Bothriocroton oudemansi (Neumann, 1910) n. comb. (Acari: Ixodida: Ixodidae), an ectoparasite of the western long-beaked echidna in Papua New Guinea: redescription of the male and first description of the female and nymph.

Specimens of Amblyomma oudemansi (Neumann, 1910) were collected in Papua New Guinea from an endangered monotreme, Zaglossus bruijni (Peters & Doria), the western long-beaked echidna. These ticks were compared morphologically and molecularly with species formerly assigned to Aponomma Neumann, 1899 (now included in Bothriocroton Keirans, King, & Sharrad, 1994 or Amblyomma Koch, 1844), and a phylogeny was generated. Based on our results, we reassign this tick to Bothriocroton, as B. oudemansi (Neumann, 1910) n. comb. Original descriptions are provided for the female and the nymph of this species and the male is redescribed. A revised list of all Bothriocroton records and holdings in the US National Tick Collection is also provided.

First U.S. record of the hard tick Ixodes (Pholeoixodes) gregsoni Lindquist, Wu, and Redner.

Ixodes (Pholeoixodes) gregsoni Lindquist, Wu, and Redner, a species of hard tick described in 1999 in Canada, was recovered from a harvested fisher (Martes pennanti Erxleben) and a domestic cat (Felis silvestris catus Ragni and Randi) in Vermont in 2001 and from harvested mink (Mustela vison Schreber) in Maine in 2003. These samples are the first records of this species within the United States. Although knowledge of this tick's natural history and distribution are still preliminary, these records indicate a possible greater distribution for I. gregsoni than initially perceived. Although its status as a disease vector is presently unknown, natural resource professionals should be aware of the possibility of this tick's occurrence in the northeastern United States.

Distribution, seasonality, and hosts of the Rocky Mountain wood tick in the United States.

Anaplasma marginale Theiler is a tick-borne pathogen that causes anaplasmosis in cattle. There are approximately 20 tick species worldwide that are implicated as vectors of this pathogen. In the United States, Dermacentor andersoni Stiles and Dermacentor variabilis (Say) are the principal vectors. The risk of transmission of anaplasmosis to cattle has been largely based on the distribution of D. andersoni in the United States. We developed a centralized geographic database that incorporates collection records for D. andersoni from two large national databases. We reviewed the geographic records in each database and postings from MEDLINE and AGRICOLA to produce a national county-level distribution map based on a total of 5,898 records. The records spanned the period from 1903 through 2001 with the majority between 1921 to 1940. Populations of D. andersoni were recorded from 267 counties in 14 states and were distinguished as either established or reported. We found 180 counties with established populations of D. andersoni and 87 counties with reported occurrences in 14 states with the majority of established populations reported from Montana, Idaho, and Oregon. D. andersoni populations in the United States currently extend from the western portions of Nebraska and the Dakotas westward to the Cascade Mountains and from the northern counties of Arizona and New Mexico northward to the Canadian border. The data will be useful for identifying regions at increased risk of acquiring anaplasmosis in the United States. Based upon the database collection records, we also present a summary of recorded hosts for D. andersoni and comments on its seasonal occurrence.

New host and locality records for the Ixodes auritulus (Acari: Ixodidae) species group, with a review of host relationships and distribution in the Neotropical Zoogeographic Region.

New Neotropical records are presented for ticks belonging to the Ixodes auritulus Neumann, 1904, species group, together with a review of hosts and localities from which members of this complex have previously been collected. The range of the I. auritulus species group is now understood to include Colombia, and 15 bird species are listed as new hosts. From Guatemala to southern Argentina and Chile, specimens of the I. auritulus group have been found on birds belonging to the orders Ciconiiformes, Columbiformes, Falconiformes, Galliformes, Passeriformes, Piciformes, Procellariiformes and Tinamiformes. Passeriform birds are probably the principal hosts, sustaining tick populations throughout the Neotropics. Collection data have yielded four areas--southern South America (from 56 degrees S to 51 degrees S), southern Brazil (25 degrees S-22 degrees S), south-central Peru (14 degrees S-10 degrees S) and Central America (10 degrees N-15 degrees N)--where the I. auritulus group appears to commonly parasitize birds, but additional collections may show that the range of this complex is less discontinuous than currently perceived. Several morphological differences are described for ticks within and among these areas, but it is still unclear whether the I. auritulus group comprises more than one species.

Amblyomma latepunctatum, a valid tick species (Acari: Ixodidae) long misidentified with both amblyomma incisum and Amblyomma scalpturatum.

In 2000, we initiated an investigation on the tick fauna of Rondônia State, where we collected many specimens of Amblyomma scalpturatum Neumann, 1906 and Amblyomma incisum Neumann, 1906. In addition, we also collected a third group of ticks that were morphologically closely related to those 2 species, but sufficiently different to be considered a distinct species; members of this group were subsequently identified as Amblyomma latepunctatum Tonelli-Rondelli, 1939, through comparison with the type specimens of this taxon. Herein, we redescribe both sexes of A. scalpturatum and A. incisum, the female of A. latepunctatum, and provide the first description of the male of this latter species. Molecular analysis of the second internal transcribed spacer (ITS2) from rDNA of specimens of the 3 species supports morphological results. Examination of both A. scalpturatum and A. incisum deposited in different tick collections revealed that A. latepunctatum appeared relatively frequently in the vials believed to contain specimens of A. incisum or A. scalpturatum. Before this study, A. latepunctatum was considered a synonym of A. scalpturatum. Herein, we provide morphological and molecular evidence to validate the species A. latepunctatum. The South American tapir (Tapirus terrestris) seems to be the primary host for the adult stage of A. latepunctatum, A. scalpturatum, and A. incisum.

Hard tick calreticulin (CRT) gene coding regions have only one intron with conserved positions and variable sizes.

Calreticulin (CRT) is a unique eukaryotic gene. The CRT gene product, calreticulin, was first identified as a calcium binding protein in 1974, but further investigations have indicated that CRT protein performs many functions in cells, including involvement in evading the host's immune system by parasites. Many studies of CRT have been published since the molecule was first discovered; however, the CRT gene exon-intron structure is only known for a limited number of ectoparasite species. In this study, we compared tick CRT genomic sequences to the corresponding cDNA from 28 species and found that 2 exons and 1 intron are present in the tick CRT gene. The intron position is conserved in 28 hard ticks, but intron size and nucleotide sequences vary. Three tick introns possess duplicated fragments and are twice as long as other introns. All tick CRT introns obey the GT-AG rule in the splice-site junctions and are phase 1 introns. By comparing tick CRT introns to those of fruit fly, mouse, and human, we conclude that tick CRT introns belong to the intron-late type. The number and size of CRT introns have increased through the evolution of eukaryotes.

Redescription of larva, nymph and adults of Ixodes (I .) loricatus Neumann, 1899 (Acari: Ixodidae) based on light and scanning electron microscopy.

Ticks of the genus Ixodes are poorly known in the Neotropical zoogeographical region, from where only 45 species have been recorded. In Brazil, the genus is currently represented by eight species, four of which are known only from this country. This paper presents a redescription of all active stages in the life-cycle of I. loricatus , based on optical and scanning electron microscopy. In addition, the relationship of I. loricatus to other Neotropical Ixodes is presented and discussed.

Description of the nymph and larva and redescription of the female of Ixodes neuquenensis Ringuelet, 1947 (Acari: Ixodidae), a parasite of the endangered Neotropical marsupial Dromiciops gliroides Thomas (Microbiotheria: Microbiotheriidae).

The female of Ixodes neuquenensis Ringuelet, 1947 (Acari: Ixodidae) is redescribed and the nymph and larva are described from specimens collected from the endangered marsupial Dromiciops gliroides Thomas (Microbiotheria: Microbiotheriidae) in Argentina. At first sight the female of I. neuquenensis resembles a member of the subgenus Ixodes Latreille, 1795. However, the female of I. neuquenensis is peculiar in having the combination of two spurs on coxae II-IV and a pair of chitinous plaques internal to coxa I. Both the nymph and larva have an anterior and posterior process on palpal article I, characteristics of the subgenus Ixodiopsis Filippova, 1957 and some representatives of the subgenus Pholeoixodes Schulze, 1942. Analysis of 16S mitochondrial rDNA sequences showed no strong relationship with any known Ixodes subgenus.

Cloning and sequencing of putative calreticulin complementary DNAs from four hard tick species.

Calreticulin (CRT) is a calcium-binding protein and has many functions in eukaryotic cells. CRT is possibly involved in parasite host immune system evasion. To better understand the molecular basis of CRT in ticks, we cloned and sequenced 4 full-length complementary DNAs (cDNAs) from the hard tick species, Dermacentor variabilis, Haemaphysalis longicornis, Ixodes scapularis, and Rhipicephalus sanguineus, using the technique of rapid amplification of cDNA ends. The deduced amino acid sequences share high identities (between 77 and 98%) with 3 known tick CRT sequences. The major characteristics of known CRTs are observed in all 4 of our deduced tick CRTs. These include 3 major domains, a signal peptide sequence at the beginning of the coding region, 2 triplets of conserved regions, cysteine sites providing disulfide bridges for N-terminal folding, and a nuclear localization signal. Remarkably, the replacement of the endoplasmic reticulum retention signal KDEL by HEEL, which is believed to be associated with secretion of CRT into the host during feeding and was previously recorded only in 2 ticks and a hookworm, is also present in all 4 of our tick putative CRTs. In addition, the CRT gene is potentially useful for tick phylogenetic reconstruction.

Tick-borne relapsing fever caused by Borrelia hermsii, Montana.

Five persons contracted tick-borne relapsing fever after staying in a cabin in western Montana. Borrelia hermsii was isolated from the blood of two patients, and Ornithodoros hermsi ticks were collected from the cabin, the first demonstration of this bacterium and tick in Montana. Relapsing fever should be considered when patients who reside or have vacationed in western Montana exhibit a recurring febrile illness.

Molecular phylogenetic analyses indicate that the Ixodes ricinus complex is a paraphyletic group.

The Ixodes ricinus species complex is a group of ticks distributed in almost all geographic regions of the world. Lyme borreliosis spirochetes are primarily transmitted by tick species within this complex. It has been hypothesized that the Lyme vector ticks around the world are closely related and represent a monophyletic group. This implies that vector competence in ixodid ticks for Lyme agents might have evolved only once. To test this hypothesis, we used a molecular phylogenetic approach. Two fragments of mitochondrial 16S ribosomal deoxyribonucleic acid were sequenced from 11 species in the I. ricinus complex and from 16 other species of Ixodes. Phylogenetic analysis using Bayesian methodology indicated that the I. ricinus complex is not a monophyletic group unless 3 additional Ixodes species are included in it. The known major vectors of Lyme disease agents in different areas of the world are not sister taxa. This suggests that acquisition of the ability to transmit borreliosis agents in species of Ixodes may have multiple origins.

Ixodes (Multidentatus) paranaensis n. sp. (Acari: Ixodidae) a parasite of Streptoprocne biscutata (Sclater 1865) (Apodiformes: Apodidae) birds in Brazil.

During an ecological study, carried out between 1994 and 1996 with Streptoprocne biscutata (Sclater) (Apodiformes: Apodidae) birds, that inhabit caves in the Quatro Barras County, State of Paran , Southern Brazil, a new tick species of the subgenus Multidentatus was observed. The female, male, nymph, and larva of Ixodes (Multidentatus) paranaensis n. sp., are described. Of the 12 known species of the subgenus Multidentatus, only I. (M.) auritulus Neumann, 1904 and I. (M.) murreleti Cooley and Kohls, 1945 occur in the Neartic region and only I. (M.) auritulus occurs in the Neotropical region. As such, I. (M.) paranaensis n. sp. increases the number of species and the distribution area of the subgenus Multidentatus in the Americas.

New records and laboratory-rearing data for Ixodes schulzei (Acari: Ixodidae) in Brazil.

Ixodes schulzei Aragão and Fonseca was described from Brazil in 1951 based on female ticks collected on wild rats from the states of Rio de Janeiro and Santa Catarina. Since that time, there have been no additional reports of I. schulzei in the literature. We report two new records of I. schulzei: a female collected on the water rat Nectomys squamipes (Brants) from Minas Gerais State, and another female from this same host species from São Paulo State. This last specimen was engorged and oviposited fertile eggs in the laboratory. Larvae hatched from these eggs were used for subsequent infestations under laboratory conditions, as were nymphs obtained from the engorged larvae. Naive laboratory rats (Rattus norvegicus Berkenhout) and wild mice (Calomys callosus Rengger) were used to feed ticks. C. callosus was a more suitable host than R. norvegicus, as significantly more ticks (P < 0.05) were recovered and successfully molted after feeding on the former host species. A significantly (P < 0.05) greater proportion of larvae detached from C. callosus during daylight (71.3%) when compared with those that detached from R. norvegicus in the same period (54.8%). A total of nine engorged nymphs (one from R. norvegicus, and eight from C. callosus) were recovered in the infestations. All of them successfully molted to adults, which were all females. The male of I. schulzei remains unknown.

Ixodes (Multidentatus) paranaensis n. sp. (Acari: Ixodidae) a parasite of Streptoprocne biscutata (Sclater 1865) (Apodiformes: Apodidae) birds in Brazil

During an ecological study, carried out between 1994 and 1996 with Streptoprocne biscutata (Sclater) (Apodiformes: Apodidae) birds, that inhabit caves in the Quatro Barras County, State of Paraná, Southern Brazil, a new tick species of the subgenus Multidentatus was observed. The female, male, nymph, and larva of Ixodes (Multidentatus) paranaensis n. sp., are described. Of the 12 known species of the subgenus Multidentatus, only I. (M.) auritulus Neumann, 1904 and I. (M.) murreleti Cooley and Kohls, 1945 occur in the Neartic region and only I. (M.) auritulus occurs in the Neotropical region. As such, I. (M.) paranaensis n. sp. increases the number of species and the distribution area of the subgenus Multidentatus in the Americas

Cloning and sequencing of putative acetylcholinesterase cDNAs from the American dog tick, Dermacentor variabilis, and the brown dog tick, Rhipicephalus sanguineus (Acari: Ixodidae).

Two putative cDNAs of acetylcholinesterase (AChE), one from Dermacentor variabilis, and the other from Rhipicephalus sanguineus, were amplified and sequenced. The deduced amino acid sequences have high amino acid identities (between 70 and 94%) to known tick AChE sequences deposited in GenBank. Furthermore, these two AChEs also possess common features in their primary AChE structure such as catalytic active sites. A 2,220-bp contiguous sequence, containing a 1,791-bp open reading frame encoding an AChE precursor with 596 amino acid residues, was obtained from D. variabilis. The deduced proteins of R. sanguineus are different in size by 6 amino acids because of alternative splicing at the 5' end. A gene tree deduced from phylogenetic analysis indicates that there are at least three lineages of AChE in arthropods.

First evidence of the ocurrence of Amblyomma calcaratum Neumann, 1899 in peru / Primera evidencia de la ocurrencia de Amblyomma calcaratum Neumann, 1989 en Perú

Se reporta la presencia del ácaro Amblyomma calcaratum colectado en un ejemplar de un mirmecofagido Tamandua tetradactyla, capturado en julio del 2000 en la localidad de Bagua Grande, Amazonas, Perú. Se mencionan las relaciones filogenéticas de esta especie con A. nodosum y de su importancia médica.

Amblyomma geochelone, a new species of tick (Acari: Ixodidae) from the Madagascan ploughshare tortoise.

The male and female of Amblyomma geochelone n. sp. are described and illustrated by both scanning electron micrographs and line drawings. Specimens of this new tick species were recovered from the endangered ploughshare tortoise, Geochelone yniphora (Vaillant), in northwestern Madagascar. This relatively large tick is morphologically most similar to Amblyomma nuttalli Dönitz, which occurs in mainland sub-Saharan Africa where it mainly parasitizes other species of tortoises. However, several characters distinguish the new species from A. nuttalli including the scutal ornamentation in both sexes and the characteristic patterns of shallow grooves on the alloscutum of the female of A. geochelone. Because the adult stages of A. geochelone are almost certainly host specific ectoparasites of the ploughsh are tortoise, this new tick species is also probably endangered.

The Argasidae, Ixodidae and Nuttalliellidae (Acari: Ixodida): a world list of valid tick names.

The world's argasid tick fauna comprises 183 species in four genera, namely Argas, Carios, Ornithodoros and Otobius in the family Argasidae. The ixodid tick fauna consists of 241 species in the genus Ixodes and 442 species in the genera Amblyomma, Anomalohimalaya, Bothriocroton, Cosmiomma, Dermacentor, Haemaphysalis, Hyalomma, Margaropus, Nosomma, Rhipicentor and Rhipicephalus in the family Ixodidae, with the genus Boophilus becoming a subgenus of the genus Rhipicephalus. The family Nuttalliellidae is represented by the monospecific genus Nuttalliella. The species names of these ticks, based on seven previous complete or partial listings, as well as those of recently described new species, are presented in tabular format.

The use of the nuclear protein-encoding gene, RNA polymerase II, for tick molecular systematics.

Phylogenetic studies of ticks have been increasing in recent years, particularly in the use of molecular data. However, all of the studies to date are either limited to the mitochondrial genome or to a few nuclear ribosomal genes. There is a need to explore the use of nuclear protein-encoding genes because these genes direct most aspects of the phenotypic traits in the development of an organism. We report here the test of a nuclear protein-encoding gene, RNA polymerase II, for the phylogenetic study of ticks. Thirty-eight ticks representing 26 species of hard and soft ticks were chosen for the study. The pairwise divergences among sampled species are ranged from 0.3 to 15.2% and most of the substitutions are transitions. In addition, the nucleotide composition is not obviously biased in POL II gene. The trees inferred from the POL II sequences using maximum parsimony (MP), neighbor joining (NJ), and maximum likelihood (ML) by PAUP* and MrBayes are largely concordant with the existing phylogenies. Our study demonstrated that POL II gene sequences contain strong phylogenetic signals in ticks at the generic and higher levels. POL II has proven to be a useful gene for resolving tick phylogeny.

Ixodes (Haemixodes) longiscutatum Boero (new status) and I. (H.) uruguayensis Kohls & Clifford, a new synonym of I. (H.) longiscutatum (Acari: Ixodidae)

Females of Ixodes (Haemixodes) uruguayensis Kohls & Clifford, 1967, a species whose adults were unknown until the present, were obtained in the laboratory from engorged nymphs collected on rodents (Scapteromys tumidus and Oxymycterus nasutus) in the counties of Maldonado and San José, Uruguay. Morphological characters of these females were identical to those given in the description of the female of Ixodes longiscutatum Boero, 1944. I. uruguayensis is, thus, relegated to a junior subjective synonym of I. longiscutatum. However, because of the unique morphological characters of the immature stages, the validity of the subgenus Haemixodes Kohls & Clifford, 1967 is not questioned. Therefore, the new status of Ixodes (Haemixodes) uruguayensis Kohls & Clifford, 1967 is Ixodes (Haemixodes) longiscutatum Boero, 1944