths, including Cassitella, Conotheca, Neogloborilus, and Triplicatella, are abundant and diverse, but most are represented just by opercula. Sclerites interpreted as stem-group aculiferans (sachitids) are conspicuous, including Qaleruaqia, the oldest described paleoloricate, Ocruranus?, Inughuitoconus n. gen., and Hippopharangites. Helcionelloid mollusks are diverse, but not common; they are associated with numerous specimens of the bivalve Pojetaia runnegari. The fauna compares best with that of the upper Bastion Formation of North-East Greenland, the Forteau Formation of western Newfoundland, and the Browns Pond Formation of New York, but several taxa have a world-wide distribution. Many specimens are encrusted with crystals of authigenic albite. New species: Anabarella? navaranae, Stenotheca? higginsi, Figurina? polaris, Hippopharangites groenlandicus, Inughuitoconus borealis, and Ocruranus? kangerluk.UUID: http://zoobank.org/160a17b1-3166-4fcf-9849-a3cabd1e04a3

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BIOSYSTEMATIC STUDIES ON XANTHIUM: TAXONOMIC APPRAISAL AND ECOLOGICAL STATUS

Canadian Journal of Botany ◽

10.1139/b59-016 ◽

1959 ◽

Vol 37 (2) ◽

pp. 173-208 ◽

Cited By ~ 66

Author(s):

Doris Löve ◽

Pierre Dansereau

Keyword(s):

North America ◽

South America ◽

Ecological Status ◽

Distinct Species ◽

Eastern North America ◽

Flowering Response ◽

Short Day ◽

Stable Species ◽

Enormous Variation

The following paper is an evaluation of the taxonomic and ecological status of the genus Xanthium L. A review of its systematics demonstrates that many so-called "species" described on material from Europe actually have their origin in America, except one, X. strumarium s. str., which seems to have a Mediterranean–European center of dispersal. Another conclusion drawn is that Xanthium consists of only two distinct species: X. spinosum L. and X. strumarium L. The former is a relatively stable species, the latter an enormously variable one readily subdivided into a number of minor taxonomic entities.Ecologically, in eastern North America at least, Xanthium is primarily a beach plant, which prefers open habitats and succumbs to crowding. The seeds are most often dispersed by water and wind. It enters easily into ruderal habitats, but only as long as these are open and unshaded.The generalized short-day flowering response in this genus supports our hypothesis that Xanthium has a tropical–subtropical origin, and we feel that it has its center in Central and/or South America, whence it has spread over the continents north and southward.There is no evidence for any sterility barriers separating the entities of X. strumarium, but we feel that an intense inbreeding with an occasional outbreeding is responsible for the enormous variation, often resulting in small, local, but unstable taxa.

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Malarial parasites as geographical markers in migratory birds?

Biology Letters ◽

10.1098/rsbl.2005.0429 ◽

2006 ◽

Vol 2 (2) ◽

pp. 213-216 ◽

Cited By ~ 31

Author(s):

Sylvia M Fallon ◽

Robert C Fleischer ◽

Gary R Graves

Keyword(s):

North America ◽

Migratory Birds ◽

Wide Distribution ◽

Specific Information ◽

Population Movements ◽

Site Specific ◽

Dendroica Caerulescens ◽

Bird Populations ◽

Breeding Populations ◽

Wintering Range

We tested the hypothesis that malarial parasites ( Plasmodium and Haemoproteus ) of black-throated blue warblers ( Dendroica caerulescens ) provide sufficient geographical signal to track population movements between the warbler's breeding and wintering habitats in North America. Our results from 1083 warblers sampled across the species' breeding range indicate that parasite lineages are geographically widespread and do not provide site-specific information. The wide distribution of malarial parasites probably reflects postnatal dispersal of their hosts as well as mixing of breeding populations on the wintering range. When compared to geographically structured parasites of sedentary Caribbean songbirds, patterns of malarial infections in black-throated blue warblers suggest that host–malaria dynamics of migratory and sedentary bird populations may be subject to contrasting selection pressures.

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