The value of idiosyncratic markers and changes to conserved tRNA sequences from the mitochondrial genome of hard ticks (Acari: Ixodida: Ixodidae) for phylogenetic inference

Idiosyncratic markers are features of genes and genomes that are so unusual that it is unlikely that they evolved more than once in a lineage of organisms. Here we explore further the potential of idiosyncratic markers and changes to typically conserved tRNA sequences for phylogenetic inference. Hard ticks were chosen as the model group because their phylogeny has been studied extensively. Fifty-eight candidate markers from hard ticks ( family Ixodidae) and 22 markers from the subfamily Rhipicephalinae sensu lato were mapped onto phylogenies of these groups. Two of the most interesting markers, features of the secondary structure of two different tRNAs, gave strong support to the hypothesis that species of the Prostriata ( Ixodes spp.) are monophyletic. Previous analyses of genes and morphology did not strongly support this relationship, instead suggesting that the Prostriata is paraphyletic with respect to the Metastriata ( the rest of the hard ticks). Parallel or convergent evolution was not found in the arrangements of mitochondrial genes in ticks nor were there any reversals to the ancestral arthropod character state. Many of the markers identified were phylogenetically informative, whereas others should be informative with study of additional taxa. Idiosyncratic markers and changes to typically conserved nucleotides in tRNAs that are phylogenetically informative were common in this data set, and thus these types of markers might be found in other organisms.

Notes on the biology of Amblyomma dissimile Kock, 1844 (Acari: Ixodida) on Bufo marinus (Linnaeus, 1758) from Brazil

Amblyomma dissimile is a common ectoparasite of cold blooded animals and is an accidental ectoparasite of some wild mammals. Details of the biology of specimens from the State of Amapá were studied in the laboratory in a humidity chamber at an average environmental temperature of 19.5 °C, using Bufo marinus as host for the time in Brazil. We also report the first record of this species in the State of Minas Gerais.

A review of the ticks (Acari, Ixodida) of Brazil, their hosts and geographic distribution - 1. The State of Rio Grande do Sul, Southern Brazil

A review of the ticks (Acari, Ixodida) of the State of Rio Grande do Sul, southern Brazil, was completed as a step towards a definitive list (currently indicated as 12) of such species, their hosts and distribution. The ticks: Argas miniatus (poultry), Ixodes loricatus (opossums), Amblyomma aureolatum (dogs), A. calcaratum (anteaters), A. cooperi (capybaras), A. nodosum (anteaters), A. tigrinum (dogs) (Neotropical) and Rhipicephalus sanguineus (dogs) (introduced, cosmopolitan, Afrotropical) were confirmed as present, in addition to the predominant, Boophilus microplus (cattle) (introduced, pan-tropical, Oriental). Of the further 18 species thus far reported in the literature as present in the state, but unavailable for examination: only Ornithodoros brasiliensis (humans and their habitations) (Neotropical), Ixodes affinis (deer) (Nearctic/Neotropical) and I. auritulus (birds) (Nearctic/Neotropical/Afrotropical/ Australasian) are considered likely; 13 species would benefit from corroborative local data but the majority appear unlikely; reports of A. maculatum (Nearctic/Neotropical, but circum-Caribbean) are considered erroneous; the validity of A. fuscum is in doubt. The very recent, first known report of the tropical Anocentor nitens (horses)(Nearctic/Neotropical), but still apparent absence of the tropical A. cajennense (catholic) (Nearctic/Neotropical) and the sub-tropical/temperate Ixodes pararicinus (cattle) (Neotropical) in Rio Grande do Sul are important for considerations on their current biogeographical distribution and its dynamics in South America. The state has relatively long established, introduced ("exotic"), Old World tick species (B. microplus, R. sanguineus) that continue to represent significant pests and disease vectors to their traditional, introduced domestic animal hosts, cattle and urban dogs. There are also indigenous, New World ticks (A. miniatus, O. brasiliensis, A. aureolatum, A. nitens), as both long established and possibly newly locally introduced species in the state, that should be considered as potential and emergent pests and pathogen vectors to humans and their more recently acquired, introduced domestic animal hosts; rural poultry, dogs and horses.

Ornithodoros guaporensis (Acari, Ixodida: Argasidae), a new tick species from the Guaporé River Basin in the Bolivian Amazon

The soft tick Ornithodoros guaporensis n. sp. (Acari: Ixodida: Argasidae) is described from larvae and adults. Morphological analysis and 16S rDNA sequences are provided. Adults were collected from a rocky fissure inhabited by bats located in the Amazonian forest in north-eastern Bolivia (Beni Department) close to the Guaporé River. Larvae were obtained from eggs laid by females collected in the field, and which were fed on rabbits in the laboratory. Larvae of O. guaporensis are morphologically closely related to Ornithodoros rioplatensis, Ornithodoros puertoricensis and Orni-thodoros talaje. Larvae of O. guaporensis and O. rioplatensis can be separated from O. puertoricensis and O. talaje by the number of pairs of dorsal setae (20 in O. guaporensis and O. rioplatensis, 18 in O. puertoricensis and 17 in O. talaje). Larvae of O. guaporensis and O. rioplatensis can be differentiated by the medial dental formula (2/2 in O. guaporensis and 3/3 in O. rioplatensis) and the apex of the hypostome, which is more pointed in O. rioplatensis than in O. guaporensis. The Principal Component Analysis performed with morphometric characters of larvae showed a clear separation among O. guaporensis, O. rioplatensis, O. puertoricensis and O. talaje. Significant morphological differences among adults of these four species were not found. The analysis of the 16S rDNA sequences allowed for the differentiation between O. guaporensis and the remaining Neotropical species of the family Argasidae.

Taxonomic and phylogenetic relationships between neotropical species of ticks from genus Amblyomma (Acari: Ixodidae) inferred from second internal transcribed spacer sequences of rDNA

The accurate specific identification of ticks is essential for the study, control and prevention of tick-borne diseases. Herein, we determined ribosomal nucleotide sequences of the second internal transcribed spacer (ITS2) of 15 Neotropical hard tick species of the genus Amblyomma Koch found in Brazil. Most of the studied ticks accidentally parasite humans and potentially act as vectors of zoonoses. Lengths of the ITS2 sequences ranged from 956 to 1,207 bp, whereas GC content varied from 62.4 to 66.9%. A matrix of ITS2 divergence was calculated with the ITS2 sequence data obtained showing divergence levels varying from 1.5 to 28.8%. The analysis indicated that this molecular marker can be useful for Amblyomma-specific identification. Phylogenetic inferences based on the ITS2 sequences were used to assess some issues in subgenus taxonomy. © 2007 Entomological Society of America.

Neurotoxic action of permethrin in Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) female ticks. Morphological and cytochemical evaluation of the central nervous system

Studies on the molecular bases of the neurotoxic action of acaricides are found in the literature; but there are no studies of this action on the nervous system of ticks at the cellular level. The present study describes the morphological and cytochemical changes in the synganglion of Rhipicephalus sanguineus semi-engorged females exposed to different concentrations of permethrin, a pyrethroid with recognized neurotoxic action. Permethrin induced the degeneration of the synganglion through a process of apoptosis involving autophagy, characterized by the condensation and margination of the chromatin, formation of blebs in the nuclear envelope and fragmentation of the nucleus, loss of shape of neural cells and integrity of cellular membrane, cytoplasmic shrinkage, and lower levels of acid phosphatase in the nervous tissue as the concentration of permethrin increased. This study provided further evidence of the neurotoxic action of permethrin, which impairs the metabolism of R. sanguineus nervous systems, and consequently the physiology of other systems, dependent on the neural control. These results provide cytochemical and histological confirmation of the neurotoxic action of permethrin, previously inferred from molecular and tick behavioral evidence. © 2013 Elsevier B.V.

Action of andiroba oil and permethrin on the central nervous and reproductive systems of Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) ticks females. A confocal study

Research for acaricides with lower toxicity and impact on the environment has been intensified. An alternative would be the use of natural compounds or of synthetic products in lower concentrations than the ones sold commercially. Thus, this study describes the action of andiroba seed oil on the nuclei of the ovary and synganglion cells of Rhipicephalus sanguineus, and presents an analysis of the nuclear morphology of the nervous system cells of this tick species when exposed to permethrin. The results obtained showed that, although no changes have been observed in the genetic material of the ovary cells exposed to the andiroba oil, this compound, as well as permethrin, has neurotoxic action on the females of this species. The damages caused to the physiology of the synganglion, due to the loss of integrity of the genetic material, would result in the impairment of the metabolism of other systems of R. sanguineus ticks. © 2013 Elsevier Ltd.

Comparative analysis of spermatids of Rhipicephalus sanguineus sensu lato (Ixodidae) and Ornithodoros rostratus ticks (Argasidae): morphophysiology aimed at systematics

The phylogenetic relationships among tick species (Acari: Ixodida) have been revisited by several researchers over the last decades. Two subfamilies, Rhipicephalinae (Ixodidae) and Ornithodorinae (Argasidae), deserve special attention. The male reproductive system morphology, as well as the ultrastructure of the germ cells, may provide important information for phylogeny and systematics of metazoan groups, with spermatozoa exhibiting characters that can be used for this purpose. With that information in mind, this study aimed at evaluating, through a comparative analysis, the morphology of the male reproductive systems and germ cells of ticks species Rhipicephalus sanguineus and Ornithodoros rostratus. In order to do that, histology and scanning electron microscopy techniques were used. The results have shown that despite the similarities in the general morphology of the male reproductive system among studied Ixodida so far, there are morphological differences among the species studied herein, mainly the U-shaped testis (ancestral character) in O. rostratus and the pair testes (derived character) in R. sanguineus, and the general morphology of germ cells (spermatids V). Besides that, the morphological changes observed during the spermiogenesis appear to be different between the species studied here, probably characterizing the two families considered. The data generated in this study showed the importance of comparative internal morphology studies, mainly in regard to spermatology, despite the morphological data obtained herein not being enough to product a cladogram (sperm cladistics), it was already possible to observe clear differences among families Argasidae and Ixodidae in regard to the organization of their male reproductive systems and concerning the external morphology of spermatids. Data yet to be obtained through transmission electron microscopy techniques will allow the application of spermiocladistics and spermiotaxonomy as tools for tick systematics.

Rickettsial Infection in Ticks Collected from Road-Killed Wild Animals in Rio de Janeiro, Brazil

During 2008D2010, ticks were collected from road-killed wild animals within the Serra dos Orgaos National Park area in the state of Rio de Janeiro, Brazil. In total, 193 tick specimens were collected, including Amblyomma dubitatum Neumann and Amblyomma cajennense (F.) from four Hydrochoerus hydrochaeris (L.), Amblyomma calcaratum Neumann and A. cajennense from four Tamandua tetradactyla (L.), Amblyomma aureolatum (Pallas) and A. cajennense from five Cerdocyon thous L., Amblyomma longirostre (Koch) from one Sphiggurus villosus (Cuvier), Amblyomma varium Koch from three Bradypus variegatus Schinz, and A. cajennense from one Buteogallus meridionalis (Latham). Molecular analyses based on polymerase chain reaction targeting two rickettsial genes (gltA and ompA) on tick DNA extracts showed that 70.6% (12/17) of the A. dubitatum adult ticks, and all Amblyomma sp. nymphal pools collected from capybaras were shown to contain rickettsial DNA, which after DNA sequencing, revealed to be 100% identical to the recently identified Rickettsia sp. strain Pampulha from A. dubitatum ticks collected in the state of Minas Gerais, Brazil. Phylogenetic analysis with concatenated sequences (gltA-ompA) showed that our sequence from A. dubitatum ticks, referred to Rickettsia sp. strain Serra dos Orgaos, segregated under 99% bootstrap support in a same cluster with Old World rickettsiae, namely R. tamurae, R. monacensis, and Rickettsia sp. strain 774e. Because A. dubitatum is known to bite humans, the potential role of Rickettsia sp. strain Serra dos Orgaos as human pathogen must be taken into account, because both R. tamurae and R. monacencis have been reported infecting human beings.

New reports of Antricola guglielmonei and Antricola delacruzi in Brazil, and a description of a new argasid species (Acari)

Adults of 3 tick species (Acari: Argasidae) identified as Antricola guglielmonei, Antricola delacruzi, and Carios rondoniensis n. sp. were collected oil bill guano in a cave in the state of Rondonia, western Amazon. Brazil. Adults of C. rondoniensis Possess a unique combination of characters that distinguish them front all described adults in the Argasidae. i.e.. a large spiracular plate densely filled with small goblets, a well-developed flap covering the female genital opening, and palpi containing several tufts of long setae oil articles 2 and 3. Unlike Ornithodoros or other Carios species. adults of C rondoniensis have a scooplike hypostome devoid of denticles, as in Antricola spp. Conversely, the presence of a pair of long posthypostomal setae, and a slitlike transverse fissure at the Capsule opening of the Haller's organ, are characters of C. rondonensis that are also found ill species of Carios and Ornithodoros, but not in Antricola species. Molecular analyses inferred from a portion of the 16S rRNA mitochondrial gene indicate that C. rondoniensis is phylogenetically closest to species of Carios. followed by species of Antricola. and then Ornithodoros. Because the highest bootstrap value linking C. rondoniensis to Carios spp. was 62%, further phylogenetic studies are needed to better evaluate the taxonomic Status of the former species.

Carios mimon (Acari: Argasidae): description of adults and redescription of larva

Carios mimon is an argasid tick common on Chiroptera, originally described from larvae collected on bats Mimon crenulatum from Bolivia and Eptesicus brasiliensis from Uruguay. Later it was also registered from Argentina and recently included among the Brazilian tick fauna. In Brazil, this species is very aggressive to man, resulting in intense inflammatory response and pain. It is known only by the larval description and its morphology resembles that from other species currently included into the genus Carios, formerly classified into the subgenus Alectorobius, genus Ornithodoros. Here we describe adults and redescribe the larva of C. mimon, based on light and scanning electron microscopy. Remarks about its morphological similarity with other species of this genus are also discussed. Molecular analysis inferred from a portion of the 16S rRNA mitochondrial gene placed C. mimon in a cluster supported by maximal bootstrap value (100%) with other argasid species (mostly bat parasites in the New World), which have been classified into either the genus Ornithodoros or Carios, depending on the Argasidae classification adopted by different authors.

Carios fonsecai sp nov (Acari, Argasidae), a bat tick from the central-western region of Brazil

Males, females, and larvae of Carios fonsecai sp. nov. are described from free-living ticks collected in a cave at Bonito, state of Mato Grosso do Sul, Brazil. The presence of cheeks and legs with micromammillate cuticle makes adults of C. fonsecai morphologically related to a group of argasid species (mostly bat-associated) formerly classified into the subgenus Alectorobius, genus Ornithodoros. Examination of larvae indicates that C. fonsecai is clearly distinct from most of the previously described Carios species formerly classified into the subgenus Alectorobius, based primarily on its larger body size, dorsal setae number, dorsal plate shape, and hypostomal morphology. On the other hand, the larva of C. fonsecai is most similar to Carios peropteryx, and Carios peruvianus, from which differences in dorsal plate length and width, tarsal setae, and hypostome characteristics are useful for morphological differentiation. The mitochondrial 16S rDNA sequence of C. fonsecai showed to be closest (85-88% identity) to several corresponding sequences of different Carios species available in GenBank. Bats identified as Peropteryx macrotis and Desmodus rotundus were found infested by C. fonsecai larvae in the same cave where the type series was collected. C. fonsecai showed to be aggressive to humans in the laboratory.

A new subfamily, Bothriocrotoninae n. subfam., for the genus Bothriocroton Keirans, King & Sharrad, 1994 status amend. (Ixodida : Ixodidae), and the synonymy of Aponomma Neumann, 1899 with Amblyomma Koch, 1844

Evidence suggesting polyphyly of the traditionally recognised tick genus Aponomma Neumann, 1899 is summarized. Continued recognition of this genus in its current concept leaves a polyphyletic genus Aponomma and a paraphyletic genus Amblyomma Koch, 1844. To improve the correlation between our understanding of phylogenetic relationships in metastriate ticks and their classification, a few changes in classification are proposed. The members of the 'indigenous Australian Aponomma' group (sensu Kaufman, 1972), A. auruginans Schulze, 1936, A. concolor Neumann, 1899, A. glebopalma Keirans, King & Sharrad, 1994, A. hydrosauri (Denny, 1843) and A. undatum (Fabricius, 1775), are transferred to Bothriocroton Keirans, King & Sharrad, 1994, which is raised to full generic rank. The remaining members of Aponomma are transferred to Amblyomma. Uncertainty remains on relationships of Bothriocroton to other metastriate lineages and on the systematic position of the two species formerly included in the 'primitive Aponomma' group, A. elaphense Price, 1959 and A. sphenodonti Dumbleton, 1943.

Ecological analysis of Acari recovered from coprolites from archaeological site of Northeast Brazil

Coprolite samples of human and animal origin from the excavations performed at the archaeological site of Furna do Estrago, at Brejo da Madre de Deus in the state of Pernambuco, Brazil and sent to the Paleoparasitology Laboratory at Escola Nacional de Saúde Pública-Fiocruz, Rio de Janeiro, were analyzed for mites. After rehydratation and sedimentation of the coprolites, the alimentary contents and the sediments were examined and the mites collected and prepared in definitive whole mounts, using Hoyer's medium. Mites of the following suborders and orders were recovered: suborder Acaridia; order Gamasida; order Ixodida with the familiy Ixodidae (Ixodes sp. and Amblyomma sp. larvae, scutum, idiosoma, gnathosoma); order Oribatida (Aphelacarus sp., Apolohmannia sp., Eophypochthonius sp., Cosmochthonius sp., Pterobates sp., Poronoticae with pteromorphae not auriculate); order Astigmata with the families Atopomelidae (Chirodiscoides caviae), Anoetidae hypopus, Acaridae (Suidasia pontifica), Glycyphagidae (Blomia tropicalis), Pyroglyphidae (Hirstia passericola); order Actinedida with the family Tarsonemidae (Iponemus radiatae). The present work discusses the possibility of the preservation of the mite groups found up to the present day. We also discuss their relationship with the environment and their importance to present populations.