scholarly journals Exceptional preservation of mid-Cretaceous marine arthropods and the evolution of novel forms via heterochrony

2019 ◽  
Vol 5 (4) ◽  
pp. eaav3875 ◽  
Author(s):  
J. Luque ◽  
R. M. Feldmann ◽  
O. Vernygora ◽  
C. E. Schweitzer ◽  
C. B. Cameron ◽  
...  
Keyword(s):  
United States ◽  
Early Cretaceous ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Body Plan ◽  
Compound Eyes ◽  
Exceptional Preservation ◽  
Evolutionary Origins ◽  
Morphological Transformations ◽  
Active Swimming

Evolutionary origins of novel forms are often obscure because early and transitional fossils tend to be rare, poorly preserved, or lack proper phylogenetic contexts. We describe a new, exceptionally preserved enigmatic crab from the mid-Cretaceous of Colombia and the United States, whose completeness illuminates the early disparity of the group and the origins of novel forms. Its large and unprotected compound eyes, small fusiform body, and leg-like mouthparts suggest larval trait retention into adulthood via heterochronic development (pedomorphosis), while its large oar-like legs represent the earliest known adaptations in crabs for active swimming. Our phylogenetic analyses, including representatives of all major lineages of fossil and extant crabs, challenge conventional views of their evolution by revealing multiple convergent losses of a typical “crab-like” body plan since the Early Cretaceous. These parallel morphological transformations may be associated with repeated invasions of novel environments, including the pelagic/necto-benthic zone in this pedomorphic chimera crab.

scholarly journals Phenotypic and molecular characterization of a novel strongly hemolytic Brachyspira species, provisionally designated “Brachyspira hampsonii”

2012 ◽  
Vol 24 (5) ◽  
pp. 903-910 ◽  
Author(s):  
Yogesh Chander ◽  
Alexander Primus ◽  
Simone Oliveira ◽  
Connie J. Gebhart
Keyword(s):  
United States ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Diagnostic Laboratory ◽  
Brachyspira Hyodysenteriae ◽  
Phylogenetic Grouping ◽  
Enzymatic Profiling ◽  
Swine Herds

Since 2007, outbreaks of severe bloody diarrhea and hemorrhagic colitis have been reported in the United States and Canada. Though the primary causative agent of swine dysentery is Brachyspira hyodysenteriae, which is strongly hemolytic, the current report describes the isolation of a novel strongly hemolytic Brachyspira sp. This novel Brachyspira sp. was identified from clinical submissions at the Minnesota Veterinary Diagnostic Laboratory, and 40 of such isolates were obtained from 22 clinical submissions representing 5 states. Isolates were confirmed to be different from any known Brachyspira sp. on the basis of phylogenetic analysis of nucleotide sequences of nox and 16S ribosomal RNA (rRNA) genes. Phylogenetic analyses grouped all isolates into 2 clades (clades I and II), and grouping patterns were similar for both nox and 16S rRNA gene sequence analyses. Phenotypically, all isolates were indole and hippurate negative, and enzymatic profiling indicated 2 types of profiles, irrespective of the phylogenetic grouping, differing only in the production of β-glucosidase. The results suggest that a potentially virulent new species of Brachyspira sp., provisionally named “ Brachyspira hampsonii ”, is circulating among swine herds in the United States.

scholarly journals Veterinary Fusarioses within the United States

2016 ◽  
Vol 54 (11) ◽  
pp. 2813-2819 ◽  
Author(s):  
Kerry O'Donnell ◽  
Deanna A. Sutton ◽  
Nathan Wiederhold ◽  
Vincent A. R. G. Robert ◽  
Pedro W. Crous ◽  
...  
Keyword(s):  
United States ◽  
Dna Sequence ◽  
Species Complex ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
The United States ◽  
Content Type ◽  
Dna Sequence Data ◽  
Species Complexes

Multilocus DNA sequence data were used to assess the genetic diversity and evolutionary relationships of 67Fusariumstrains from veterinary sources, most of which were from the United States. Molecular phylogenetic analyses revealed that the strains comprised 23 phylogenetically distinct species, all but two of which were previously known to infect humans, distributed among eight species complexes. The majority of the veterinary isolates (47/67 = 70.1%) were nested within theFusarium solanispecies complex (FSSC), and these included 8 phylospecies and 33 unique 3-locus sequence types (STs). Three of the FSSC species (Fusarium falciforme,Fusarium keratoplasticum, andFusariumsp. FSSC 12) accounted for four-fifths of the veterinary strains (38/47) and STs (27/33) within this clade. Most of theF. falciformestrains (12/15) were recovered from equine keratitis infections; however, strains ofF. keratoplasticumandFusariumsp. FSSC 12 were mostly (25/27) isolated from marine vertebrates and invertebrates. Our sampling suggests that theFusarium incarnatum-equisetispecies complex (FIESC), with eight mycoses-associated species, may represent the second most important clade of veterinary relevance withinFusarium. Six of the multilocus STs within the FSSC (3+4-eee, 1-b, 12-a, 12-b, 12-f, and 12-h) and one each within the FIESC (1-a) and theFusarium oxysporumspecies complex (ST-33) were widespread geographically, including three STs with transoceanic disjunctions. In conclusion, fusaria associated with veterinary mycoses are phylogenetically diverse and typically can only be identified to the species level using DNA sequence data from portions of one or more informative genes.

scholarly journals Phomopsis Stem Canker: A Reemerging Threat to Sunflower (Helianthus annuus) in the United States

2015 ◽  
Vol 105 (7) ◽  
pp. 990-997 ◽  
Author(s):  
Febina M. Mathew ◽  
Kholoud M. Alananbeh ◽  
James G. Jordahl ◽  
Scott M. Meyer ◽  
Lisa A. Castlebury ◽  
...  
Keyword(s):  
United States ◽  
Helianthus Annuus ◽  
Great Plains ◽  
Phylogenetic Analyses ◽  
Elongation Factor ◽  
Stem Canker ◽  
The United States ◽  
Northern Great Plains ◽  
Type Specimens ◽  
Internal Transcribed Spacer Region

Phomopsis stem canker causes yield reductions on sunflower (Helianthus annuus L.) on several continents, including Australia, Europe, and North America. In the United States, Phomopsis stem canker incidence has increased 16-fold in the Northern Great Plains between 2001 and 2012. Although Diaporthe helianthi was assumed to be the sole causal agent in the United States, a newly described species, D. gulyae, was found to be the primary cause of Phomopsis stem canker in Australia. To determine the identity of Diaporthe spp. causing Phomopsis stem canker in the Northern Great Plains, 275 infected stems were collected between 2010 and 2012. Phylogenetic analyses of sequences of the ribosomal DNA internal transcribed spacer region, elongation factor subunit 1-α, and actin gene regions of representative isolates, in comparison with those of type specimens, confirmed two species (D. helianthi and D. gulyae) in the United States. Differences in aggressiveness between the two species were determined using the stem-wound method in the greenhouse; overall, D. helianthi and D. gulyae did not vary significantly (P ≤ 0.05) in their aggressiveness at 10 and 14 days after inoculation. These findings indicate that both Diaporthe spp. have emerged as sunflower pathogens in the United States, and have implications on the management of this disease.

scholarly journals Common Ancestry of Borrelia burgdorferiSensu Lato Strains from North America and Europe

1999 ◽  
Vol 37 (9) ◽  
pp. 3010-3012 ◽  
Author(s):  
D. Postic ◽  
N. Marti Ras ◽  
R. S. Lane ◽  
P.-F. Humair ◽  
M. M. Wittenbrink ◽  
...  
Keyword(s):  
United States ◽  
North America ◽  
Borrelia Burgdorferi ◽  
North American ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Whole Genome ◽  
Common Ancestry ◽  
Limited Region

Ten atypical European Borrelia burgdorferi sensu lato (Borrelia spp.) strains were genetically characterized, and the diversity was compared to that encountered among relatedBorrelia spp. from North America. Phylogenetic analyses of a limited region of the genome and of the whole genome extend existing knowledge about borrelial diversity reported earlier in Europe and the United States. Our results accord with the evidence that North American and European strains may have a common ancestry.

scholarly journals Recent Outbreak of Soybean Sudden Death Syndrome Caused by Fusarium virguliforme and F. tucumaniae in Argentina

Plant Disease ◽  
2004 ◽  
Vol 88 (9) ◽  
pp. 1044-1044 ◽  
Author(s):  
M. Scandiani ◽  
D. Ruberti ◽  
K. O'Donnell ◽  
T. Aoki ◽  
R. Pioli ◽  
...  
Keyword(s):  
United States ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Positive Control ◽  
Koch’S Postulates ◽  
First Report ◽  
Molecular Phylogenetic ◽  
Soil Infestation ◽  
Pathogenicity Tests ◽  
Koch's Postulates

Sudden death syndrome (SDS) of soybean was detected initially in Argentina during 1991-1992 in the Pampas Region and 1992-1993 in the Northwest Region. The first report of the fulfillment of Koch's postulates of SDS caused by Fusarium solani f. sp. glycines in Argentina was published in 2003 (3). Subsequently, analyses have shown that F. solani f. sp. glycines represents several morphologically and phylogenetically distinct species, including F. tucumaniae in Argentina and F. virguliforme in the United States (1). Isolations were made from plants that exhibited typical SDS symptoms (interveinal foliar chlorosis and necrosis leading to defoliation of the leaflets but not the petioles) from fields in Santa Fe and Buenos Aires provinces in 2001, 2002, and 2003. To determine which species are responsible for SDS in Argentina, cultures of eight slow growing isolates that developed bluish pigmentation and produced abundant macroconidia in sporodochia on potato dextrose agar were subjected to morphological and molecular phylogenetic analyses and pathogenicity tests. Morphological analyses demonstrated that three of the isolates were F. virguliforme and five were F. tucumaniae. Isolates of F. tucumaniae produced long and narrow sporodochial conidia while F. virguliforme produced diagnostic comma-shaped conidia. Molecular phylogenetic analyses of DNA sequences from multiple loci confirmed morphology-based identifications and showed that the soybean SDS pathogen in the United States, F. virguliforme, was also present in Argentina. To our knowledge, this is the first report of F. virguliforme in Argentina and of this pathogen outside the United States. Five isolates of F. tucumaniae and three isolates of F. virguliforme were used for pathogenicity tests. F. virguliforme isolate 171 provided by J. Rupe (University of Arkansas, Fayetteville) was used as a positive control. Soybean cultivars Ripley, RA 702, Pioneer 9492RR, Spencer, and A-6445RG were inoculated with each of the isolates tested in a greenhouse assay using soil infestation and toothpick methods (2). All eight isolates produced typical foliar SDS symptoms 15 to 25 days after inoculation. Severity of foliar symptoms averaged 3.3 for F. virguliforme, 2.6 for F. tucumaniae, and 3.3 for the positive control using a disease severity scale in which 1 = no symptoms and 5 = severely infected or dead plants. Under these conditions, F. virguliforme appeared to be more virulent than F tucumaniae. Noninoculated plants remained symptomless. Koch's postulates were confirmed with soybean cultivars RA 702 and A6445RG. Isolates recovered from symptomatic plants inoculated by the soil infestation and toothpick methods were identical to those used to inoculate the plant. Strains were recovered at frequencies of 100 and 60% from plants inoculated by the toothpick and soil infestation methods, respectively. To our knowledge, this is the first report of the fulfillment of Koch's postulates for F. tucumaniae and F. virguliforme in Argentina. References: (1) T. Aoki et al. Mycologia 95:660, 2003. (2) K. W. Roy et al. Plant Dis. 81:1100, 1997 (3) M. Scandiani et al. Plant Dis. 87:447, 2003.

scholarly journals Redescription of Arundel formation Ornithomimosaur material and a reinterpretation of Nedcolbertia justinhofmanni as an “Ostrich Dinosaur”: Biogeographic implications

2016 ◽  
Author(s):  
Chase Doran Brownstein
Keyword(s):  
United States ◽  
North America ◽  
Early Cretaceous ◽  
Fossil Record ◽  
East Coast ◽  
The United States ◽  
Eastern North America ◽  
New Taxon ◽  
Western North America ◽  
The Past

The fossil record of dinosaurs from the Early Cretaceous of eastern North America is scant, and only a few sediments to the east of the continent are fossiliferous. Among them is the Arundel Formation of the east coast of the United States, which has produced among the best dinosaur faunas known from the Early Cretaceous of eastern North America. The diverse dinosaur fauna of this formation has been thoroughly discussed previously, but few of the dinosaur species originally described from the Arundel are still regarded as valid genera. Much of the Arundel material is in need of review and redescription. Among the fossils of dinosaurs from this formation are those referred to ornithomimosaurs. Here, I redescribe ornithomimosaur remains from the Arundel Formation which may warrant the naming of a new taxon of dinosaur. These remains provide key information on the theropods of the Early Cretaceous of Eastern North America. The description of the Arundel material herein along with recent discoveries of basal ornithomimosaurs in the past 15 years has allowed for comparisons with the coelurosaur Nedcolbertia justinhofmanni, suggesting the latter animal was a basal ornithomimosaurian dinosaur rather than a “generalized” coelurosaur. Comparisons between the Arundel ornithomimosaur and similar southeast Asian ornithomimosaurian material as well as ornithomimosaur remains from western North America suggest that a lineage of ornithomimosaurs with a metatarsal condition intermediate between that of basal and derived ornithomimosaurs was present through southeast Asia into North America, in turn suggesting that such animals coexisted with genera having a more primitive metatarsal morphology as seen in N. justinhofmanni.

Diaporthe seed decay of soybean [Glycine max (L.) Merr.] is endemic in the United States, but new fungi are involved

Plant Disease ◽  
2020 ◽  
Author(s):  
Kristina Petrovic ◽  
Demetra Skaltsas ◽  
Lisa Castlebury ◽  
Brian Kontz ◽  
Tom Allen ◽  
...  
Keyword(s):  
United States ◽  
Glycine Max ◽  
Seed Quality ◽  
Phylogenetic Analyses ◽  
Elongation Factor ◽  
The United States ◽  
Post Inoculation ◽  
Seed Decay ◽  
Comprehensive Survey ◽  
Glycine Max L

Diaporthe seed decay can compromise seed quality in soybean [Glycine max (L.) Merr.] in the warm and humid production areas of the United States during crop maturation. In the current study, 45 isolates of Diaporthe were recovered from seed sampled from soybean fields affected by Diaporthe-associated diseases in eight U.S. states in 2017. The isolates obtained belonged to 10 species of Diaporthe based on morphology and phylogenetic analyses of the internal transcribed spacer, the partial translation elongation factor 1-alpha, and beta-tubulin gene sequences. The associated species included D. aspalathi, D. caulivora, D. kongii, D. longicolla, D. sojae, D. ueckerae, D. unshiuensis and three novel fungi, D. bacilloides, D. flavescens and D. insulistroma. One isolate each of the 10 species was examined for pathogenicity on seed of cv. ‘Sava’ under controlled conditions. Seven days post-inoculation, significant differences in the percentages of decayed seeds and seedling necrosis were observed among the isolates and the non-inoculated control (p<0.0001). While the isolates of D. bacilloides, D. longicolla, and D. ueckerae caused significantly greater percentage of decayed seeds (p<0.0001), the isolate of D. aspalathi caused the greatest seedling necrosis (p<0.0001) when compared to the non-inoculated control. The observation of new fungi causing Diaporthe seed decay suggests the need for a more comprehensive survey in the U.S. soybean producing areas since members of the genus Diaporthe appear to form a complex that causes seed decay.

scholarly journals First Report of Puccinia coronata var. coronata sensu stricto Infecting Alder Buckthorn in the United States

2017 ◽  
Vol 18 (2) ◽  
pp. 84-86
Author(s):  
Shawn C. Kenaley ◽  
Geoffrey Ecker ◽  
Gary C. Bergstrom
Keyword(s):  
United States ◽  
North America ◽  
Host Range ◽  
Geographic Distribution ◽  
Phylogenetic Analyses ◽  
Rust Fungus ◽  
The United States ◽  
Sensu Stricto ◽  
Puccinia Coronata ◽  
First Report

Field symptoms, host distribution, pathogen morphology, and phylogenetic analyses clearly demonstrated that the rust fungus infecting alder buckthorn in Connecticut is Puccinia coronata var. coronata sensu stricto. To our knowledge, this is the first report and confirmation of P. coronata var. coronata s.s. in the United States. Additional collections from purported aecial and telial hosts of P. coronata var. coronata s.s. are necessary to determine its host range, geographic distribution, and incidence within the United States and elsewhere in North America.

Molecular comparisons of alphabaculovirus-based products: Gypchek with Disparvirus (Lymantria dispar) and TM BioControl-1 with Virtuss (Orgyia pseudotsugata)

2010 ◽  
Vol 142 (6) ◽  
pp. 546-556 ◽  
Author(s):  
Jianhua Zhang ◽  
Renée Lapointe ◽  
David Thumbi ◽  
Benoit Morin ◽  
Christopher J. Lucarotti
Keyword(s):  
United States ◽  
Lymantria Dispar ◽  
Genomic Dna ◽  
Phylogenetic Analyses ◽  
Rflp Analysis ◽  
The United States ◽  
Amino Acid Sequences ◽  
Open Reading Frames ◽  
Chain Reactions ◽  
Orgyia Pseudotsugata

AbstractGypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), multicapsid nucleopolyhedrovirus (LdMNPV) has been registered as a microbial pest-control product in the United States (Gypchek®) and Canada (Disparvirus®). Similarly, Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough) (Lepidoptera: Lymantriidae), multicapsid nucleopolyhedrovirus (OpMNPV) is registered in the United States and Canada as TM BioControl-1® and a product derived from TM BioControl-1 (Virtuss®) is also registered in Canada. To determine changes that may have occurred in these products over time, we compared DNA from Gypchek with Disparvirus and DNA from TM BioControl-1 with Virtuss using restriction fragment length polymorphism (RFLP) analysis. Gypchek and Disparvirus showed the same RFLP banding patterns when viral genomic DNA was digested with BamH I, EcoR V, and Hind III and only a single band difference at approximately 1.6 kilobase (kb) when digested with Bgl II. TM BioControl-1 and Virtuss showed no differences in genomic DNA when digested with Bgl II, Sam I or Hind III. Twelve viral open reading frames (ORFs) were amplified from Gypchek and Disparvirus and nine from TM BioControl-1 and Virtuss by polymerase chain reactions (PCR). The amplified ORFs ranged from highly conserved (polyhedrin) to least conserved (vp91 capsid associated protein). The products were sequenced and the deduced protein products compared. Amino acid sequences deduced from the sequenced PCR products indicated that 8 of the 12 proteins were identical in the two LdMNPV products. The four proteins showing minor sequence variations were DNA polymerase, LEF-8, P74 envelope protein, and VP 91 capsid associated protein. No differences were detected in the protein products deduced from the nine sequenced ORFs from TM BioControl-1 and Virtuss. Comparative RFLP and protein phylogenetic analyses of Gypchek with Disparvirus and TM BioControl-1 with Virtuss revealed little difference between the respective LdMNPV and OpMNPV populations that make up these product pairs.

scholarly journals Cercospora cf. flagellaris and Cercospora cf. sigesbeckiae Are Associated with Cercospora Leaf Blight and Purple Seed Stain on Soybean in North America

2016 ◽  
Vol 106 (11) ◽  
pp. 1376-1385 ◽  
Author(s):  
S. Albu ◽  
R. W. Schneider ◽  
P. P. Price ◽  
V. P. Doyle
Keyword(s):  
United States ◽  
Sexual Reproduction ◽  
Mating Type ◽  
Phylogenetic Signal ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Leaf Blight ◽  
Internal Transcribed Spacer Region ◽  
Type Locus ◽  
Purple Seed Stain

Cercospora kikuchii has long been considered the causal agent of Cercospora leaf blight (CLB) and purple seed stain (PSS) on soybean, but a recent study found C. cf. flagellaris associated with CLB and PSS in Arkansas (United States) and Argentina. Here, we provide a broader perspective on the distribution of C. cf. flagellaris on soybean and alternate hosts within the United States (Arkansas, Louisiana, Mississippi, Missouri, and Kansas). We used a multilocus phylogenetic approach with data from actin, calmodulin, translation elongation factor 1-α, histone 3, the internal transcribed spacer region of rDNA and the mating-type locus to determine that two species, C. cf. flagellaris (200 of 205 isolates) and C. cf. sigesbeckiae (five of 205 isolates), are associated with CLB and PSS in the United States. In our phylogenetic analyses, species-level lineages were generally well-supported, though deeper-level evolutionary relationships remained unresolved, indicating that these genes do not possess sufficient phylogenetic signal to resolve the evolutionary history of Cercospora. We also investigated the potential for sexual reproduction in C. cf. flagellaris in Louisiana by determining the frequency of MAT1-1/MAT1-2 mating-type idiomorphs within the Louisiana population of C. cf. flagellaris. Though the MAT 1-2 idiomorph was significantly more common in our collection, the presence of both mating types suggests the potential for sexual reproduction exists.

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