The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform
Stephen C Barker - One of the best experts on this subject based on the ideXlab platform.
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a list of the 70 species of australian ticks diagnostic guides to and species accounts of ixodes holocyclus paralysis tick ixodes cornuatus southern paralysis tick and rhipicephalus australis australian cattle tick and consideration of the place of a
International Journal for Parasitology, 2014Co-Authors: Stephen C Barker, A R Walker, Dayana CampeloAbstract:Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites).
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relationships among the three major lineages of the acari arthropoda arachnida inferred from small subunit rrna paraphyly of the parasitiformes with respect to the opilioacariformes and relative rates of nucleotide substitution
Invertebrate Systematics, 2005Co-Authors: Anna Murrell, David Evans Walter, Susan J Dobson, Nick J H Campbell, Renfu Shao, Stephen C BarkerAbstract:We inferred phylogeny among the three major lineages of the Acari ( mites) from the small subunit rRNA gene. Our phylogeny indicates that the Opilioacariformes is the sister-group to the Ixodida+Holothyrida, not the Ixodida+Mesostigmata+Holothyrida, as previously thought. Support for this relationship increased when sites with the highest rates of nucleotide substitution, and thus the greatest potential for saturation with nucleotide substitutions, were removed. Indeed, the increase in support ( and resolution) was despite a 70% reduction in the number of parsimony-informative sites from 408 to 115. This shows that rather than 'noisy' sites having no impact on resolution of deep branches, 'noisy' sites have the potential to obscure phylogenetic relationships. The arrangement, Ixodida+Holothyrida+Opilioacariformes, however, may be an artefact of long-branch attraction since relative-rate tests showed that the Mesostigmata have significantly faster rates of nucleotide substitution than other parasitiform mites. Thus, the fast rates of nucleotide substitution of the Mesostigmata might have caused the Mesostigmata to be attracted to the outgroup in our trees. We tested the hypothesis that the high rate of nucleotide substitution in some mites was related to their short generation times. The Acari species that have high nucleotide substitution rates usually have short generation times; these mites also tend to be more active and thus have higher metabolic rates than other mites. Therefore, more than one factor may affect the rate of nucleotide substitution in these mites.
Dayana Campelo - One of the best experts on this subject based on the ideXlab platform.
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a list of the 70 species of australian ticks diagnostic guides to and species accounts of ixodes holocyclus paralysis tick ixodes cornuatus southern paralysis tick and rhipicephalus australis australian cattle tick and consideration of the place of a
International Journal for Parasitology, 2014Co-Authors: Stephen C Barker, A R Walker, Dayana CampeloAbstract:Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites).
J.h. Oliver - One of the best experts on this subject based on the ideXlab platform.
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systematic relationships in the soft ticks acari ixodida argasidae
Systematic Entomology, 1993Co-Authors: J.s.h. Klompen, J.h. OliverAbstract:Abstract. A phylogenetic analysis of relationships at the generic to subgeneric level is carried out for the family Argasidae. The analysis is based on a total of eighty-three characters drawn from larval and adult body and leg morphology, Haller's organ morphology, development and behaviour. These characters are polarized by comparison with representatives of the families Ixodidae and Nuttalliellidae (both suborder Ixodida), and the suborders Holothyrida and Mesostigmata. A total of two equally most parsimonious trees was generated after successive approximations character weighting. Although the support for some lineages in these trees is not very strong, they provide a substantially better overall fit to the data than any of the hypotheses derived from existing classifications of the family. The classification of the Argasidae is revised to reflect the results of the phylogenetic analysis, and compared to existing classifications employed by Eastern European (‘Soviet’) and American authors. The subfamily Argasinae sens.n. contains one genus, Argas sens.n., with five subgenera, A.(Argas) sens.n. [including A.(Persicargas)syn.n.], A.(Secretargas), A.(Ogadenus), A.(Proknekalia)comb.n. and A.(Alveonasus)comb.n. The latter two subgenera (latter three in the Soviet classification) are transferred from the Ornithodorinae, where they were classified as subgenera of Ornithodoros (American school) or Alveonasus (Soviet school). The Ornithodorinae sens.n. consists of three genera, Ornithodoros sens.n., Otobius sens.n. and Carios stat.n. [raised from Argas (Carios)]. The genus Ornithodoros includes the previously recognized subgenera Ornithodoros (Pavlovskyella), O.(Ornamentum) and Argas (Microargas), all syn.n., while Otobius is expanded to include Ornithodoros sparnuscomb.n. The genus Carios contains nearly all bat-associated argasids, including the previously recognized genera Antricola and Nothoaspis, and subgenera Argas (Chiropterargas), Ornithodoros (Alectorobius), O.(Reticulinasus) and O.(Subparmatus), all syn.n. The available evidence does not allow recognition of subgenera in the genera Ornithodoros, Otobius or Carios. Summary A phylogenetic analysis of relationships in the Argasidae based on a wide variety of characters drawn from all life stages generated two highly similar and relatively well corroborated hypotheses of relationships. These hypotheses provide a much better fit to the data than phylogenies derived from existing, traditional classifications, and are used as the basis for a revision of the classification within the Argasidae. Although this classification has its weaknesses, e.g. the relatively poor support for Ornithodoros, Carios and Argas (Secretargas), it is considered superior to traditional classifications not only because of the superior fit to the data, but also because it recognizes only monophyletic taxa. In addition, by abandoning the more or less typological approach traditional in argasid systematics in favour of a lineage approach, it allows the explicit recognition of affinities for all taxa, including unusual forms such as Argas (Alveonasus) cooleyi, Ornithodoros transversus, O.elongatus, Otobius megnini, O.lagophilus, O.sparnus, Carios rudis and C.reddelli.
J.s.h. Klompen - One of the best experts on this subject based on the ideXlab platform.
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systematic relationships in the soft ticks acari ixodida argasidae
Systematic Entomology, 1993Co-Authors: J.s.h. Klompen, J.h. OliverAbstract:Abstract. A phylogenetic analysis of relationships at the generic to subgeneric level is carried out for the family Argasidae. The analysis is based on a total of eighty-three characters drawn from larval and adult body and leg morphology, Haller's organ morphology, development and behaviour. These characters are polarized by comparison with representatives of the families Ixodidae and Nuttalliellidae (both suborder Ixodida), and the suborders Holothyrida and Mesostigmata. A total of two equally most parsimonious trees was generated after successive approximations character weighting. Although the support for some lineages in these trees is not very strong, they provide a substantially better overall fit to the data than any of the hypotheses derived from existing classifications of the family. The classification of the Argasidae is revised to reflect the results of the phylogenetic analysis, and compared to existing classifications employed by Eastern European (‘Soviet’) and American authors. The subfamily Argasinae sens.n. contains one genus, Argas sens.n., with five subgenera, A.(Argas) sens.n. [including A.(Persicargas)syn.n.], A.(Secretargas), A.(Ogadenus), A.(Proknekalia)comb.n. and A.(Alveonasus)comb.n. The latter two subgenera (latter three in the Soviet classification) are transferred from the Ornithodorinae, where they were classified as subgenera of Ornithodoros (American school) or Alveonasus (Soviet school). The Ornithodorinae sens.n. consists of three genera, Ornithodoros sens.n., Otobius sens.n. and Carios stat.n. [raised from Argas (Carios)]. The genus Ornithodoros includes the previously recognized subgenera Ornithodoros (Pavlovskyella), O.(Ornamentum) and Argas (Microargas), all syn.n., while Otobius is expanded to include Ornithodoros sparnuscomb.n. The genus Carios contains nearly all bat-associated argasids, including the previously recognized genera Antricola and Nothoaspis, and subgenera Argas (Chiropterargas), Ornithodoros (Alectorobius), O.(Reticulinasus) and O.(Subparmatus), all syn.n. The available evidence does not allow recognition of subgenera in the genera Ornithodoros, Otobius or Carios. Summary A phylogenetic analysis of relationships in the Argasidae based on a wide variety of characters drawn from all life stages generated two highly similar and relatively well corroborated hypotheses of relationships. These hypotheses provide a much better fit to the data than phylogenies derived from existing, traditional classifications, and are used as the basis for a revision of the classification within the Argasidae. Although this classification has its weaknesses, e.g. the relatively poor support for Ornithodoros, Carios and Argas (Secretargas), it is considered superior to traditional classifications not only because of the superior fit to the data, but also because it recognizes only monophyletic taxa. In addition, by abandoning the more or less typological approach traditional in argasid systematics in favour of a lineage approach, it allows the explicit recognition of affinities for all taxa, including unusual forms such as Argas (Alveonasus) cooleyi, Ornithodoros transversus, O.elongatus, Otobius megnini, O.lagophilus, O.sparnus, Carios rudis and C.reddelli.
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comparative morphology of argasid larvae acari ixodida argasidae with notes on phylogenetic relationships
Annals of The Entomological Society of America, 1992Co-Authors: J.s.h. KlompenAbstract:A comparative analysis of larval morphology in the Argasidae was conducted, emphasizing the setation of the appendages. Larvae of 76 argasid species, including one or more representatives of all nominal genera and subgenera, were examined and compared with larval and nymphal Ixodidae, Holothyrida, and Mesostigmata (Parasitiformes). Between-species variation in the setation pattern of the appendages is considerable, whereas within-species variability is low. All of the observed variation in setal patterns can be explained as the result of ontogenetic shifts, including both accelerations and delayed additions. Hypotheses of homology for most palpal and leg setae are established based on ontogenetic and comparative evidence. A preliminary analysis of relationships, based on larval characters only, suggests that all bat-associated taxa in the genera Argas and Ornithodoros are part of a monophyletic lineage including the genus Antricola (and possibly Nothoaspis ), the subgenus Argas (Microargas) is more closely related to the subgenus Ornithodoros (s.s.) than to any of the subgenera in Argas , and the subgenera Ornithodoros (Alveonasus), Ornithodoros (Proknekalia), Argas (Ogadenus), and Argas (Secretargas) form a monophyletic group (resembling the genus Alveonasus sensu Filippova 1966). The established genera Argas and Ornithodoros do not appear to be natural groups, but modifications of existing classifications of the Argasidae are delayed until characters from the postlarval stages can be integrated in the systematic analysis.
A R Walker - One of the best experts on this subject based on the ideXlab platform.
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a list of the 70 species of australian ticks diagnostic guides to and species accounts of ixodes holocyclus paralysis tick ixodes cornuatus southern paralysis tick and rhipicephalus australis australian cattle tick and consideration of the place of a
International Journal for Parasitology, 2014Co-Authors: Stephen C Barker, A R Walker, Dayana CampeloAbstract:Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites).