• Animal Systematics, Evolution and Diversity
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• v.5 no.1
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• pp.13-24
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• 1989

Specimens of spider mites parasiting on conifer trees were collected from Korea during the period from May, 1986 to June, 1988. As a result, seven species belonging to the tribe Tetranychini, subfamily Tetranychinae, family Tetranychidae were identified as follows: 1. Panonychus citri(McGregor, 1916), *2. Oligonychus clavatus(Ehara,1959), *. O.hondoensis(Ehara,1954), *4. O.pustulosus Ehara, 1962, 5. O.karamatus(Ehara, 1956), 6. O.perditus Pritchard and Baker, 1955, 7. O. ununguis(Jacobi, 1905). Of which, three species with asterisk are newly recorded from Korea.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.151-155
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• 1999

Biological control of Tetranychus kanzawai by Phytoseiulus persimilis on the Angelica utilis was done in 'walk-in' plastic tunnels. The population of T. kanzawai nymphs and adults per 4 cm2 in damaged leaf decreased from 25 mites on July 22 after 25 predatory mites per m2 were released on July 23 to 0.4 mites on September 9 and then rose to 9.3 mites on October 16, 1997. Phytoseiulus persimilis could suppress T. kanzawai to low population level from August 13 to October 1.

• Parasites, Hosts and Diseases
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• v.58 no.4
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• pp.445-450
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• 2020

Trombiculid "chigger" mites (Acari) are ectoparasites that feed blood on rodents and another animals. A crosssectional survey was conducted in 7 ecosystems of southern Vietnam from 2015 to 2016. Chigger mites were identified with morphological characteristics and assayed by polymerase chain reaction for detection of rickettsiaceae. Overall chigger infestation among rodents was 23.38%. The chigger index among infested rodents was 19.37 and a mean abundance of 4.61. A total of 2,770 chigger mites were identified belonging to 6 species, 3 genera, and 1 family, and pooled into 141 pools (10-20 chiggers per pool). Two pools (1.4%) of the chiggers were positive for Orientia tsutsugamushi. Ricketsia spp. was not detected in any pools of chiggers. Further studies are needed including a larger number and diverse hosts, and environmental factors to assess scrub typhus.

• Parasites, Hosts and Diseases
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• v.59 no.3
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• pp.319-324
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• 2021

Incidence of tsutsugamushi disease (scrub typhus) caused by Orientia tsutsugamushi, is steadily increasing. It is a mite-borne disease transmitted by chigger mites. In this study, the chigger mites were collected from field small mammals in Hwaseong-si (city), Gyeonggi-do (province), Korea, 2019 and 2020. The field small mammals captured were 56 Apodemus agrarius (94.9%) and 3 Crocidura lasiura (5.1%). A total of 7,531 chigger mites were collected from the captured small mammals. Using PCR test, 153 chigger mite pools were examined and 17 pools were reported positive for O. tsutsugamushi. The O. tsutsugamushi were identified to 5 strains; Jecheon strain was most prevalent, followed by Boryong strain. The other strains were OI011, Taguchi, and Shimokoshi. Collectively, these results provide essential regional information on mite-borne tsutsugamushi disease in the Hwaseong-si, and further contribute to bring awareness and rapid diagnosis for the tsutsugamushi disease.

• The Korean Journal of Soil Zoology
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• v.3 no.2
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• pp.78-90
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• 1998

This study was carried out from May 1993 to October 1994 to examine diversity of oribatid mites in Namsan and Kwangreung coniferous forests, which were considered to receive different degrees of environmental pressures. Also, environmental factors (pH of soil and rainfall, litter depth, organic matter) were recorded in the two forests. The pH of soil and rainfall were not different between the two forests, but litter depth and organic matter were significantly higher in Namsan than in Kwangreung (p<0.05). The dominant families (>5% of the total densities) were Scheloribatidae(27.3%), Galumnidae(13.4%), Oppiidae (9.9%), Hypochthonidae(7.6%), Suctobelbidae(6.6%), Euphthiracaridae(5.9%) in Namsan and Ceratozetidae(25.9%), Mycobatidae (14.2%), Oppiidae(14.2%), Galumnidae(11.4%), Astegistidae(8.7%) in Kwangreung. The numbers of species were significantly higher in Kwangreung (103 spp.) than in Namsan (74 spp.)(p<0.05). The total densities of oribatid mites were more abundant in Kwangreung (8,709 ind.) than in Namsan (5,899 ind.) and the difference was significant for density in litter layer (p<0.05).

• Animal Systematics, Evolution and Diversity
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• v.3 no.2
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• pp.64-116
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• 1987

The purpose of the present paper is to record taxonomic notes on several Korean spider mites. The specimens on which this study is based were collected by the authors during the period from May, 1986 to June, 1987. The following species are the spider mites concerned in this paper. 1. Panonychus citri (McGregor), 2. Eotetranychus populi Koch, 3. Eotetranychus smithi Pritchard and Baker, 4. Shizotetranychus bambusae Reck, 5. Schizotetranychus celarius (Banks), 6. Shizotetranychus leguminosus Ehara, 7. Oligonychus orthis Rimando, 8. Tetranychus ranzawai Kishida, 9. Tetranychus phaselus Ehara, 10. Tetranychus trancatus Ehara , 11. Tetranychus vienensis Zacher, 12. Tetranychus urticae Koch . Among them, eight species with asterisk are newly recorded from Korea . In addition, empodiums of pretarsus were carefully observed and enzyme patterns by electrophoresis were compared on some species in order induce their systematic inter-relationship at either species or generic level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.749-752
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• 2006

The house dust mites are well known to the most important causative allergens of major allergic diseases like pediatric asthma, allergic rhinitis or atopic dermatitis. This study was done for assessment of naphthalene effect against breeding suppression of the house dust mites. Twenty live adult house dust mites(Dermatophaogoides pteronyssinus) were each inoculated on mixed culture media containing 0 mg (control), 1mg, 2 mg, 3 mg, 5 mg, and 10 mg naphthalene and incubated at $25^{\circ}C$ with a relative humidity of 75%. After 4 weeks mean number of live house dust mites were 191.5, 24.3, 1.3, 1.3, 0, and 0, respectively. Above results showing that the naphthalene can suppress of breeding the house dust mites in vitro.

• Parasites, Hosts and Diseases
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• v.55 no.5
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• pp.555-559
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• 2017

Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China ($114-112^{\circ}E$, $34-38^{\circ}N$), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.73-79
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• 2006

We evaluated the efficacy of health education in reducing indoor arthropod allergens in Seoul. The mite control measures comprised the use of mite-proof mattress and pillow coverings, regular washing of potentially infested materials, maintenance of a low humidity, removal of carpets, and frequent vacuum cleaning. Cockroach control measures included trapping, application of insecticides, and protecting food. Of 201 homes enrolled in October 1999, 63 volunteers were included in a 2-year follow-up survey between April 2000 and January 2002. Before intervention, the density of mites/g of dust varied greatly; 27.1/g in children's bedding, 20/g in adult bedding, 7.2/g on the floors of children's bedrooms, 6.8/g in sofas, 5.9/g on the floors of adult's bedrooms, 3.9/g on living room floors, 3.7/g in carpets, and 1.9 mites/g on kitchen floors. The predominant mite species and house percentages infested were; Dermatophagoides farinae $93\%$, D. pteronyssinus $9\%$, and Tyrophagus putrescentiae $8\%$. Comparing 1999 and 2001 infestations, before and after 25 mo of education, mite abundance was reduced by $98\%$, from 23.7 to 0.57 mites/g of dust. In 1999, cockroaches were detected in $62\%$ homes: $36\%$ Blattella germanica and $35\%$ Periplaneta spp., including $9\%$ double infestations of B. germanica and P. americana. Following intervention, cockroach infestation rates decreased to $22\%$ of houses in 2000 and $23\%$ in 2001. We conclude that continuous and repetitive health education resulted in the effective control of domestic arthropods.

• Parasites, Hosts and Diseases
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• v.46 no.4
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• pp.273-278
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• 2008

Mites in the genus Chorioptes cause a mild form of skin disease in both domestic and wild ruminants. In July 2006, dermatitis characterized by alopecia, marked lichenification, accumulation of crust, and fissuring was recognized in 14 out of 200 Holstein dairy cattle raised in the cattle farm of the National Institute of Animal Science in Cheonan, Republic of Korea. Skin lesions were distributed mainly over the tail base, and sacral and perineal regions. Microscopic examinations of skin scraping samples from severely affected areas revealed numerous mites of all developmental stages. Morphologically, pedicels of the mites were short and unjointed. The tarsal suckers occurred on the pedicels of all the legs in the male worm and on the first, second, and fourth pair of legs in the adult female worm. A single long seta at the tarsus of legs III and the length of legs II being about twice as long as legs IV in adult male mites were observed. Arising anterior to the inner-most spatulate seta was a short seta with an average of $26.4{\pm}5.8{\mu}m$ in length. Also, the length of setae #4 on the opisthosomal lobes was relatively short. Based on these observations, the mites were identified as Choriptes texanus. Although the chorioptic mange may not influence the mortality rate in the affected farm, reports indicate that a decline in milk production can be observed. This is the first report of chorioptic infestation in a cattle farm from Korea.