Ectoparasites (sucking lice, fleas and ticks) of small mammals in southeastern Kenya.

During 1998-2000, at least 14 species (n = 309) of small mammals were live-trapped and examined for ectoparasites in moist forests of the Taita and Shimba Hills and drier savannah habitats of Nguruman, southeastern Kenya. Ectoparasites were recorded from 11 species of mammals. Five species of sucking lice [Hoplopleura inexpectans Johnson, H. intermedia Kellogg & Ferris, Polyplax reclinata (Nitzsch), P. waterstoni Bedford and Schizophthirus graphiuri Ferris], six species of fleas (Ctenophthalmus leptodactylous Hubbard, Dinopsyllus grypurus Jordan & Rothschild, D. lypusus Jordan & Rothschild, Hypsophthalmus campestris Jordan & Rothschild, Listropsylla basilewskyi Smit and Xiphiopsylla lippa Jordan) and at least six species of ticks (Amblyomma sp., Haemaphysalis sp., Ixodes sp., I. alluaudi Neumann, I. cumulatimpunctatus Schulze, I. muniensis Arthur & Burrow and Rhipicephalus sp.) were recorded from these hosts. Four of the five species of sucking lice were host specific whereas P. reclinata was recorded from two different species of white-toothed shrews, Crocidura spp. Although fleas and ticks were less host specific, C. leptodactylous, D. grypurus and I. cumulatimpunctatus were only recorded from the murid rodent Praomys delectorum (Thomas), Amblyomma sp. was only recorded from the nesomyid rodent Beamys hindei Thomas, Rhipicephalus sp. was only recorded from the murid Lemniscomys striatus (L.) and I. muniensis was only recorded from the dormouse Graphiurus microtis (Noack). More species of ectoparasites and significantly greater infestation prevalences were recorded from small mammals in moist habitats compared with those from the savannah habitat. At least one of the fleas recorded, D. lypusus, is a known vector of Yersinia pestis Lehmann & Neumann, the causative agent of plague, which is present in the region.

Ticks associated with wild animals in the Nhecolândia Pantanal, Brazil.

A study of ticks associated with wild animals was carried out from September 1996 to April 1998 at the Fazenda Alegria (21,000 ha), in the Nhecolândia Pantanal, State of Mato Grosso do Sul, Brazil, a sunken plain bordering the upper Paraguay river, located 19 x 08'S; 56 x 46'W. A total of 81 wild animals (13 species, 6 orders) were captured with the aid of nets, and ticks were found on 63 (78%). Tick species identified included Boophilus microplus (Canestrini), Amblyomma cajennense (F.), A. parvum (Aragão), A pseudoconcolor (Aragão), A. scalpturatum (Neumann), A. nodosum (Neumann), A. ovale (Koch), and A. tigrinum (Koch). Dragging from grasslands (campos) yielded negative results compared to the high concentration of ticks, mainly nymphs, that were collected from leaves in the forests (capão). Predominance of immature instars (Amblyomma genera) was observed in the end of winter (August-September). Ticks were associated mainly with coatis, deer (Mazama gouazoubira) and anteater, and these animals may play a role in the epidemiology of tick-transmitted pathogens in the Pantanal if one considers their co-existence with local domestic animals.

Isolation of a spotted fever group rickettsia from the Pacific Coast tick, Ixodes pacificus, in Oregon.

A rickettsia of the spotted fever group was isolated on three occasions from Ixodes pacificus in western Oregon. These isolations, and additional evidence furnished by complement fixation tests on guinea pigs inoculated with other Oregon ticks of this species, indicate that the association of this rickettsia with the Pacific Coast tick may be widespread. This is the first isolation of a spotted fever group rickettsia from I. pacificus. Because the Oregon isolates are mildly virulent for guinea pigs they resemble the Western U and Rickettsia montana strains of rickettsiae. However, preliminary evidence from cross-immunofluorescence tests of mouse antisera suggests the Tillamook and Grants Pass strains are antigenically different from all known spotted fever group agents.

Haemaphysalis juxtakochi Cooley (Acari: ixodidae), a neotropical tick species, found in Ohio.

Haemaphysalis juxtakochi Cooley, 1946, an ectoparasite of deer and other large mammals from Mexico southward through Central and South America, was recovered from the ear of a white-tailed deer, Odocoileus virginanus Zimmermann, in Ohio. This represents the first record of H. juxtakochi from the United States.

Illustrated key to nymphs of the tick genus Amblyomma (Acari: Ixodidae) found in the United States.

A dichotomous identification key, with important characters illustrated by scanning electron micrographs, is provided for nymphs of the 9 species of the genus Amblyomma occurring in the United States. Species included are A. americanum (L.), A. cajennense (F.), A. dissimile Koch, A. imitator Kohls, A. inornatum (Banks), A. longirostre (Koch), A maculatum Koch, A. rotundatum Koch, and A. tuberculatum Marx. Notes on the geographical distributions, medical and veterinary importance, and nymphal stage hosts are included for each species.

Pictorial key to the adults of hard ticks, family Ixodidae (Ixodida: Ixodoidea), east of the Mississippi River.

Six genera and 27 species of hard ticks (Ixodidae) currently are recognized in the United States east of the Mississippi River as follows: Amblyomma (4 species), Boophilus (1), Dermacentor (3), Haemaphysalis (2), Ixodes (16), and Rhipicephalus (1). We present a diagrammatic couplet key to the adults of the six genera and 27 species of Ixodidae found in the eastern portion of the United States.

Invasion: exotic ticks (Acari: Argasidae, Ixodidae) imported into the United States. A review and new records.

A review of the literature and unpublished records from the U.S. National Tick Collection on the importation of ticks from foreign lands reveals that at least 99 exotic tick species assignable to 11 genera have been either detected and destroyed at ports of entry or inadvertently imported into the United States in the past half century. This number includes four argasid and 95 ixodid species, some of which are important vectors of agents that cause disease to both man and animals. If one includes Aponomma sp. and Hyalomma sp. and the subspecies of Rhipicephalus, the total exceeds 100 taxa. It is notable that the number of imported tick species recorded herein exceeds the total number of tick species native to the United States. It appears that the soft tick genera Argas, Antricola and Nothoaspis have not been imported, although at some point in time Argas persicus (Oken) was introduced because it is resident although not often collected. The hard tick genera Anomalohimalaya, Cosmiomma, Margaropus, Nosomma and Rhipicentor, and the nuttalliellid genus Nuttalliella have also not been imported.

Ixodes (Ixodes) jellisoni and I. (I.) neotomae (Acari:Ixodidae): descriptions of the immature stages from California.

Nymphal and larval stages of Ixodes (Ixodes) jellisoni Cooley & Kohls and I. (I.) neotomae Cooley are described for the first time. These 2 tick species occur only in the western United States, predominantly in California. The primary host for I. jellisoni is the California kangaroo rat, Dipodomys californicus (Merriam); that for I. neotomae is the dusky-footed woodrat, Neotoma fuscipes Baird. The etiologic agent of Lyme disease Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt & Brenner has recently been isolated from both tick species, and I. neotomae was proven a competent enzootic vector of the Lyme disease spirochete.

Description of the immature stages of Ixodes (Pholeoixodes) baergi (Acari: Ixodidae), a parasite of cliff swallows in the United States.

The larva and nymph of Ixodes (Pholeoixodes) baergi Cooley & Kohls are described for the first time. This tick has been collected only in the United States on cliff swallows, Hirundo pyrrhonota, in their nests, or in adjacent habitats. To date, it has been reported from Arkansas, Colorado, Illinois, Oklahoma, and Texas. Brief notes on the synchronization of the life cycle of I. baergi with that of its host are included.

Ornithodoros (Alectorobius) capensis Neumann (Acari: Ixodoidea: Argasidae), a parasite of seabirds, established along the southeastern seacoast of the United States.

Ornithodoros (Alectorobius) capensis Neumann, an ectoparasite of seabirds found circumglobally in the tropics and subtropics, has become established along the southeastern seacoast of the United States. The tick has been found feeding primarily on brown pelicans, Pelecanus occidentalis, but also has been found on the laughing gull, Larus atricilla, and the American oystercatcher, Haematopus palliatus. We report here the presence of O. (A.) capensis from New Hanover and Brunswick counties (near the mouth of the Cape Fear River) in North Carolina, to the Charleston Harbor area of South Carolina and thence south to Cumberland Island (a barrier island) in Camden County, Georgia, just north of the Florida state line.

Aponomma (Bothriocroton) glebopalma, n. subgen., n. sp., and Amblyomma glauerti n. sp. (Acari: Ixodida: Ixodidae), parasites of monitor lizards (Varanidae) in Australia.

Aponomma (Bothriocroton) glebopalma, n. subgen., n. sp., and Amblyomma glauerti, n. sp. (Acari: Ixodidae), are described from the monitor lizards Varanus glebopalma Mitchell and Varanus glauerti Mertens in Western Australia and the Northern Territory, Australia. The new subgenus is erected to accomodate A. (Bothriocroton) glebopalma, a new species with a deeply pitted and pilose scutum in both the adult and immature stages, unlike all other described species of Aponomma. This new species is found in an area where Aponomma fimbriatum Koch, a parasite of varanid lizards and various species of snakes, was the only known member of the genus found in both Western Australia and the Northern Territory. Amblyomma glauerti n. sp., an ornate Australian reptile tick found on the same two hosts in Western Australia and the Northern Territory, is also described. These two new species were recovered from formalin-preserved lizard specimens; therefore, nothing is known of their life cycles, except that all stages parasitize varanid lizards.

Ixodes (Ixodes) scapularis (Acari:Ixodidae): redescription of all active stages, distribution, hosts, geographical variation, and medical and veterinary importance.

The blacklegged tick, Ixodes (Ixodes) scapularis Say, 1821, is redescribed, based on laboratory reared specimens originating in Bulloch County, Georgia. Information on distribution, host associations, morphological variation, and medical/veterinary importance is also presented. A great deal of recent work has focused on this species because it is the principal vector of the agent of Lyme disease (Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwaldt & Brenner) in eastern North America. Its distribution appears to be expanding, and includes the state of Florida in the southeastern United States north to the provinces of Nova Scotia and Prince Edward Island, Canada, west to North and South Dakota, United States, and south to the state of Coahuila, Mexico. Although I. scapularis feeds on at least 125 species of North American vertebrates (54 mammalian, 57 avian, and 14 lizard species), analysis of the U.S. National Tick Collection holdings show that white-tailed deer, Odocoileus virginianus (Zimmermann), cattle, Bos taurus L., dogs, Canis lupus L., and other medium-to-large sized mammals are important hosts for adults as are native mice and other small mammals, certain ground-frequenting birds, skinks, and glass lizards for nymphs and larvae. This tick is a polytypic species exhibiting north-south and east-west morphological clines. Analysis of variance and Student-Newman-Keuls multiple comparisons revealed significant interpopulational variation that is expressed most significantly in the nymphal stage. Nymphs from northern (Minnesota, Massachusetts, Maryland) populations had relatively larger basis capituli with shorter cornua (except Maryland) than southern (North Carolina, Georgia) populations. Midwestern populations (Minnesota, Missouri) differed from eastern populations (Massachusetts, Maryland, North Carolina, Georgia) in idiosomal characters (broader scuta, larger coxae III, and IV). In addition to Lyme disease, this tick is also a primary vector of the agent of human and rodent babesiosis, Babesia microti Franca. Under laboratory conditions it has transmitted the agents of deer babesiosis, Babesia odocoilei Emerson & Wright, tularemia, Francisella tularensis McCoy & Chapin, and anaplasmosis, Anaplasma marginale Theiler. Moreover, I. scapularis can reach pest proportions on livestock, and females can cause tick paralysis in dogs.

Annotated list of ticks (Acari: Ixodidae, Argasidae) reported in Peru: distribution, hosts, and bibliography.

A literature review and compilation of the tick specimens found in Peru and now held in the National Tick Collection was carried out to develop a working list of the tick species likely to be found in Peru. Evidence of 44 species (29 Ixodidae, 15 Argasidae), was found; representatives of 40 species are held as reference specimens. This report adds 14 species to the previously published list.

First report of Ixodes (Ixodes) minor Neumann (Acari: Ixodidae) from South Carolina.

Previous reports from the literature have indicated the northernmost range of extension of Ixodes minor Neumann to be southern Georgia with the greatest number of collections having been made in the coastal regions of that state. An unpublished record in the U.S. National Tick Collection indicated that I. minor had been collected as far north as South Island, Georgetown County, S.C., as early as 1933. I. minor was collected on three separate occasions in Charleston County, S.C., between October 1990 and February 1991, thus verifying the northern extension of this tick's range and the probable existence of a stable population on the coast of South Carolina. The roof rat (Rattus rattus) is reported for the first time serving as a host for I. minor.

Population genetics of Ixodes scapularis (Acari: Ixodidae) based on mitochondrial 16S and 12S genes.

Blacklegged tick, Ixodes scapularis Say, is the principal vector of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner in the eastern half of the United States. Populations exhibit extreme variation in morphology, host usage, development time, and behavior. We examined sequence variation in the 16S and 12S mitochondrial ribosomal DNA genes to determine genetic relationships among I. scapularis collections from throughout its range. Single strand conformation polymorphism analysis of 300 bp of the 16S molecule was used to identify different haplotypes and estimate their relative frequencies among 198 ticks. Eleven different haplotypes were detected. Haplotype diversity was least in northeastern collections and greatest in the southeast. The 11 haplotypes were sequenced in 24 specimens. In total, 462 bp in the 16S gene and 420 bp in the 12S gene were sequenced to reveal 66 informative sites. Phylogenetic analysis, using I. ricinus L. and I. pacificus Cooley & Kohls as outgroups, revealed 2 clades within I. scapularis. One clade was limited to the South and the other was distributed throughout the range of I. scapularis. Specimens from the Southern United States were basal in the broadly distributed clade. Random amplified polymorphic DNA by polymerase chain reaction patterns examined between members of the 2 clades provided no evidence for reproductive isolation. These patterns suggest that I. scapularis arose in the South but that a large geographic split gave rise to 2 distinct lineages. These lineages now interbreed and are partially sympatric.

Ornithodoros (Alectorobius) puertoricensis (Acari: Argasidae): redescription by scanning electron microscopy.

The female, male, nymphal instars, and larva of Ornithodoros puertoricensis Fox are redescribed from specimens collected in Haiti. Data on host species and geographic distribution are also presented.

Ticks (Acari: Ixodidae) associated with wild animals in the Pantanal region of Brazil.

This paper describes the identification of ticks from wild animals of the Pantanal region in Brazil as part of a comprehensive study about established and emerging tick-host relationships and related pathological aspects. Eighty-one animals were captured (representing 13 species, six orders), and ticks were found on 63 (78%). Tick species identified included Boophilus microplus (Canestrini), Amblyomma cajennense (F.), Amblyomma parvum Aragão, Amblyomma pseudoconcolor Aragão, Amblyomma scalpturatum Neumann, Amblyomma nodosum Neumann, Amblyomma ovale Koch, and Amblyomma tigrinum Koch. Dragging from grasslands yielded negative results compared with the high concentration of ticks that were collected from leaves in the forests.

Taxonomic status of Ixodes neotomae and I. spinipalpis (Acari: Ixodidae) based on mitochondrial DNA evidence.

Ixodes spinipalpis Hadwen & Nuttall and I. neotomae Cooley are enzootic vectors of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner in western North America. The taxa overlap in host preference, habitat, and morphology. Mitochondrial DNA was compared between the taxa to test for reproductive isolation. A 300-bp region of the mitochondrial 16S ribosomal DNA gene was amplified in 28 specimens of I. neotomae and 149 specimens of I. spinipalpis. These products were screened for sequence variation using single-strand conformation polymorphism analysis, and 9 haplotypes were detected. Haplotype frequencies varied between taxa; however, Shannon diversity analysis indicated that most variation arose among collections within each taxon, and no unique haplotypes characterized either one. Phylogenetic analysis of 18 sequences, representing a replicate of each of the 9 haplotypes, was performed with Ixodes pacificus Cooley & Kohls and Ixodes jellisoni Cooley & Kohls as outgroups. Strong monophyletic support was found for a clade containing I. neotomae and I spinipalpis and within this clade no lineages comprised exclusively either taxon. These results argue against treatment of I. neotomae and I. spinipalpis as distinct species.

Amblyomma aureolatum (Pallas, 1772) and Amblyomma ovale Koch, 1844 (Acari: Ixodidae): hosts, distribution and 16S rDNA sequences.

DNA sequences of Amblyomma aureolatum (Pallas, 1772) and Amblyomma ovale Koch, 1844 were obtained to determine genetic differences between these tick species. Collections of these species are discussed in relation to distribution and hosts. Seven ticks collections (four from Brazil, one from Argentina, one from Uruguay and one from USA) house a total of 1272 A. aureolatum (224 males, 251 females, 223 nymphs and 574 larvae) and 1164 A. ovale (535 males, 556 females, 66 nymphs and 7 larvae). The length of the sequenced mitochondrial 16S rRNA gene fragment for A. aureolatum was 370bp and for A. ovale was 373bp. The DNA sequence analysis showed a 13.1% difference between the two species. Apart from one male A. ovale found on a toad, all adult ticks were found on mammals. The majority of adult specimens of both tick species were removed from Carnivora (96.1 and 84.3% of A. aureolatum and A. ovale, respectively), especially from dogs (53.1% of A. aureolatum, and 46.4% of A. ovale). Collections on wild Canidae were higher for A. aureolatum (23.3%) than for A. ovale (7.1%). On the other hand, collections of A. ovale adults on wild Felidae were higher (18.3%) than findings of A. aureolatum (9.2%). The contribution of other mammalian orders as hosts for adults of A. aureolatum and A. ovale was irrelevant, with the exception of Perissodactyla because Tapiridae contributed with 13.0% of the total number of A. ovale adults. Adults of both tick species have been found occasionally on domestic hosts (apart of the dog) and humans. Most immature stages of A. aureolatum were found on Passeriformes birds, while rodents and carnivores were the most common hosts for nymphs and larvae of A. ovale. A. aureolatum has been found restricted to the Neotropical region, covering the eastern area of South America from Uruguay to Surinam, including northeastern Argentina, eastern Paraguay, southeastern Brazil and French Guiana. A. ovale showed a distribution that covers the Neotropical region from central-northern Argentina throughout the Neotropics into the Nearctic region of Mexico with a few records from the USA, also with collection sites in Paraguay, Bolivia, most Brazilian states, Peru, Ecuador, French Guiana, Surinam, Guyana, Trinidad & Tobago, Venezuela, Colombia, Panama, Costa Rica, Nicaragua, Belize, Guatemala and several states of Mexico.