The Ixodes auritulus complex (Acari: Parasitiformes: Ixodidae) in the Southern Cone of America.
Ixodes auritulus Neumann, 1904 (Acari: Parasitiformes: Ixodidae) represents a species complex principally associated to birds belonging to the orders Ciconiiformes, Charadriiformes, Columbiformes, Falconiformes, Galliformes, Passeriformes, Piciformes, Pelecaniformes, Procellariiformes, Strigiformes, and Tinamiformes in both immature and adult stages. This is a cosmopolitan tick species whose distribution encompass the Afrotropical, Australasian, Nearctic and Neotropical Zoogeographic Regions, and Pacific Oceans islands. Ixodes auritulus sensu stricto was described from southern Chile, and recently new species from this complex were described based only on morphological characters. In this study, specimens of ticks determined to belong to the I. auritulus complex obtained from the Southern Cone of America in different biogeographic regions of Argentina, southern Chile, Brazil and Uruguay were analyzed. Additionally, a female paratype of Ixodes rio Apanaskevich & Labruna, 2022 from the southern from Brazil was included in the study. Morphological characters were analyzed and phylogenetic analyses were performed by obtaining partial mitochondrial DNA sequences of the 16S rRNA and cox1 genes. The specimens from Punta Arenas, Magallanes Province, southern Chile (type locality) correspond morphologically to I. auritulus s.s. and those from central and northern Argentina (Pampa and Yungas Biogeographic Provinces), Uruguay and southern Brazil (Pampa Biogeographic Province) were morphologically compatible with I. rio. The phylogenetic analysis based on mitochondrial DNA sequences support the classification of I. auritulus s.s. from southern Chile and I. rio from Argentina, Brazil and Uruguay as two distinct species. Additional morphological and molecular analyses of ticks from ecological regions other than those included here are necessary to deepen the knowledge of the diversity of the I. auritulus complex in the Southern Cone of America.
- Research Article
8
- 10.1016/j.ttbdis.2020.101546
- Aug 24, 2020
- Ticks and Tick-borne Diseases
Borrelia genospecies in Ixodes sp. cf. Ixodes affinis (Acari: Ixodidae) from Argentina
- Research Article
23
- 10.1007/s00436-019-06470-z
- Nov 28, 2019
- Parasitology Research
The goal of this study was to clarify the taxonomic status of the Ixodes ricinus complex in the Southern Cone of America, by using morphological characters and molecular markers (mitochondrial 16SrDNA and cox1 genes). The morphological analysis indicates that three different taxa of the I. ricinus complex occur in this region: Ixodes pararicinus, Ixodes aragaoi, and Ixodes sp. cf. I. affinis. The most prominent diagnostic character among them is the size of scutal punctations in both male and female ticks. In the males of Ixodes sp. cf. I. affinis, the punctations on the central field and along the median marginal groove of the scutum are clearly larger than in the males of I. aragaoi and I. pararicinus, while the punctations of I. aragaoi are larger but less numerous than in I. pararicinus. The punctations in Ixodes sp. cf. I. affinis females are larger and deeper than in females of I. aragaoi and I. pararicinus, and those of I. aragaoi are slightly larger than in I. pararicinus. The length of the lateral posterior denticles of the male hypostome is comparatively longer in I. aragaoi than in the other two species, and longer in Ixodes sp. cf. I. affinis than in I. pararicinus. In the 16S analysis, I. pararicinus and I. aragaoi are monophyletic (99% and 98% bootstrap support, respectively), while Ixodes cf. I. affinis does not represent a single lineage. In the cox1 analysis, both I. pararicinus and I. aragaoi are well-defined taxa, but the bootstrap support for Ixodes sp. cf. I. affinis is low (67%). In general, there are considerable 16SrRNA differences among lineages of Ixodes sp. cf. I. affinis from different geographical areas. These results may be indicative of the existence of different species. The populations morphologically compatible with I. affinis from Argentina, Colombia, Panama, Belize, and USA should be provisionally named as Ixodes sp. cf. I. affinis until an integrative taxonomic work with further evidence redefines whether or not this taxon actually represents a species complex.
- Dissertation
2
- 10.14264/uql.2018.216
- Mar 6, 2018
Longnose skates may be one of the most vulnerable taxa of elasmobranch fishes, with documented local extinctions and population declines worldwide. Longnose skates are the main component of the commercial elasmobranch fisheries in the south-east Pacific Ocean, especially in Chilean waters where target and bycatch fisheries have led two species to the brink of collapse. The yellownose skate Zearaja chilensis and the roughskin skate Dipturus trachyderma are endemic of southern South America yet little is known about population ecology and stock structure. Additionally, the external morphology of longnose skates is remarkably similar, especially in early life stages, and a lack of accurate species identification has compromised official landings records which in turn has impacted fishery management. Overall abundance of longnose skates has declined substantially over the last decade due to intensive fishing pressure and the fishery is considered to be `fully exploited'. Based on all available information in peer-reviewed and grey literature, a comparative synthesis of the biology and ecology was conducted on Z. chilensis and D. trachyderma. A positive increase in relation to scientific knowledge over the past decade was noticeable, although several basic aspects of their biology and ecology are still missing. There is an urgent need to fill knowledge gaps on, for example, movement patterns, feeding ecology and habitat use, population size and structure, and levels of connectivity. In this study, taxonomic clarity was provided, and relevant information with regard to the biology, ecology and fisheries that interact with longnose skates was collated. Confusion of identity between longnose skates occurs to the present day. In order to address this issue, morphometric and genetic tools are provided to aid in species identification of early-life stage specimens. Thirty-seven morphometric measurements and three meristic characters were used to identify specimens. These results suggest that the number of midline, nuchal and inter-dorsal thorns could be used to discriminate between specimens of Z. chilensis and D. trachyderma. Previously, the presence of a single nuchal thorn was considered to be a feature that could be used to separate species, however, this morphological feature has proven to be variable in Z. chilensis. Additionally, partial sequences of the 16S, cox1, nadh2 and the control regions of the mitochondrial DNA were amplified and analysed for intraspecific and interspecific divergence. Amplified fragments of cox1 gene and the control region contained information to separate the target species; however, specimens of D. trachyderma and Z. chilensis were grouped indistinctly within a single clade using 16S and nadh2 fragments. The evolutionary history of Zearaja was also explored, in a broad taxonomic context by using whole mitochondrial genomes (mitogenomes) to understand higher-level phylogenetic relationships among batoids. A data set of 56 mitogenomes of 47 batoids and four outgroups was analysed. Overall, these results showed consensus phylogenomic trees that support previous phyletic reconstructions based on morphological characters, and consequently recovers all extant Orders within the Batoidea in two higher-level reciprocally monophyletic clades: Myliobatiformes + Rhinopristiformes, and Torpediniformes + Rajiformes. Intraspecific divergence is extremely low among the three Zearaja species and may suggest a radiation from a potential ancestral form (Z. chilensis) towards a derived species (Z. maugeana). The evolution of the genus Zearaja could be linked to major geological events, such as the terminal Eocene event and the sinking of Zealandia; which may explain the current restricted geographical distribution to the Southern Hemisphere. Longnose skates in Chilean waters are considered to be a single stock by the fishery management in Chile however, little is known about the level of demographic connectivity within the fishery. Here, population connectivity at five locations along the Chilean coast was explored by using the mitochondrial (control region) and nuclear (microsatellite loci) DNA. Analysis of Z. chilensis populations revealed significant genetic structure among off-shore locations (San Antonio, Valdivia), two locations in the Chiloe Interior Sea (Puerto Montt and Aysen), and Punta Arenas in southern Chile. An important research outcome was lack of connectivity among individuals from the Chiloe Interior Sea and the other two proposed management units. These results provide evidence for three management units for Z. chilensis, and recommendations of separate harvest strategies were made considering each of these units. However, there is no evidence to discriminate the extant population of D. trachyderma as separate management units. This thesis has expanded our general knowledge and has provided management guidelines for sustainable fishery practices in Chile; however, appropriate management and enforcement actions from the Chilean Government are urgently needed to avoid population collapse and extirpation of stocks.
- Research Article
8
- 10.1016/s0187-6236(14)71105-1
- Apr 1, 2014
- Atmósfera
Climate downscaling over southern South America for present-day climate (1970-1989) using the MM5 model. Mean, interannual variability and internal variability
- Research Article
13
- 10.2105/ajph.85.4.546
- Apr 1, 1995
- American Journal of Public Health
This study sought to investigate numerous reports emanating from Punta Arenas, Chile (population 110,000, latitude 53 degrees S), that associated acute ocular and dermatologic disease in humans and animals with excess ultraviolet-B (UV-B) exposure in the setting of the thinning of the ozone column. Ophthalmologic and dermatologic records in Punta Arenas were systematically reviewed to enumerate sentinel diagnoses potentially associated with UV-B exposure, ocular examinations on representative animal populations were performed, and the ambient UV-B exposure in the region during the time of maximal thinning was estimated. No increase in patient visits or conditions attributable to UV-B exposure was seen for periods of known ozone depletion compared with control periods. Although ambient UV-B exposure was 1.6 to 2.3 times the habitual exposure on individual days, this excess exposure conferred only a 1% increase in annual exposure on the region. This study does not support existing lay reports of ocular and dermatologic disease in humans and animals that had been associated with the ozone hole over southern Chile.
- Research Article
1
- 10.1017/s1350482700001390
- Mar 1, 2000
- Meteorological Applications
During 1994/95 a UK Overseas Development Administration (now Department for International Development –DFID) funded project was undertaken to predict ozone amount over Punta Arenas in southern Chile. A low‐cost satellite receiver was installed to receive the digital data stream from the NOAA series of weather satellites. The ozone channel of the TIROS Operational Vertical Sounder instrument on the NOAA satellites was used to obtain maps of stratospheric ozone for the area around Punta Arenas in near real time. Also, a simple model was developed to predict the amount of column ozone from the forecast 100 hPa temperatures obtained from the UK Meteorological Office. These techniques used together made it possible to issue timely warnings to the general public of Punta Arenas before the Antarctic ozone hole moved across southern South America during the Austral spring. Copyright © 2000 Royal Meteorological Society
- Preprint Article
- 10.5194/egusphere-egu21-7474
- Mar 4, 2021
<p>Concentrations of atmospheric ice nucleating particles (INP) were obtained from weekly filter samples which were collected from May 2019 until March 2020 in southern Chile. Sampling took place at an altitude of 620m above sea level, on top of Cerro Mirador, a mountain directly to the west of Punta Arenas (53°S, 71°W). Additional aerosol properties such as particle number size distributions were measured as well. In parallel, ground-based remote sensing measurements with lidar and cloud radar were made in Punta Arenas.</p><p>INP concentrations were obtained from washing atmospheric aerosol particles off from deployed polycarbonate filters and subsequent analysis of the samples on two different freezing arrays which were used and described by us earlier (e.g., in Gong et al., 2019 and Hartmann et al., 2020). INP concentrations could be obtained over a broad temperature range from above -5°C down to -25°C.</p><p>INP concentrations were clearly higher than data obtained for the Southern Ocean region as reported in McCluskey et al. (2018) and Welti et al. (2020). Indeed, they were comparable to concentrations measured at Cape Verde (Gong et al., 2020). INP concentrations obtained during the warm season were spreading over ~ 2 orders of magnitude at any temperature. Data obtained for the cold season almost all were at the upper end of the observed INP concentration range, with only one weekly sample featuring low concentrations.</p><p>Heating of the samples was also applied, and the heated samples had clearly lower INP concentrations across the examined temperatures, implying a biological fraction among the INP of ~ 80%. Therefore, local terrestrial sources may be the source of the observed INP.</p><p>The assumption of local terrestrial sources is strengthened by a case study. For that, two subsequent samples obtained during the cold season were examined in more detail. These were the one sample with low INP concentrations which was obtained during the cold season during the week from August 14 to August 22, and the subsequent sample collected from August 22 to August 29, which was amongst the highest samples. Backward trajectories together with an analysis of Lidar data showed that the low INP concentrations were obtained for a time during which air masses predominantly came in from the south with little contact to land and for calm weather conditions. Conditions were not as stable during the following week which featured air masses mostly coming in from the north-west. The aerosol backscatter coefficient at the height level of the in-situ measurements was obtained from lidar observations for both weeks and shows about 50 % lower aerosol load for the first week, when INP concentrations were low.</p><p>All of this hints to local terrestrial sources for the observed highly ice active biogenic INP.</p><p> </p><p>Literature:</p><p>Gong et al. (2019), Atmos. Chem. Phys., 19, 10883-10900, doi:10.5194/acp-19-10883-2019.</p><p>Gong et al. (2020), Atmos. Chem. Phys., 20, 1451-1468, doi:10.5194/acp-20-1451-2020.</p><p>Hartmann et al. (2020), Geophys. Res. Lett., 47, doi:10.1029/2020GL087770.</p><p>McCluskey et al. (2018), Geophys. Res. Lett., 45, doi:10.1029/2018gl079981.</p><p>Welti et a. (2020), Atmos. Chem. Phys. 20, doi:10.5194/acp-2020-466.</p>
- Research Article
30
- 10.1111/j.1095-8649.2001.tb02316.x
- Jun 1, 2001
- Journal of Fish Biology
Examination of 450 specimens of Macruronus magellanicus from two fishing grounds in southern Chile (Talcahuano: 36°40'S, Punta Arenas: 54° S) revealed 24 205 metazoan parasites, belonging to 15 taxa with low specificity: Chondracanthus australis and Neobrachiella sp. (Copepoda); Elytrophalloides oatesi, Gonocerca phycidis, Derogenes varicus and Brachyphallus parvus, (Digenea); Hepatoxylon trichiuri, Scolex pleuronectis, Clestobothrium crassiceps, Grillotia dollfusi, Pseudophyllidea gen. sp. (Cestoda); Anisakidae, Cucullanus sp. (Nematoda), Corynosoma australe and Acanthocephala gen. sp. (Acanthocephala). The list includes parasites that are common to other merluccids from the zone. The parasitological evidence does not suggest the existence of two discrete stocks, but the existence of a migratory process from south to north.
- Research Article
5
- 10.21475/ajcs.19.13.09.p2031
- Sep 20, 2019
- Australian Journal of Crop Science
Since invasion of Helicoverpa armigera (Hübner) in South America, identification of Helicoverpa species became essential for Integrated Pest Management (IPM). Thus, we worked out on a pictorial key to identify tree important Helicoverpa species that occur in the Southern Cone of America, using new morphological characters from the prothoracic legs. Adult male and female of Helicoverpa zea (Boddie), H. armigera, and Helicoverpa gelotopoeon (Dyar) were used for identification. Prothoracic legs from moths were removed and images were taken (magnification of 25X) with scales and specialized scales. In addition, images (magnification of 50X) of prothoracic legs were used to measure the foretibia and epiphysis. The results showed that measurable characters were more reliable and accurate on male moths than female moths. For this reason, we will show only detailed results of male moths. Foretibia of H. zea were longer than H. gelotopoeon, but shorter than H. armigera. This size is visible with or without scales and specialized scales on males. Here, we show a first detailed description of protibial epiphysis. H. armigera has the longest epiphysis with fore margin pointed and with bristles terminating before the end of epiphysis. This illustrated pictorial key shown some first detailed descriptions of prothoracic legs. These characters are useful on integrated pest management programs of many crops to identify male representatives of Helicoverpa, which are captured on pheromone traps.
- Research Article
6
- 10.5252/cryptogamie-algologie2021v42a1
- Jan 25, 2021
- Cryptogamie, Algologie
Plocamium Lamouroux is a widespread genus for which 45 species are currently recognized. However, classical taxonomy based only on morphological characters, is problematic within this genus. The use of molecular tools has uncovered cryptic genetic species, mistakenly grouped under the name of morphological species that are common and widespread (including the generitype Plocamium cartilagineum (Linnaeus) P.S.Dixon). The aim of this work was to evaluate the species diversity of Plocamium in Southern Chile. For this purpose, three independent molecular markers were sequenced in samples collected from seven populations located between 41°S and 54°S. The species diversity was evaluated using phylogenetic reconstructions and two independent methods for species delimitation (ABGD and GMYC). The outcomes of each method were congruent, suggesting the presence of three species in Southern Chile. One species, named Plocamium sp. 1, is restricted to Punta Guabún, the only locality sampled north of the biogeographic barrier of the 42°S. The other two species, Plocamium sp. 2 and 3 are distributed in sympatry in Patagonia and Tierra del Fuego. The three Chilean species form a clade phylogenetically close to sequences obtained from New Zealand and Australia and a divergence along the coasts of Chile after past transoceanic dispersal is proposed. We propose that divergence in glacial microrefugia could have subsequently happen in the southern part of the coast, this hypothesis being supported by the strong impact of glacial maxima on population dynamics, especially in Plocamium sp. 3.
- Research Article
23
- 10.1080/03014223.2002.9518288
- Jan 1, 2002
- New Zealand Journal of Zoology
A population of “longjaw galaxias”, long known to be present in the Kauru River, a small tributary of the Kakanui River in North Otago, is shown to be a distinct species using both morphological and molecular characters. It is described here as Galaxias cobitinis n. sp., which has: origin of anal fin anterior to that of dorsal fin, only 15 principal caudal fin rays, only 5 pelvic fin rays, and only 51–53 vertebrae. In these and other morphological characters it differs from G. prognathus Stokell. One specimen from the Hakataramea River, lower Waitaki River system appears to also be G. cobitinis. Molecular evidence suggests long isolation from the Kauru River of “true” longjaw galaxias G. prognathus and from rivers draining the high Southern Alps (type locality: Wilberforce River, tributary of the Rakaia River), perhaps dating back as long as 11–4 million years ago (late Miocene‐early Pliocene). This prolonged isolation contrasts with hypothesised more recent isolation of populations of the Galaxias vulgaris species group in the Kakanui River from other populations of that species group. Thus, sympatric species of Galaxias have contrasting biogeographic histories in the Kakanui River.
- Peer Review Report
- 10.5194/acp-2021-1097-rc1
- Feb 9, 2022
Record-breaking wildfires raged in southeastern Australia in late December 2019 and early January 2020. Rather strong pyrocumulonimbus (pyroCb) convection developed over the fire areas and lifted enormous amounts of biomass-burning smoke into the tropopause region and caused the strongest wildfire-related stratospheric aerosol perturbation ever observed around the globe. We discuss the geometrical, optical, and microphyscial properties of the stratospheric smoke layers and the decay of this major stratospheric perturbation. A multiwavelength polarization Raman lidar at Punta Arenas (53.2° S, 70.9° W), southern Chile, and an elastic-backscatter Raman lidar at Río Grande (53.8° S, 67.7° W) in southern Argentina were operated to monitor the major record-breaking event until the end of 2021. These lidar measurements can be regarded as representative for mid to high latitudes in the Southern Hemisphere. A unique dynamical feature, an anticyclonic, smoke-filled vortex with 1000 km horizontal width and 5 km vertical extent, which ascended by about 500 m per day, was observed over the full last week of January 2020. The key results of the long-term study are as follows: The smoke layers extended, on average, from 9 to 24 km in height. The smoke partly ascended to more than 30 km height as a result of self-lifting processes. Clear signs of a smoke impact on the record-breaking ozone hole over Antarctica in September–November 2020 were found. A slow decay of the stratospheric perturbation detected by means of the 532 nm aerosol optical thickness (AOT) yielded an e-folding decay time of 19–20 months. The maximum smoke AOT was around 1.0 over Punta Arenas in January 2020 and thus two to three orders of magnitude above the stratospheric aerosol background of 0.005. After two months with strongly varying smoke conditions, the 532 nm AOT decreased to 0.03–0.06 from March–December 2020 and to 0.015–0.03 throughout 2021. The particle extinction coefficients were in the range of 10–75 Mm−1 in January 2020, and later on mostly between 1 and 5 Mm−1. Combined lidar-photometer retrievals revealed typical smoke extinction-to-backscatter ratios of 69 ±19 sr (at 355 nm), 91 ± 17 sr (at 532 nm), and 120 ± 22 sr (at 1064 nm). An ozone reduction of 20–25 % in the 15–22 km height range was observed over Antarctic and New Zealand ozonesonde stations in the smoke-polluted air with particle surface area concentrations of 1–5 μm2 cm−3.
- Research Article
18
- 10.1371/journal.pone.0172255
- Feb 16, 2017
- PloS one
The longnose skates (Zearaja chilensis and Dipturus trachyderma) are the main component of the elasmobranch fisheries in the south-east Pacific Ocean. Both species are considered to be a single stock by the fishery management in Chile however, little is known about the level of demographic connectivity within the fishery. In this study, we used a genetic variation (560 bp of the control region of the mitochondrial genome and ten microsatellite loci) to explore population connectivity at five locations along the Chilean coast. Analysis of Z. chilensis populations revealed significant genetic structure among off-shore locations (San Antonio, Valdivia), two locations in the Chiloé Interior Sea (Puerto Montt and Aysén) and Punta Arenas in southern Chile. For example, mtDNA haplotype diversity was similar across off-shore locations and Punta Arenas (h = 0.46–0.50), it was significantly different to those in the Chiloé Interior Sea (h = 0.08). These results raise concerns about the long-term survival of the species within the interior sea, as population resilience will rely almost exclusively on self-recruitment. In contrast, little evidence of genetic structure was found for D. trachyderma. Our results provide evidence for three management units for Z. chilensis, and we recommend that separate management arrangements are required for each of these units. However, there is no evidence to discriminate the extant population of Dipturus trachyderma as separate management units. The lack of genetic population subdivision for D. trachyderma appears to correspond with their higher dispersal ability and more offshore habitat preference.
- Research Article
36
- 10.1067/mjd.2002.118556
- Feb 1, 2002
- Journal of the American Academy of Dermatology
Increase in sunburns and photosensitivity disorders at the edge of the Antarctic ozone hole, Southern Chile, 1986-2000
- Research Article
28
- 10.5194/acp-22-7417-2022
- Jun 9, 2022
- Atmospheric Chemistry and Physics
Abstract. Record-breaking wildfires raged in southeastern Australia in late December 2019 and early January 2020. Rather strong pyrocumulonimbus (pyroCb) convection developed over the fire areas and lofted enormous amounts of biomass burning smoke into the tropopause region and caused the strongest wildfire-related stratospheric aerosol perturbation ever observed around the globe. We discuss the geometrical, optical, and microphysical properties of the stratospheric smoke layers and the decay of this major stratospheric perturbation. A multiwavelength polarization Raman lidar at Punta Arenas (53.2∘ S, 70.9∘ W), southern Chile, and an elastic backscatter Raman lidar at Río Grande (53.8∘ S, 67.7∘ W) in southern Argentina, were operated to monitor the major record-breaking event until the end of 2021. These lidar measurements can be regarded as representative for mid to high latitudes in the Southern Hemisphere. A unique dynamical feature, an anticyclonic, smoke-filled vortex with 1000 km horizontal width and 5 km vertical extent, which ascended by about 500 m d−1, was observed over the full last week of January 2020. The key results of the long-term study are as follows. The smoke layers extended, on average, from 9 to 24 km in height. The smoke partly ascended to more than 30 km height as a result of self-lofting processes. Clear signs of a smoke impact on the record-breaking ozone hole over Antarctica in September–November 2020 were found. A slow decay of the stratospheric perturbation detected by means of the 532 nm aerosol optical thickness (AOT) yielded an e-folding decay time of 19–20 months. The maximum smoke AOT was around 1.0 over Punta Arenas in January 2020 and thus 2 to 3 orders of magnitude above the stratospheric aerosol background of 0.005. After 2 months with strongly varying smoke conditions, the 532 nm AOT decreased to 0.03-0.06 from March–December 2020 and to 0.015–0.03 throughout 2021. The particle extinction coefficients at 532 nm were in the range of 10–75 Mm−1 in January 2020 and, later on, mostly between 1 and 5 Mm−1. Combined lidar–photometer retrievals revealed typical smoke extinction-to-backscatter ratios of 69 ± 19 sr (at 355 nm), 91 ± 17 sr (at 532 nm), and 120 ± 22 sr (at 1064 nm). An ozone reduction of 20 %–25 % in the 15–22 km height range was observed over Antarctica and New Zealand ozonesonde stations in the smoke-polluted air, with particle surface area concentrations of 1–5 µm2 cm−3.
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