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1.
PLoS One ; 18(3): e0282178, 2023.
Article in English | MEDLINE | ID: mdl-36862709

ABSTRACT

Deserts are stressful environments where the living beings must acquire different strategies to survive due to the water stress conditions. From the late Albian to the early Cenomanian, the northern and eastern parts of Iberia were the location of the desert system represented by deposits assigned to the Utrillas Group, which bear abundant amber with numerous bioinclusions, including diverse arthropods and vertebrate remains. In the Maestrazgo Basin (E Spain), the late Albian to early Cenomanian sedimentary succession represents the most distal part of the desert system (fore-erg) that was characterised by an alternation of aeolian and shallow marine sedimentary environments in the proximity of the Western Tethys palaeo-coast, with rare to frequent dinoflagellate cysts. The terrestrial ecosystems from this area were biodiverse, and comprised plant communities whose fossils are associated with sedimentological indicators of aridity. The palynoflora dominated by wind-transported conifer pollen is interpreted to reflect various types of xerophytic woodlands from the hinterlands and the coastal settings. Therefore, fern and angiosperm communities abundantly grew in wet interdunes and coastal wetlands (temporary to semi-permanent freshwater/salt marshes and water bodies). In addition, the occurrence of low-diversity megafloral assemblages reflects the existence of coastal salt-influenced settings. The palaeobotanical study carried out in this paper which is an integrative work on palynology and palaeobotany, does not only allow the reconstruction of the vegetation that developed in the mid-Cretaceous fore-erg from the eastern Iberia, in addition, provides new biostratigraphic and palaeogeographic data considering the context of angiosperm radiation as well as the biota inferred in the amber-bearing outcrops of San Just, Arroyo de la Pascueta and La Hoya (within Cortes de Arenoso succesion). Importantly, the studied assemblages include Afropollis, Dichastopollenites, Cretacaeiporites together with pollen produced by Ephedraceae (known for its tolerance to arid conditions). The presence of these pollen grains, typical for northern Gondwana, associates the Iberian ecosystems with those characterising the mentioned region.


Subject(s)
Amber , Ecosystem , Biodiversity , Biota , Pollen
2.
Elife ; 102021 11 30.
Article in English | MEDLINE | ID: mdl-34844669

ABSTRACT

Dinosaur bonebeds with amber content, yet scarce, offer a superior wealth and quality of data on ancient terrestrial ecosystems. However, the preserved palaeodiversity and/or taphonomic characteristics of these exceptional localities had hitherto limited their palaeobiological potential. Here, we describe the amber from the Lower Cretaceous dinosaur bonebed of Ariño (Teruel, Spain) using a multidisciplinary approach. Amber is found in both a root layer with amber strictly in situ and a litter layer mainly composed of aerial pieces unusually rich in bioinclusions, encompassing 11 insect orders, arachnids, and a few plant and vertebrate remains, including a feather. Additional palaeontological data-charophytes, palynomorphs, ostracods- are provided. Ariño arguably represents the most prolific and palaeobiologically diverse locality in which fossiliferous amber and a dinosaur bonebed have been found in association, and the only one known where the vast majority of the palaeontological assemblage suffered no or low-grade pre-burial transport. This has unlocked unprecedentedly complete and reliable palaeoecological data out of two complementary windows of preservation-the bonebed and the amber-from the same site.


Subject(s)
Amber , Dinosaurs , Fossils , Animals , Biodiversity , Forests , Soil , Spain , Wetlands
3.
Sci Rep ; 10(1): 9751, 2020 06 16.
Article in English | MEDLINE | ID: mdl-32546844

ABSTRACT

Fossilized remains preserved in amber provide abundant data on the paleobiota surrounding the resin-producing plants, but relatively scarcer information about the resinous sources themselves. Here, dark pseudoinclusions in kidney-shaped amber pieces from the Early Cretaceous (Albian) amber from Spain are studied. This type of fossilized remain, abundant in Cretaceous ambers, was first interpreted as fossilized vacuole-bearing microorganisms, but later regarded as artifactual and probably secreted by the resinous trees, although their origin remained unclear. Using complementary microscopy (light, electron, confocal), spectroscopy (infrared, micro-Raman), mass spectrometry and elemental analysis techniques, we demonstrate that the pseudoinclusions correspond to droplets of phloem sap containing amber spheroids and preserving both organic and inorganic residues consistent with degraded components from the original sap. The amber pieces containing pseudoinclusions are fossilized, resin-in-sap-in-resin double emulsions, showing banding patterns with differential content of resin-in-sap emulsion droplets. Our findings represent the first time fossilized phloem sap, 105 million years old, has been recognized and characterized, and open new lines of paleontological research with taxonomic, taphonomic, physiological and ecological implications.


Subject(s)
Amber/chemistry , Fossils/diagnostic imaging , Paleontology/methods , Amber/analysis , Emulsions/analysis , Microscopy, Electron, Scanning/methods , Phloem/chemistry , Preservation, Biological/methods , Spain , Spectroscopy, Fourier Transform Infrared/methods , Spectrum Analysis, Raman/methods
4.
iScience ; 23(3): 100913, 2020 Mar 27.
Article in English | MEDLINE | ID: mdl-32191877

ABSTRACT

The Cretaceous fossil record of amber provides a variety of evidence that is essential for greater understanding of early pollination strategies. Here, we describe four pieces of ca. 99-million-year-old (early Cenomanian) Myanmar amber from Kachin containing four closely related genera of short-winged flower beetles (Coleoptera: Kateretidae) associated with abundant pollen grains identified as three distinct palynomorphotypes of the gymnosperm Cycadopites and Praenymphaeapollenites cenomaniensis gen. and sp. nov., a form-taxon of pollen from a basal angiosperm lineage of water lilies (Nymphaeales: Nymphaeaceae). We demonstrate how a gymnosperm to angiosperm plant-host shift occurred during the mid-Cretaceous, from a generalist pollen-feeding family of beetles, which served as a driving mechanism for the subsequent success of flowering plants.

5.
Commun Biol ; 2: 408, 2019.
Article in English | MEDLINE | ID: mdl-31728419

ABSTRACT

Angiosperms and their insect pollinators form a foundational symbiosis, evidence for which from the Cretaceous is mostly indirect, based on fossils of insect taxa that today are anthophilous, and of fossil insects and flowers that have apparent anthophilous and entomophilous specializations, respectively. We present exceptional direct evidence preserved in mid-Cretaceous Burmese amber, 100 mya, for feeding on pollen in the eudicot genus Tricolporoidites by a basal new aculeate wasp, Prosphex anthophilos, gen. et sp. nov., in the lineage that contains the ants, bees, and other stinging wasps. Plume of hundreds of pollen grains wafts from its mouth and an apparent pollen mass was detected by micro-CT in the buccal cavity: clear evidence that the wasp was foraging on the pollen. Eudicots today comprise nearly three-quarters of all angiosperm species. Prosphex feeding on Tricolporoidites supports the hypothesis that relatively small, generalized insect anthophiles were important pollinators of early angiosperms.


Subject(s)
Pollen , Wasps/physiology , Amber/history , Animals , Diet/history , Fossils , History, Ancient , Magnoliopsida/ultrastructure , Myanmar , Pollen/ultrastructure , Pollination/physiology , Preservation, Biological , Wasps/anatomy & histology , Wasps/classification , X-Ray Microtomography
6.
Am J Trop Med Hyg ; 99(2): 297-302, 2018 08.
Article in English | MEDLINE | ID: mdl-29943707

ABSTRACT

Ehrlichia spp. are emerging infectious pathogens, especially in the Americas. Although Ehrlichia canis is primarily a parasite of dogs, polymerase chain reaction-confirmed human infections have been reported from Mexico, Venezuela, and Costa Rica. This study reports the presence of E. canis DNA in 13.7% of 205 dogs from urban areas in Peru and of those, five were analyzed for phylogenetic variation using the Tandem Repeat Protein 36 (TRP36) gene. The use of the TRP36 gene for such analysis was validated against 16S rRNA and heat shock protein genes using Shannon's entropy bioinformatic approach. When compared with other E. canis strains previously reported, three unique and novel E. canis strains were detected. In addition, the TRP36 amino acid tandem repeat sequences of the Peruvian strains share close similarity to an E. canis strain detected from four human blood bank samples in Costa Rica. This study reports for the first time domestic dogs infected with E. canis strains closely related to a zoonotic strain, which may be of public health concern as dogs can be chronically infected with this pathogen.


Subject(s)
Bacterial Proteins/genetics , Dogs/microbiology , Ehrlichia canis/genetics , Ehrlichiosis/veterinary , Tandem Repeat Sequences , Animals , Bacterial Proteins/isolation & purification , Computational Biology , DNA, Bacterial/genetics , Dog Diseases/epidemiology , Dog Diseases/microbiology , Ehrlichia canis/isolation & purification , Ehrlichiosis/epidemiology , Female , Male , Peru/epidemiology , Phylogeny , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
7.
Curr Biol ; 27(6): 897-904, 2017 Mar 20.
Article in English | MEDLINE | ID: mdl-28262492

ABSTRACT

During the mid-Cretaceous, angiosperms diversified from several nondiverse lineages to their current global domination [1], replacing earlier gymnosperm lineages [2]. Several hypotheses explain this extensive radiation [3], one of which involves proliferation of insect pollinator associations in the transition from gymnosperm to angiosperm dominance. However, most evidence supports gymnosperm-insect pollinator associations, buttressed by direct evidence of pollen on insect bodies, currently established for four groups: Thysanoptera (thrips), Neuroptera (lacewings), Diptera (flies), and now Coleoptera (beetles). Each group represents a distinctive pollination mode linked to a unique mouthpart type and feeding guild [4-9]. Extensive indirect evidence, based on specialized head and mouthpart morphology, is present for one of these pollinator types, the long-proboscid pollination mode [10], representing minimally ten family-level lineages of Neuroptera, Mecoptera (scorpionflies), and Diptera [8, 10, 11]. A recurring feature uniting these pollinator modes is host associations with ginkgoalean, cycad, conifer, and bennettitalean gymnosperms. Pollinator lineages bearing these pollination modes were categorized into four evolutionary cohorts during the 35-million-year-long angiosperm radiation, each defined by its host-plant associations (gymnosperm or angiosperm) and evolutionary pattern (extinction, continuation, or origination) during this interval [12]. Here, we provide the first direct evidence for one cohort, exemplified by the beetle Darwinylus marcosi, family Oedemeridae (false blister beetles), that had an earlier gymnosperm (most likely cycad) host association, later transitioning onto angiosperms [13]. This association constitutes one of four patterns explaining the plateau of family-level plant lineages generally and pollinating insects specifically during the mid-Cretaceous angiosperm radiation [12].


Subject(s)
Biological Evolution , Coleoptera/anatomy & histology , Cycadopsida/physiology , Fossils/anatomy & histology , Pollination , Animals , Coleoptera/physiology , Pollen/anatomy & histology
8.
Curr Biol ; 25(14): 1917-23, 2015 Jul 20.
Article in English | MEDLINE | ID: mdl-26166781

ABSTRACT

The great evolutionary success of angiosperms has traditionally been explained, in part, by the partnership of these plants with insect pollinators. The main approach to understanding the origins of this pervasive relationship has been study of the pollinators of living cycads, gnetaleans, and basal angiosperms. Among the most morphologically specialized living pollinators are diverse, long-proboscid flies. Early such flies include the brachyceran family Zhangsolvidae, previously known only as compression fossils from the Early Cretaceous of China and Brazil. It belongs to the infraorder Stratiomyomorpha, a group that includes the flower-visiting families Xylomyidae and Stratiomyidae. New zhangsolvid specimens in amber from Spain (ca. 105 mega-annum [Ma]) and Myanmar (100 Ma) reveal a detailed proboscis structure adapted to nectivory. Pollen clumped on a specimen from Spain is Exesipollenites, attributed to a Mesozoic gymnosperm, most likely the Bennettitales. Late Mesozoic scorpionflies with a long proboscis have been proposed as specialized pollinators of various extinct gymnosperms, but pollen has never been observed on or in their bodies. The new discovery is a very rare co-occurrence of pollen with its insect vector and provides substantiating evidence that other long-proboscid Mesozoic insects were gymnosperm pollinators. Evidence is thus now gathering that visitors and probable pollinators of early anthophytes, or seed plants, involved some insects with highly specialized morphological adaptations, which has consequences for interpreting the reproductive modes of Mesozoic gymnosperms and the significance of insect pollination in angiosperm success.


Subject(s)
Cycadopsida/physiology , Diptera/physiology , Pollination , Amber , Animals , Diptera/ultrastructure , Fossils/ultrastructure , Microscopy, Electron, Transmission , Myanmar , Spain
9.
Ann Bot ; 114(2): 301-13, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24941998

ABSTRACT

BACKGROUND AND AIMS: Several studies show apparently contradictory findings about the functional convergence within the Mediterranean woody flora. In this context, this study evaluates the variability of functional traits within holm oak (Quercus ilex) to elucidate whether provenances corresponding to different morphotypes represent different ecotypes locally adapted to the prevaling stress levels. METHODS: Several morphological and physiological traits were measured at leaf and shoot levels in 9-year-old seedlings of seven Q. ilex provenances including all recognized morphotypes. Plants were grown in a common garden for 9 years under the same environmental conditions to avoid possible biases due to site-specific characteristics. KEY RESULTS: Leaf morphometry clearly separates holm oak provenances into 'ilex' (more elongated leaves with low vein density) and 'rotundifolia' (short and rounded leaves with high vein density) morphotypes. Moreover, these morphotypes represent two consistent and very contrasting functional types in response to dry climates, mainly in terms of leaf area, major vein density, leaf specific conductivity, resistance to drought-induced cavitation and turgor loss point. CONCLUSIONS: The 'ilex' and 'rotundifolia' morphotypes correspond to different ecotypes as inferred from their contrasting functional traits. To the best of our knowledge, this is the first time that the combined use of morphological and physiological traits has provided support for the concept of these two holm oak morphotypes being regarded as two different species.


Subject(s)
Biodiversity , Climate , Droughts , Ecotype , Quercus/anatomy & histology , Quercus/physiology , Geography , Mediterranean Region , Plant Leaves/anatomy & histology , Plant Leaves/physiology , Pressure , Principal Component Analysis , Quantitative Trait, Heritable
10.
PLoS Negl Trop Dis ; 7(9): e2393, 2013.
Article in English | MEDLINE | ID: mdl-24040427

ABSTRACT

Bartonella species are emerging infectious organisms transmitted by arthropods capable of causing long-lasting infection in mammalian hosts. Among over 30 species described from four continents to date, 15 are known to infect humans, with eight of these capable of infecting dogs as well. B. bacilliformis is the only species described infecting humans in Peru; however, several other Bartonella species were detected in small mammals, bats, ticks, and fleas in that country. The objective of this study was to determine the serological and/or molecular prevalence of Bartonella species in asymptomatic dogs in Peru in order to indirectly evaluate the potential for human exposure to zoonotic Bartonella species. A convenient sample of 219 healthy dogs was obtained from five cities and three villages in Peru. EDTA-blood samples were collected from 205 dogs, whereas serum samples were available from 108 dogs. The EDTA-blood samples were screened by PCR followed by nucleotide sequencing for species identification. Antibodies against B. vinsonii berkhoffii and B. rochalimae were detected by IFA (cut-off of 1∶64). Bartonella DNA was detected in 21 of the 205 dogs (10%). Fifteen dogs were infected with B. rochalimae, while six dogs were infected with B. v. berkhoffii genotype III. Seropositivity for B. rochalimae was detected in 67 dogs (62%), and for B. v. berkhoffii in 43 (40%) of the 108 dogs. Reciprocal titers ≥1∶256 for B. rochalimae were detected in 19% of dogs, and for B. v. berkhoffii in 6.5% of dogs. This study identifies for the first time a population of dogs exposed to or infected with zoonotic Bartonella species, suggesting that domestic dogs may be the natural reservoir of these zoonotic organisms. Since dogs are epidemiological sentinels, Peruvian humans may be exposed to infections with B. rochalimae or B. v. berkhoffii.


Subject(s)
Bartonella Infections/veterinary , Bartonella/isolation & purification , Carrier State/veterinary , Dog Diseases/epidemiology , Dog Diseases/microbiology , Animals , Antibodies, Bacterial/blood , Asymptomatic Diseases , Bartonella/classification , Bartonella/genetics , Bartonella Infections/epidemiology , Bartonella Infections/microbiology , Carrier State/epidemiology , Carrier State/microbiology , Cross-Sectional Studies , DNA, Bacterial/blood , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Dogs , Female , Fluorescent Antibody Technique, Indirect , Male , Molecular Sequence Data , Peru/epidemiology , Polymerase Chain Reaction , Prevalence , Sequence Analysis, DNA
11.
Proc Natl Acad Sci U S A ; 109(22): 8623-8, 2012 May 29.
Article in English | MEDLINE | ID: mdl-22615414

ABSTRACT

Within modern gymnosperms, conifers and Ginkgo are exclusively wind pollinated whereas many gnetaleans and cycads are insect pollinated. For cycads, thrips are specialized pollinators. We report such a specialized pollination mode from Early Cretaceous amber of Spain, wherein four female thrips representing a genus and two species in the family Melanthripidae were covered by abundant Cycadopites pollen grains. These females bear unique ring setae interpreted as specialized structures for pollen grain collection, functionally equivalent to the hook-tipped sensilla and plumose setae on the bodies of bees. The most parsimonious explanation for this structure is parental food provisioning for larvae, indicating subsociality. This association provides direct evidence of specialized collection and transportation of pollen grains and likely gymnosperm pollination by 110-105 million years ago, possibly considerably earlier.


Subject(s)
Cycadopsida/physiology , Pollen/physiology , Pollination/physiology , Thysanoptera/physiology , Animals , Biological Evolution , Cycadopsida/classification , Cycadopsida/parasitology , Female , Host-Parasite Interactions , Paleontology/methods , Spain , Species Specificity , Thysanoptera/anatomy & histology , Thysanoptera/classification
12.
PLoS Negl Trop Dis ; 6(4): e1462, 2012.
Article in English | MEDLINE | ID: mdl-22509413

ABSTRACT

Echinococcus granulosus infections are a major public health problem in livestock-raising regions around the world. The life cycle of this tapeworm is sustained between dogs (definitive host, canine echinococcosis), and herbivores (intermediary host, cystic hydatid disease). Humans may also develop cystic hydatid disease. Echinococcosis is endemic in rural areas of Peru; nevertheless, its presence or the extension of the problem in urban areas is basically unknown. Migration into Lima, an 8-million habitant's metropolis, creates peripheral areas where animals brought from endemic areas are slaughtered without veterinary supervision. We identified eight informal, unlicensed abattoirs in a peripheral district of Lima and performed a cross-sectional study in to assess the prevalence of canine echinococcosis, evaluated by coproELISA followed by PCR evaluation and arecoline purge. Eight of 22 dogs (36%) were positive to coproELISA, and four (18%) were confirmed to be infected with E. granulosus tapeworms either by PCR or direct observation (purge). Later evaluation of the human population living in these abattoirs using abdominal ultrasound, chest X-rays and serology, found 3 out of 32 (9.3%) subjects with echinococcal cysts in the liver (two viable, one calcified), one of whom had also lung involvement and a strongly positive antibody response. Autochthonous transmission of E. granulosus is present in Lima. Informal, unlicensed abattoirs may be sources of infection to neighbouring people in this urban environment.


Subject(s)
Abattoirs , Dog Diseases/epidemiology , Echinococcosis/epidemiology , Echinococcosis/veterinary , Echinococcus granulosus/isolation & purification , Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Cross-Sectional Studies , Dog Diseases/parasitology , Dogs , Echinococcosis/diagnosis , Echinococcosis/parasitology , Enzyme-Linked Immunosorbent Assay , Feces/parasitology , Female , Humans , Male , Middle Aged , Peru/epidemiology , Polymerase Chain Reaction , Prevalence , Urban Population , Young Adult
13.
PLoS Negl Trop Dis ; 4(2): e616, 2010 Feb 23.
Article in English | MEDLINE | ID: mdl-20186332

ABSTRACT

BACKGROUND: Cystic Echinococosis (CE) is a zoonotic disease caused by larval stage Echinococcus granulosus. We determined the effects of high dose of Oxfendazole (OXF), combination Oxfendazole/Praziquantel (PZQ), and combination Albendazole (ABZ)/Praziquantel against CE in sheep. METHODOLOGY/PRINCIPAL FINDINGS: A randomized placebo-controlled trial was carried out on 118 randomly selected ewes. They were randomly assigned to one of the following groups: 1) placebo; 2) OXF 60 mg/Kg of body weight (BW) weekly for four weeks; 3) ABZ 30 mg/Kg BW + PZQ 40 mg/Kg BW weekly for 6 weeks, and 4) OXF 30 mg/Kg BW+ PZQ 40 mg/Kg BW biweekly for 3 administrations (6 weeks). Percent protoscolex (PSC) viability was evaluated using a 0.1% aqueous eosin vital stain for each cyst. "Noninfective" sheep were those that had no viable PSCs; "low-medium infective" were those that had 1% to 60% PSC viability; and "high infective" were those with more than 60% PSC viability. We evaluated 92 of the 118 sheep. ABZ/PZQ led the lowest PSC viability for lung cysts (12.7%), while OXF/PZQ did so for liver cysts (13.5%). The percentage of either "noninfective" or "low-medium infective" sheep was 90%, 93.8% and 88.9% for OXF, ABZ/PZQ and OXF/PZQ group as compared to 50% "noninfective" or "low-medium infective" for placebo. After performing all necropsies, CE prevalence in the flock of sheep was 95.7% (88/92) with a total number of 1094 cysts (12.4 cysts/animal). On average, the two-drug-combination groups resulted pulmonary cysts that were 6 mm smaller and hepatic cysts that were 4.2 mm smaller than placebo (p<0.05). CONCLUSIONS/SIGNIFICANCE: We demonstrate that Oxfendazole at 60 mg, combination Oxfendazole/Praziquantel and combination Albendazole/Praziquantel are successful schemas that can be added to control measures in animals and merits further study for the treatment of animal CE. Further investigations on different schedules of monotherapy or combined chemotherapy are needed, as well as studies to evaluate the safety and efficacy of Oxfendazole in humans.


Subject(s)
Albendazole/therapeutic use , Anthelmintics/therapeutic use , Benzimidazoles/therapeutic use , Echinococcosis/veterinary , Echinococcus granulosus/isolation & purification , Praziquantel/therapeutic use , Sheep Diseases/drug therapy , Animals , Benzimidazoles/administration & dosage , Drug Therapy, Combination , Echinococcosis/drug therapy , Echinococcosis/parasitology , Echinococcus granulosus/drug effects , Sheep Diseases/parasitology , Survival Analysis , Treatment Outcome
14.
Am J Trop Med Hyg ; 80(3): 367-72, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19270283

ABSTRACT

Cystic echinococosis (CE) is a public health problem caused by Echinococcus granulosus. We aimed to determine the efficacy of nitazoxanide (NTZ) and oxfendazole (OXF) against CE in naturally infected sheep. A total of 151 ewes were assigned to the following groups: 15 mg/kg of NTZ weekly for five weeks (NTZ5); two rounds of 15 mg/ kg of NTZ a day for five days (NTZ5x2) two weeks apart; 30 mg/kg of OXF a week for 11 weeks (OXF11); 30 mg/kg of OXF plus 15 mg/kg of NTZ a week for 11 weeks (OXF/NTZ); and the control group. OXF11 and OXF/NTZ decreased the number of fertile cysts, increased the number of degenerated cysts, and were more efficacious (49.6-61.2%) against lung cysts and liver cysts (91.8-100%) than any other treatment group. OXF might be an additional strategy for control programs and an optional treatment of human CE after it is licensed.


Subject(s)
Antiparasitic Agents/therapeutic use , Benzimidazoles/therapeutic use , Echinococcosis, Hepatic/veterinary , Echinococcosis, Pulmonary/veterinary , Sheep Diseases/drug therapy , Thiazoles/therapeutic use , Animals , Echinococcosis, Hepatic/drug therapy , Echinococcosis, Pulmonary/drug therapy , Female , Nitro Compounds , Sheep
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