Morphological and molecular identification of medically important questing Dermacentor species collected from some recreational areas of Peninsular Malaysia.

Questing is a situation when a tick is seeking to get closer or ambush its potential host. However, information on questing tick species in Malaysia is still lacking, thus the association with tick-borne diseases (TBD) is not completely understood. The aim of this study was to investigate the tick species from five most frequently visited recreational areas in Pahang and Terengganu states, which were recorded to have high potential of TBD cases. By implementing handpick method, a total of 18 males and 15 females belonging to five Dermacentor Koch, 1844 species, were collected, namely D. compactus Neumann 1901, D. tricuspis (Schulze, 1933), D. auratus Supino 1897, D. steini (Schulze, 1933), and D. falsosteini Apanaskevich, Apanaskevich & Nooma respectively. The specimens were collected and identified based on morphological characters prior to obtaining the molecular data of COI and 16S rDNA. The D. compactus was the most abundant species collected in this study, while D. falsosteini was the least. All species were distinctly separated on the Neighbor Joining and Maximum Parsimony tree topologies and supported with high bootstrap values. Furthermore, a low intraspecific variation (0.00 - 0.01) was observed amongst the individuals of the same species in both genes. Meanwhile, each Dermacentor species was genetically different, with interspecific values ranging from 0.13-0.19 and 0.11-0.20 for COI and 16S rDNA. These findings had successfully recorded the tick species that were potentially associated with TBD, and which might be circulated among humans and animals. This study also has some implications on the diversity and geographical extension of Dermacentor ticks, thus should warrant further investigation as a potential vector of tick-borne diseases and public health importance.

Integrative Taxonomy of Dermacentor variabilis (Ixodida: Ixodidae) with Description of a New Species, Dermacentor similis n. sp.

Dermacentor variabilis is the most widely distributed three-host tick in North America, and transmits a variety of pathogens. Within the United States, this species has a discontinuous distribution, widespread east of the Rocky Mountains and with a few populations west of the Rockies. Phylogenetic evidence based on individual markers or relatively small data sets has suggested that populations at both sides of this geographic barrier may correspond to two different species. In this study, we further explore this hypothesis using an integrative taxonomy framework. Both molecular (mitochondrial and nuclear markers) and morphological analyses of specimens collected from central-eastern and western states were performed to explore species delimitation in this taxon. Results from these analyses were consistent, and provide strong evidence that D. variabilis actually corresponds to two species. Herein, the western populations are described as a new species, Dermacentor similis n. sp. The usefulness of integrative taxonomy in the context of species delimitation is also discussed.

Reinstatement of Dermacentor tricuspis (Schulze, 1933) n. comb., n. stat. (Acari: Ixodidae) as a valid species, synonymization of D. atrosignatus Neumann, 1906 and description of a new species from Indonesia, Malaysia and Thailand.

Re-examination of the holotype of Dermacentor atrosignatus Neumann, 1906 (Acari: Ixodidae) stored in the Natural History Museum (London, UK) revealed that this taxon is identical with D. auratus Supino, 1897 and should be treated as a junior synonym of the latter species. A correct name for the distinct species previously identified as D. atrosignatus Neumann, 1906 sensu Wassef & Hoogstraal, 1984 should be D. tricuspis (Schulze, 1933) n. comb., n. stat. Adults of D. tricuspis are redescribed here. Re-examination of extensive holdings of Oriental Dermacentor Koch, 1844 ticks stored in the United States National Tick Collection revealed that a morphologically distinct new species of this genus, namely D. falsosteini D. Apanaskevich, M. Apanaskevich & Nooma n. sp. should be recognized. Adults of D. tricuspis and D. falsosteini n. sp. can be distinguished from other species of Oriental Dermacentor and each other by the colour pattern of the conscutum and scutum, the pattern of punctations on the pseudoscutum and scutum, the shape of female genital structures and spurs on coxa I. Dermacentor tricuspis is recorded from Indonesia, Malaysia, the Philippines and Thailand where the adults were mostly collected from various species of wild pigs (Artiodactyla: Suidae) and vegetation; few adults were available from other mammals (Artiodactyla: Bovidae; Carnivora: Canidae, Felidae, Ursidae; Pholidota: Manidae), as well as humans and reptiles (Squamata: Elapidae, Varanidae). One male was reared from a nymph collected on a rodent (Rodentia: Muridae). Dermacentor falsosteini n. sp. is found in Indonesia, Malaysia and Thailand where the adults were collected from bearded pig, Sus barbatus Müller, wild boar, S. scrofa Linnaeus, unidentified wild pig, Sus sp. (Artiodactyla: Suidae), Malayan tapir, Tapirus indicus Desmarest (Perissodactyla: Tapiridae), human and vegetation.

Description of a new species of Dermacentor Koch, 1844 (Acari: Ixodidae) from the mountains of Laos and Thailand.

Dermacentor pasteuri n. sp. (Acari: Ixodidae) is described based on adults ex wild boar and vegetation from Laos and Thailand. Adults of D. pasteuri n. sp. are similar to those of D. compactus Neumann, 1901, but can be distinguished by the shape of conscutum in the male, development of dorsal cornua in the female, size and shape of spurs on coxae and coloration of leg segments in both sexes.

First Report of the Ticks Haemaphysalis punctata Canestrini et Fanzago, 1878, Haemaphysalis parva (Neumann, 1897) and Dermacentor marginatus (Sulzer, 1776) (Acari, Amblyommidae) from Humans in Lebanon.

PURPOSE: Knowledge on ticks infesting humans is scarce for the middle East. In this work, tick specimens (Acari: Amblyommidae) infesting humans in Lebanon were identified. METHODS: Ticks that were found on humans were received in the Lebanese University, Faculty of Sciences. The specimens were preserved in alcohol for their further morphological identification. RESULTS: Three tick species were identified: a red sheep tick Haemaphysalis punctata Canestrini et Fanzago, 1878, a Mediterranean ear tick H. parva (Neumann, 1897), and an ornate sheep tick Dermacentor marginatus (Sulzer, 1776); all isolated from human hosts. CONCLUSION: This is the first report of Haemaphysalis punctata, H. parva and Dermacentor marginatus infesting humans from Central and North Lebanon.

Description of a new species of Dermacentor Koch, 1844 (Acari: Ixodidae) from Laos and Thailand.

Dermacentor laothaiensis n. sp. (Acari: Ixodidae) is described based on adults ex wild boar and vegetation from Laos and Thailand. Adults of D. laothaiensis n. sp. are similar to those of D. bellulus (Schulze, 1935) and D. steini (Schulze, 1933) but can be distinguished by the conscutum shape, colour pattern of the conscutum and scutum, the density of punctations on the pseudoscutum and scutum and the shape of female genital structures.

Tissue localization of Coxiella-like endosymbionts in three European tick species through fluorescence in situ hybridization.

Ticks are commonly infected by Coxiella-like endosymbionts (Coxiella-LE) which are thought to supply missing B vitamin nutrients required for blood digestion.While this nutritional symbiosis is essential for the survival and reproduction of infected tick species, our knowledge of where Coxiella-LE is localized in tick tissues is partial at best since previous studies have focused on a limited number of Asian or American tick species. To fill this gap, we investigated the tissue localization of Coxiella-LE in three European tick species, Ornithodoros maritimus, Dermacentor marginatus and Ixodes hexagonus, using a diagnostic fluorescence in situ hybridization (FISH) assay, combined with PCR-based detection. Specific fluorescent foci were observed in several tick tissues. We visualized a pronounced tissue tropism of Coxiella-LE for tick ovaries and Malpighian tubules, a pattern suggestive of a high degree of lifestyle specialization toward mutualism: infection of the ovaries is indicative of transovarial transmission, whereas infection of the Malpighian tubules suggests a nutritional function. We postulate that Malpighian tubules are key organs for the nutritional symbiosis, notably the synthesis of B vitamins by Coxiella-LE, whereas the infection of the ovaries ensures vertical transmission of the symbionts to future generations. We also detected occasional infections in other organs, such as salivary glands and the midgut. Finally, we discuss the potential significance of the different tissue tropism for tick biology.

Morphometric Analysis of Adult Dermacentor parumapertus Neumann (Acari: Ixodidae) From Various Locations Within its Geographical Range.

Dermacentor parumapertus Neumann (Acari: Ixodidae), a tick primarily associated with rabbits which occurs over much of the western United States, has a fairly large north-to-south distribution, being found from central Idaho southward into northern Mexico. This mostly obscure tick species has recently been the focus of attention due to the discovery of a unique strain of Rickettsia parkeri associated with it which appears closely related to a Rickettsia sp. found in the Atlantic rainforest of Brazil. Historically, a morphological variety of this species was reported in the literature based on significant variation in ornamentation of the tick throughout its range. This study examines several key morphological characters to determine if there are indeed more than one distinct population of this species throughout its range.

First description of the nymph and larva of Dermacentor compactus Neumann, 1901 (Acari: Ixodidae), parasites of squirrels (Rodentia: Sciuridae) in southeast Asia.

Recent reexamination of collection lots stored in the United States National Tick Collection revealed adult specimens of Dermacentor compactus Neumann, 1901 (Acari: Ixodidae) reared from field-collected nymphs, which allowed us to associate field-collected unidentified nymphs and larvae with this species. Nymphs of D. compactus can be easily distinguished from those of other congeneric species by the shape of the scutum and spiracular plate, the hypostome dentition, and the size of the spurs on the coxae. Larvae of this species can be distinguished by the shape and sculpture of the scutum, the shape of basis capituli, the absence of auriculae, and the size of the spurs on coxae II and III. Both nymphs and larvae feed mostly on various species of squirrels (Rodentia: Sciuridae). Considerably fewer nymphs and larvae were found on murid rodents (Rodentia: Muridae), domestic dogs (Carnivora: Canidae), and a snake (Squamata: Colubridae).

Description of two new species of Dermacentor Koch, 1844 (Acari: Ixodidae) from Oriental Asia.

Dermacentor tamokensis n. sp. and Dermacentor pseudocompactus n. sp. (Acari: Ixodidae) are described based on adults ex wild boar and vegetation from China, India, Malaysia, and Vietnam and males ex wild boar from Nepal, respectively. Adults of D. tamokensis n. sp. are similar to those of D. taiwanensis Sugimoto, 1935 and D. atrosignatus Neumann, 1906 but can be distinguished by the colour pattern of the conscutum and scutum, the size and density of punctations on the pseudoscutum and scutum, the width of the cornua, and the shape of female genital structures. Males of D. pseudocompactus n. sp. are most similar to those of D. compactus Neumann, 1901 but can be distinguished by the colour pattern, sculpture and punctations of the conscutum, and the shape and length of the coxal spurs.

Description of a New Dermacentor (Acari: Ixodidae) Species from Thailand and Vietnam.

A new tick species belonging to the genus Dermacentor Koch, 1844, namely, Dermacentor filippovae n. sp., is described. All stages of this species are similar to those of D. auratus Supino, 1897, D. compactus Neumann, 1901, and D. limbooliati Apanaskevich and Apanaskevich, 2015 with which it was previously confused. Males of D. filippovae may be distinguished from those of D. auratus, D. compactus, and D. limbooliati by the following suite of characters: conscutum broadly oval with convex lateral sides, widest posteriorly; trapezium-like shape of pseudoscutum; central brown patch on conscutum indistinct; coxa I with internal spur narrowly triangular with tapering apex and external spur fairly long, narrowly triangular with tapering apex; numerous internal spurs on coxa IV; and trochanter I with moderate, broadly triangular spur with tapering apex. Females of D. filippovae may be distinguished from those of D. auratus, D. compactus, and D. limbooliati by the following suite of characters: central patch of scutum narrow, distinct line interrupted around midlength; more rounded shape of scutum; long and distinct alloscutal setae; moderately broad U-shaped genital aperture with preatrial fold bulging anteriorly and thereafter sharply sloping to flat surface posteriorly; coxa I with internal spur narrowly triangular with tapering apex and external spur fairly long, narrowly triangular with tapering apex; and trochanter I with moderate, broadly triangular spur with tapering apex. Dermacentor filippovae is known from Thailand and Vietnam where the adults were collected from wild boar, Sus scrofa L., and vegetation.

Description of New Dermacentor (Acari: Ixodidae) Species from Malaysia and Vietnam.

A new tick species belonging to the genus Dermacentor Koch, 1844, namely, Dermacentor limbooliati n. sp., is described. Adults of this species are similar to those of Dermacentor auratus Supino, 1897 and Dermacentor compactus Neumann, 1901, with which it was previously confused. Males of D. limbooliati may be distinguished from those of D. auratus and D. compactus by the following suite of characters: relatively broad conscutum with slightly straightened lateral sides, conscutum widest approximately at mid-length, oval shape of pseudoscutum, central brown patch in the center of pseudoscutum broad and diffused and not continuous with central patch in posteromedian area, conscutum posterior to pseudoscutum rugose, wide and blunt internal spur on coxa I, relatively long, narrow, and pointed external spur on coxa I, numerous internal spurs on coxa IV and trochanter I with moderate and broadly triangular spur with tapering apex. Females of D. limbooliati may be distinguished from those of D. auratus and D. compactus by the following suite of characters: rounded shape of scutum, central brown patch broad and diffused in the center of scutum, relatively long alloscutum setae, genital aperture moderately narrow V-shaped with preatrial fold bulging, wide and blunt internal spur on coxa I, relatively long, narrow, and pointed external spur on coxae I and trochanter I with moderate and broadly triangular spur with tapering apex. D. limbooliati is known from Malaysia and Vietnam where the adults were collected from vegetation, Sus scrofa resting beds, a human, and clothing. The immature stages remain unknown.

Reinstatement of Dermacentor bellulus (Acari: Ixodidae) as a Valid Species Previously Confused with D. taiwanensis and Comparison of All Parasitic Stages.

Re-examination of Dermacentor taiwanensis Sugimoto, 1935 specimens in the United States National Tick Collection revealed that two morphologically distinct Dermacentor species were identified under this name. One of them corresponds to Sugimoto's description of D. taiwanensis, while another species is identical to Schulze's Dermacentor bellulus (Schulze, 1935). The latter species has not been considered valid by recent workers. D. bellulus is reinstated here as a valid species and all its stages are redescribed. The adults of D. taiwanensis are also redescribed, and its immature stages are described for the first time. Males and females of D. bellulus can be distinguished from those of D. taiwanensis by the shape of the conscutum and scutum, color pattern, genital structures, size of the palpi and cornua, and the spurs of coxa I. Nymphs of D. bellulus can be distinguished from those of D. taiwanensis by the shape of the scutum, basis capituli, and the hypostomal dentition. Larvae of D. bellulus can be differentiated from those of D. taiwanensis by the shape of the basis capituli, and the degree of development of the auriculae and spur on palpal segment III ventrally. D. bellulus has been recorded from China, Japan, Nepal, Taiwan, and Vietnam; adults have been collected from wild boars, bears, panda, dog, and human; the immature stages are known from rodents, hares, ferret-badger, and bamboo-partridge. D. taiwanensis is found in China, Taiwan, and Vietnam; adults have been collected from wild boars; the immature stages are known from rodents, hares, mustelids, and domestic dog.

Redescription of Dermacentor everestianus Hirst (Acari: Ixodidae), a parasite of mammals in mountains of China and Nepal with synonymization of D. abaensis Teng and D. birulai Olenev.

Examination of extensive Dermacentor Koch, 1844 holdings stored in several major tick collections allowed us to re-evaluate the taxonomic content of Dermacentor everestianus Hirst, 1926 and redescribe all of its parasitic stages in detail for the first time. Examination of the type specimens of Dermacentor abaensis Teng, 1963 , a species treated as valid by most workers, and Dermacentor birulai Olenev, 1927 , a species some recent authors considered as valid, led us to the conclusion that they are junior synonyms of D. everestianus. The relation of D. everestianus with some other species in the genus is questionable and warrants further studies. From possibly sympatric Dermacentor species, the adults of D. everestianus can be distinguished by the following combination of characters: intensive ivory colored ornamentation of conscutum and scutum, absence of brown patches on lateral fields of conscutum in the male, long and narrow dorsal prolongation of spiracular plates, short cornua, short dorsal spur on trochanter I, and absence of large ventral spur on distal ends of genua and tibiae II-IV. Nymphs of D. everestianus can be distinguished by numerous setae on alloscutum (>48 pairs), large spiracular plates with their longitudinal diameter exceeding that of sclerotized ring around anal valves, moderate lateral projections of basis capituli with blunt apices situated slightly posterior to the midlength of basis capituli dorsally, relatively large auriculae, relatively short, narrowly rounded at apices spurs on coxae I with internal spur being shorter than external and moderate triangular spur on coxae IV; while larvae can surprisingly easily be distinguished from those of other species found in the region by greatly elongated posterior portion of scutum where eyes are situated just posterior to the midlength of scutum. So far, D. everestianus is found only in China and Nepal, where the adults were collected from domestic and wild ungulates while the immature stages were recorded from lagomorphs and rodents.

First description of the nymph and larva of Dermacentor raskemensis (Acari: Ixodidae), parasites of pikas and other small mammals in Central Asia.

Dermacentor raskemensis Pomerantzev, 1946 is one of the rare Asian species in this genus. The immature stages of this species have never been described. Reexamination of D. raskemensis holdings stored in the United States National Tick Collection revealed a collection lot containing reared nymphs and larvae of this species. This collection made it possible for us to find numerous nymphs and larvae of D. raskemensis among previously unidentified material collected in the field. Both immature stages of D. raskemensis are described here for the first time. Nymphs of D. raskemensis can be distinguished from those of other Dermacentor species in the region by small spiracular plate, relatively short and obtuse lateral projections of basis capituli dorsally, relatively short spurs on coxa I and the internal spur is characteristically very broadly rounded at its apex, and very small spur on coxa IV, whereas larvae of D. raskemensis can be distinguished from other Dermacentor by relatively short and obtuse lateral projections of basis capituli, approximately 6 denticles in the median files on hypostome, and relatively short, broad, and rounded spur on coxa I. The nymphs and larvae of D. raskemensis studied originate from Afghanistan, India, Iran, and Pakistan, where they were collected from pikas and other small mammals.

Reinstatement of Dermacentor kamshadalus Neumann (Acari: Ixodidae) as a valid species parasitizing mountain goats and sheep in the United States, Canada, and Russia.

Reexamination of Dermacentor albipictus (Packard, 1869) holdings stored in the United States National Tick Collection revealed several collections of a morphologically distinct Dermacentor species. Comparison of these specimens with other Dermacentor taxa showed that they are identical to an old taxon originally described as Dermacentor variegatus kamshadalus Neumann, 1908. For more than a century, this taxon was known only from the male holotype specimen collected in Russia, and the name was considered a junior synonym of D. albipictus. D. kamshadalus is reinstated here to a full species rank, and its male is redescribed and its female and nymph are described for the first time. Adults of D. kamshadalus can be distinguished from those of D. albipictus by a short spur on trochanters I, shorter spurs on coxae I, shorter dorsal cornua, more numerous perforations on spiracular plates, less numerous and shorter setae on idiosoma, especially around spiracular plates, and considerably paler coloration of the conscutum and scutum. The nymph of D. kamshadalus can be differentiated from that of D. albipictus by shorter spurs on coxae I and the numerous perforations on the spiracular plates. Adults and nymphs ofD. kamshadalus are recorded from the United States, Canada, and Russia, where they have been collected from mountain goats, Oreamnos americanus (de Blainville), bighorn sheep, Ovis canadensis Shaw, and sheep, Ovis sp. of which the species was not stated.

Description of a new Dermacentor (Acari: Ixodidae) species, a parasite of wild mammals in Central America.

A new tick species belonging to the genus Dermacentor Koch, 1844, Dermacentor panamensis n. sp., is described. All stages of this species are similar to those of Dermacentor halli McIntosh, 1931, with which it was confused for a long time. Males of D. panamensis can be distinguished from those of D. halli by the following suite of characters: narrower conscutum, broader basis capituli, shorter dorsal cornua, narrower palpi, palpal segment III tapering to its apex, legs poorly ornate: ivory colored patches present only on dorsal aspects of leg segments (mostly on legs III and IV), and internal spur of coxae I narrower and more tapering. Females of D. panamensis can be distinguished from those of D. halli by the following suite of characters: narrower and less ornate scutum, broader basis capituli, shorter dorsal cornua, larger porose areas, narrower palpi, palpal segment III tapering to its apex, legs poorly ornate: ivory colored patches present only on dorsal aspects of leg segments (mostly on legs III and IV), and internal spur of coxae I narrower and more tapering. Nymphs of D. panamensis can be distinguished from those of D. halli by clear posterolateral projections of scutum and by absence of coxal "pore" on coxae I-IV, while larvae of D. panamensis can be distinguished from those ofD. halli by shorter and less sharp lateral projections of basis capituli dorsally and slightly sharp anterior angle of basis capituli. D. panamensis is known from highlands of Costa Rica, Guatemala, Honduras, Nicaragua, and Panama where the adults were collected from porcupines and unidentified sloth and mouse while nymphs and larvae were found on various rodents and a bat.

Genetic evidence for conspecificity between Dermacentor marginatus and Dermacentor niveus.

Ticks are hematophagous arthropods transmitting several harmful human and animal pathogens like viruses, Rickettsia, bacteria, and protozoa. The identification and speciation of ticks were normally performed in Iran using identification key of Arthur (1960) and Kaiser and Hoogstraal (J Parasitol 49:130-139, 1963) or on the basis of morphological characteristic keys recommended by Walker et al. (2003). Although these identification keys are well prepared, but there are in some cases due to the strong overlapping characteristics between species like Dermacentor marginatus and Dermacentor niveus accompanied with serious problems. D. marginatus and D. niveus have been intermittently used synonymously and there is no a generally agreement with the specification of these species. To find out more about these two species, we have analyzed the complete nucleotide sequence of ITS-2 region. Interestingly, we found indeed a sequence homology of 99% between nucleotide sequence of ITS-2 region of D. marginatus and D. niveus. Since the nucleotide sequence of ITS-2 region of D. marginatus in Iran has 98% sequence homology to the other in GenBank registered ITS-2 sequence of D. marginatus, and the morphological characteristics between both examined species showed minimal differences, therefore we believe that the D. marginatus and D. niveus could belong to the same species and 1% differences in nucleotide sequence of ITS-2 region between these two species can be understand as an intra-species polymorphism.

Abnormal morphology of an adult Rocky Mountain wood tick, Dermacentor andersoni (Acari: Ixodidae).

During a collection of ticks from vegetation in March 2006, a single adult male Rocky Mountain wood tick, Dermacentor andersoni (Stiles, 1908), was collected that exhibited unique morphological anomalies, including the absence of a leg on the right side of the body. Coxa IV on the right side also was missing in this specimen. Such teratological changes have not been reported previously for D. andersoni.