Bacterial pathogens' screening in Brazilian chigger mites (Trombidiformes: Trombiculidae), with the first report of 'Candidatus Rickettsia colombianensi'-like in avian-associated chiggers.

Chiggers are larval ectoparasites of the Trombiculidae that can transmit pathogens to their hosts. In this study, chiggers collected from birds in Brazil were morphologically identified as Blankaartia sinnamaryi, Eutrombicula batatas, Eutrombicula daemoni, Eutrombicula goeldii, Eutrombicula tinami, and Parasecia gilbertoi. For these specimens, a beginning attempt at molecular identification were also provided, as well as, were genetically screened to detect bacterial pathogens. The species B. sinnamaryi and E. tinami were positive for Rickettsia felis-like and 'Candidatus Rickettsia colombianensi'-like, respectively. For the other agents (Anaplasmataceae, Borrelia spp. and Orientia tsutsugamushi), the tests were negative. This is the first report of 'Ca. R. colombianensi'-like and the second record of R. felis-like in chigger collected on birds from Brazil.

Reinstatement of Eutrombicula butantanensis (Fonseca, 1932) (Trombidiformes: Trombiculidae).

Eutrombicula Ewing is currently represented with more than 80 species worldwide parasitizing amphibians, reptiles, birds, and mammals. In the present study, we examined the type series and additional material of two Neotropical chigger's species: Eutrombicula butantanensis (Fonseca) and E. ophidica (Fonseca). Eutrombicula butantanensis (Fonseca) was previously synonymized with E. alfreddugesi (Oudemans). However, we are proposing the reinstatement of E. butantanensis as a valid species. Besides that, we are proposing that E. ophidica is a junior synonym of E. butantanensis. Beyond the morphological similarities, E. butantanensis and E. ophidica were initially described to the state of São Paulo, Brazil, and were accidentally collected parasitizing the skin of a human. Besides that, we are increasing the knowledge about E. butantanensis on Brazil's national territory, recording new locality and host associations.

Rudnicula goffi n. sp. (Acariformes: Trombiculidae) from the diadem leaf-nosed bat Hipposideros diadema (Geoffroy) (Chiroptera: Hipposideridae) on Bali, Indonesia.

A new species of chigger mite, Rudnicula goffi n. sp., is described from the diadem leaf-nosed bat Hipposideros diadema (Geoffroy) (Hipposideridae) caught in the Goa Peteng Cave on Bali (Indonesia). The new species differs from the closely related species by the presence of scutum with AL windows, lateral scutal margins with cuticular striations and fSt = 2 + 2 + 2. A list of all available records of Rudnicula species is provided. The genus is restricted to the tropics of Southeast Asia, Australia, Melanesia, and the subtropics of eastern Asia. A key to the known species of Rudnicula based on the morphology of the larvae is also provided.

Research Progress on Leptotrombidium deliense.

This article reviews Leptotrombidium deliense, including its discovery and nomenclature, morphological features and identification, life cycle, ecology, relationship with diseases, chromosomes and artificial cultivation. The first record of L. deliense was early in 1922 by Walch. Under the genus Leptotrombidium, there are many sibling species similar to L. deliense, which makes it difficult to differentiate L. deliense from another sibling chigger mites, for example, L. rubellum. The life cycle of the mite (L. deliense) includes 7 stages: egg, deutovum (or prelarva), larva, nymphochrysalis, nymph, imagochrysalis and adult. The mite has a wide geographical distribution with low host specificity, and it often appears in different regions and habitats and on many species of hosts. As a vector species of chigger mite, L. deliense is of great importance in transmitting scrub typhus (tsutsugamushi disease) in many parts of the world, especially in tropical regions of Southeast Asia. The seasonal fluctuation of the mite population varies in different geographical regions. The mite has been successfully cultured in the laboratory, facilitating research on its chromosomes, biochemistry and molecular biology.

A Revised Checklist of Chigger Mites (Acari: Trombiculidae) From Thailand, with the Description of Three New Species.

Chigger mites of Thailand were studied on the basis of larvae collected from 19 small mammal species (17 species of Rodentia, 1 species of Erinaceomorpha, and 1 species of Scandentia) and revision of published data. Samples of 38 trombiculid species were collected from 11 provinces. Three new species were described: Trombiculindus kosapani sp. nov., Helenicula naresuani sp. nov., and Walchia chavali sp. nov. Ten species were recorded in Thailand for the first time: Leptotrombidium sialkotense Vercammen-Grandjean and Langston, 1976; Leptotrombidium subangulare Wen and Xiang, 1984; Leptotrombidium tenompaki Stekolnikov, 2013; Leptotrombidium turdicola Vercammen-Grandjean and Langston, 1976; Leptotrombidium yunlingense Yu, Yang, Zhang and Hu, 1981; Lorillatum hekouensis Yu, Chen and Lin, 1996; Helenicula pilosa (Abonnenc and Taufflieb, 1957); Gahrliepia xiaowoi Wen and Xiang, 1984; Walchia minuscuta Chen, 1978; and Walchia ventralis (Womersley, 1952). In all, 99 chigger mite species were considered; the presence of 93 species was established in Thailand by original data or properly documented records in the scientific literature. Evidence for 64 species records of 147 from a previous checklist of Thai chiggers (Tanskul 1993) remains unknown. Distribution of chigger species by geographical regions of Thailand is discussed.

Catenotaenia dendritica (Cestoda: Catenotaeniidae) and Three Ectoparasite Species in the Red Squirrel, Sciurus vulgaris, from Cheongju, Korea.

Parasites are recorded from the red squirrel, Sciurus vulgaris, from Cheongju, the Republic of Korea. A total of 5 road-killed squirrels were thoroughly examined for internal and external parasites from November 2011 to May 2014. Total 4 parasite species, including 1 tapeworm and 3 ectoparasite species were recovered. They were morphologically identified as Catenotaenia dendritica (Cestoda: Catenotaeniidae), Hirstionyssus sciurinus, Leptotrombidium pallidum, and Ceratophyllus (Monopsyllus) indages. Among them, C. dendritica and H. sciurinus are recorded for the first time in the Korean parasite fauna. In addition, the possibility that the red squirrel could act as a reservoir host for a zoonotic disease like tsutsugamushi disease with L. pallidum as its vector has been raised.

A Checklist of Chigger Mites (Acari: Trombiculidae and Leeuwenhökiidae) From Taiwan, With Descriptions of Three New Species.

Scrub typhus is a lethal human disease transmitted by larval trombiculid mites (i.e., chiggers) that have been infected with the rickettsia Orientia tsutsugamushi. In total, 21 chigger species are known from Taiwan. We update the checklist of chiggers of Taiwan based on an intensive survey of shrew and rodent hosts in grasslands and agricultural fields in lowland Taiwan, coupled with surveys of forests in one mountainous site and an opportunistic examination of submitted host specimens. Three new species of chiggers, Gahrliepia (Gateria) lieni sp. n., Gahrliepia (Gateria) minuta sp. n., and Gahrliepia (Gateria) yilanensis sp. n., as well as 23 newly recorded chigger species, were discovered. Accordingly, recorded chigger species of Taiwan more than doubled from 21 to 47 species. Two new species and nine newly recorded chigger species were discovered in forests in one mountainous site in northeastern Taiwan, suggesting that many more chigger species may be uncovered, particularly in mountainous Taiwan. Further studies should also investigate O. tsutsugamushi infection in different chigger species to assess its risks to human health.

Host-associated differences in morphometric traits of parasitic larvae Hirsutiella zachvatkini (Actinotrichida: Trombiculidae).

Examination of host-associated variation in the chigger mite Hirsutiella zachvatkini (Schluger) revealed morphological differences among larvae infesting sympatric hosts: Apodemus agrarius, Apodemus flavicollis and Myodes glareolus. The analysis included 61 variables of larvae obtained from their gnathosoma, idiosoma and legs (measurements and counts). Statistically significant differences were observed for metric characters of the legs as opposed to the scutum. In view of the conspecificity of the mites, supported by comparison of COI gene products obtained from larvae and laboratory-reared deutonymphs, the observed variation is attributed to phenotypic plasticity. The knowledge of larval morphology, including intraspecific variation of metric characters, supported by molecular and host range data, places H. zachvatkini among the most comprehensively defined members of Trombiculidae.

A new species of chigger mite (acari: trombiculidae) from rodents in southwest China.

This paper describes a new species of chigger mite (ACARI: Trombiculidae), Gahrliepia cangshanensis n. sp., from rodents in southwest China. The specimens were collected from Yunnan red-backed voles, Eothenomys miletus (Thomas, 1914), and a Chinese white-bellied rat, Niviventer confucianus (Milne-Edwards, 1871) in Yunnan Province. The new species is unique mainly in its number of dorsal setae (n=21), and it has the following features: fT (formula of palpotarsus)=4B (B=branched), fp (formula of palpal seta)=B/N/N/N/B (N=naked), a broad tongue-shaped scutum with an almost straight posterior margin, and 17 PPLs (posterior posterolateral seta) with a length of 36-43 µm. This chigger mite may also infect other rodent hosts and may be distributed in other localities.

A new genus and two new species of chigger mites (Acari: Trombiculidae) from the Laotian rock-rat Laonastes aenigmamus Jenkins, Kilpatrick, Robinson & Timmins (Rodentia: Diatomyidae).

A new chigger mite genus Laotrombicula n. g. and two new species, Laotrombicula khunboromi n. sp. (type-species) and L. fangumi n. sp., are described from the Laotian rock-rat Laonastes aenigmamus Jenkins, Kilpatrick, Robinson & Timmins (Rodentia: Diatomyidae). The new genus is most similar to Trombiculindus Radford, 1948 and Leptotrombidium Nagayo, Miyagawa, Mitamura & Imamura, 1916 and differs from these genera by having the scutum of subhexagonal or semicircular shape vs widely rectangular; pinnatifid dorsocentral idiosomal setae vs foliaceous in Trombiculindus and unexpanded in Leptotrombidium; and by the presence of serrated longitudinal crests in the middle part of scutum.

A New Species of Chigger (Acari: Trombiculidae) from Indonesia and Current Differentiation of Trombicula Berlese, 1905 Sensu Stricto Group.

BACKGROUND: Two new species of chiggers in the two genera (Chiroptella Vercammen-Grandjean, 1960 and Rudnicula Vercammen-Grandjean, 1964) have been described in Indonesia since 2020. The checklist of all known bat-infesting chiggers has also been compiled for Indonesia. It summarizes 16 species in 9 genera of chiggers parasitizing 12 bat species belonging to 5 families collected on 8 Indonesian islands. Nine specimens collected in 2020 on Nusa Penida Island were not included in the checklist because of their uncertain taxonomy. In the current paper, we resolve the taxonomy of these specimens belonging to Trombicula sensu stricto group. We also revise the existing characters of this group and provide new characters helping with the clear definition of this taxa. METHODS: Hosts and chiggers were captured in February 2020 in Nusa Penida Islands in Indonesia using standard bat-capturing and parasite-collecting methods. For the specimens examined in this study were provided drawings, measurements, and microscopy images. This type material is deposited in the Slovak and Czech National museums. RESULTS: In the paper, we describe a new species parasitizing diadem leaf-nosed bat in the Goa Peteng cave on Nusa Penida Island (Lesser Sunda Islands, East Indonesia). This new species differs from all related species by the presence of a very long tarsala I (S1). A key to the larvae of all seven known Trombicula s. s. species is provided. The differentiation of Trombicula s. s. group is based on leg segmentation fsp = 6.6.6, rugose scutum with complete AM, AL and PL setation, and fT = 5B, 5BN or 4B2N. CONCLUSION: A new species within the genus Trombicula, group minor has been described. The new species also increases the number of known chiggers in Indonesia and the number of species parasitizing the host species Hipposideros diadema. Trombicula s. s. has also been revised and more clearly defined.

Feline trombiculosis: a retrospective study in 72 cats.

BACKGROUND: Trombiculosis is the infestation of a host by the larval form of mites belonging to the Trombiculidae family. Few data are available regarding this infestation in cats. HYPOTHESIS/OBJECTIVES: The aim of this retrospective study was to report data, clinical signs, diagnostic and therapeutic features of feline trombiculosis. METHODS: Clinical records of cats presented for dermatological examination or annual vaccination in Italy, from 2002 to 2012, were retrospectively searched using the key words trombiculosis, cat and Neotrombicula. RESULTS: Seventy-two indoor/outdoor domestic short-hair cats with infestation by Neotrombicula autumnalis were enrolled. Pruritus was reported by the owners in 43% of cases, while 57% of cats were asymptomatic. The most common clinical signs included sudden onset of pruritus and the appearance of orange-coloured granules on the skin. Mites were found incidentally in 12 cats. The larvae were localized in multiple sites in 68% of cases. The most frequently affected area was the ear (80.5% of cases). Mites were more often identified in autumn (41 cases). Eleven cats were diagnosed during winter, 13 in spring and seven in summer. CONCLUSIONS AND CLINICAL IMPORTANCE: This retrospective study suggests that feline trombiculosis is probably underestimated as a cause of pruritus and dermatological lesions. Epidemiological data regarding this infestation in cats are still lacking, and it will be interesting to perform a multicentre study to increase knowledge of this disease.

Leptotrombidium (Acari: Trombiculidae) of the World.

The chigger mite genus Leptotrombidium Nagayo, Miyagawa, Mitamura and Imamura, 1916 is reviewed using literature data. For 340 larval species brief diagnoses, synonymy, data on type hosts and type localities are provided. The genus is divided into species-groups based on morphological evidence enabling easier establishment of group-membership of un-known specimens in the future. Some species groups are supported by a hierarchical cluster analysis with multiscale boot-strap resampling applied to a matrix including 335 species and geographic morphotypes and 19 standard quantitative characters. Six new species from mammalian hosts are described: L. aenigmami sp. nov., L. abramovi sp. nov., L. tikhon-ovi sp. nov., L. bochkovi sp. nov., L. laoense sp. nov., and L. megaloti sp. nov. from Laos. Seven names created by Ver-cammen-Grandjean and Langston (1976) for infrasubspecific entities are applied to species with the same descriptions: Leptotrombidium tenompaki sp. nov., L. kinabalui sp. nov., L. megabodense sp. nov., L. minului sp. nov., L. ului sp. nov., L. megalangati sp. nov., and L. saigoni sp. nov. A new replacement name is proposed: L. ushi nom. nov. pro L. hsui Wu, Yang and Li, 1999 (praeocc. Yu, Yang and Gong, 1986). Nineteen new synonyms and 7 new combinations are proposed: Leptotrombidium (= Hsuella Wang, Li and Shi, 1989, syn. nov.; = Leptotrombidium (Monosigmum) Wen, 2001, syn. nov.), L. deliense (Walch, 1922) (= L. deliense sinense Wen and Chen, 1984, syn. nov.; = L. deliense microsetosa Zhao, Tang and Mo, 1986, syn. nov.), L. sialkotense Vercammen-Grandjean and Langston, 1976 (= L. jishoum Wen, Li, Zhang and Liao, 1988, syn. nov.), L. imphalum Vercammen-Grandjean and Langston, 1976 (= L. imphalum sabahense Vercam-men-Grandjean and Langston, 1976, syn. nov.; = L. chiangraiensis Tanskul and Linthicum, 1997, syn. nov.), L. wenense Wu, Wen, Yang and Wu, 1982 (= L. kaohuense Li, Wang and Chen, 1997, syn. nov.), L. longimedian Brown, 1992 (= L. mindanensis Brown, 1992, syn. nov.), L. silvaticum Hushcha and Schluger, 1967 (= L. pakistanum Vercammen-Grandjean and Langston, 1976, syn. nov.), L. cricethrionis Wen, Sun and Sun, 1984 (= L. rusticum Yu, Yang and Gong, 1986, syn. nov.), L. intermedium (Nagayo, Mitamura and Tamiya, 1920) (= Trombicula (L.) daisen Kumada and Sasa, 1953, syn. nov.; = Trombicula hiranumai Kanda, 1942, syn. nov.), L. fletcheri (Womersley and Heaslip, 1943) (= L. fletcheri fran-colini Wen and Xiang, 1984b, syn. nov.), L. apertum Kudryashova, 1979 (= L. sorosi Kharadov, 1995, syn. nov.; = L. tolaicus Kharadov, 2000, syn. nov.), L. turdicola Vercammen-Grandjean and Langston, 1976 (= L. muntiaci Xiang and Wen, 1984d, syn. nov.; = L. suense Wen, 1984g, syn. nov.), L. paradux Vercammen-Grandjean and Langston, 1976 (= L. montanum Stekolnikov, 2004, syn. nov.), L. hubeiense (Wang, Li and Shi, 1989) comb. nov. from Hsuella, L. dunqingi (Liu, Xiang and Ma, 2003) comb. nov. from Hsuella, L. nainae (Kharadov, 1990) comb. nov. from Montivagum, L. mon-golicum (Kudryashova, 1988) comb. nov. from Montivagum, L. kunitzkyi (Kudryashova, 1988) comb. nov. from Monti-vagum, L. alaicum (Kharadov, 1994) comb. nov. from Montivagum, and Lorillatum nudisensillum (Yu, Gong and Tao, 1981) comb. nov. from Leptotrombidium. A key to Leptotrombidium species is provided.

A revision of the chigger mite genus Paratrombicula Goff & Whitaker, 1984 (Acari: Trombiculidae), with the description of two new species.

The monotypic chigger mite genus Paratrombicula Goff & Whitaker, 1984 is expanded to include five species. Two new species of chiggers, parasitising iguanid lizards in Chile, Paratrombicula chilensis n. sp. and P. goffi n. sp., are described, and two species, P. neuquenensis (Goff & Gettinger, 1995) n. comb. and Paratrombicula plaumanni (Brennan & Jones, 1964) n. comb., are transferred to this genus from Parasecia Loomis, 1966 and Neotrombicula Hirst, 1925, respectively. A key to the species of Paratrombicula is presented.

Annotated checklist of chigger mites (Trombidiformes: Leeuwenhoekiidae, Trombiculidae and Walchiidae) in Sri Lanka.

Chigger mites (Leeuwenhoekiidae, Trombiculidae, and Walchiidae) are parasites of any terrestrial vertebrate. The present study updates the list of chigger mite (Trombiculidae, Leeuwenhoekiidae, and Walchiidae) species recorded from Sri Lanka along with taxonomic classification based on previous investigations since 1946 to date and our observations in western and southern parts of the country. This checklist listed 15 species in 9 genera within the three chigger families. For now, murid species were the host most sampledparasitized by chiggers in Sri Lanka. However, further studies are required to increase the diversity of chigger mites in Sri Lanka and probably the description of new species, which will be possible with morphological and molecular characterization.

Bat-Infesting Chiggers (Trombiculidae) in Indonesia: Current Review, Distribution, and Hosts with Three New Records and their Morphometric Data.

PURPOSE: Even though the taxonomy of bat-infesting chiggers has been studied extensively, information about the distribution and morphological variability of many species is still lacking. In fact, the only available distribution records for several species are their type localities. The purpose of this paper is to broaden the knowledge of the Indonesian group. METHODS: Hosts and chiggers were captured from April 2018 to March 2020 in Bali and Nusa Penida Islands in Indonesia by using standard bat-capturing and parasite-collecting methods. A list of bat-infesting chiggers in Indonesia was compiled by searching the public databases using specific keywords. RESULTS: When compared with already published data on type specimens, the physical measurements and morphology of Whartonia diosi, W. maai and Grandjeana sinensis revealed only minor differences that fell within intraspecific variability of the mentioned species. Two species (W. diosi and G. sinensis) are recorded here for the first time outside of their type localities (Panay Island in the Philippines and China) and, in both cases, represent the first records for Indonesia. The checklist summarizes all 16 species in 9 genera of bat-infesting chiggers collected from 12 bat species belonging to 5 families all collected on 8 Indonesian islands. CONCLUSION: Indonesia comprises more than 17,000 islands, is home to over 200 bat species, and harbors hundreds of still undiscovered caves. With such a huge potential for chigger diversity and endemism, it is likely that our results document only a fraction of the actual diversity.

Chigger Mites (Acariformes: Trombiculidae) of Chiloé Island, Chile, With Descriptions of Two New Species and New Data on the Genus Herpetacarus.

Three species of chigger mites are recorded in our collections from four species of cricetid rodents on Chiloé Island (southern Chile, Los Lagos Region), an area endemic to scrub typhus (Orientia sp.). Two species are described as new-Herpetacarus (Abonnencia) eloisae sp. nov. and Quadraseta chiloensis sp. nov. One species, Paratrombicula goffiStekolnikov and González-Acuña 2012, is for the first time recorded on a mammal host (one species of cricetid rodent), and its distribution is extended to the Los Lagos Region of Chile. The genus ProschoengastiaVercammen-Grandjean, 1967 is synonymized with the subgenus Herpetacarus (Abonnencia)Vercammen-Grandjean, 1960, and four new combinations are established: Herpetacarus (Abonnencia) herniosa (Brennan and Jones, 1961), comb. nov., Herpetacarus (Abonnencia) insolita (Brennan and Jones, 1961), comb. nov., Herpetacarus (Abonnencia) macrochaeta (Brennan and Jones, 1961), comb. nov., and Herpetacarus (Abonnencia) antarctica (Stekolnikov and Gonzalez-Acuña, 2015), comb. nov.

Contribution to the Taxonomy and Host-Relations of the Genus Serratacarus (Trombidiformes: Trombiculidae).

The genus SerratacarusGoff and Whitaker 1984, currently includes only two species, Serratacarus dietzi Goff and Whitaker, 1994 and Serratacarus lasiurus Goff and Whitaker, 1994, which were recorded on cricetid rodents from natural reserve areas of Brazil. Here, we provide a review of the morphological characters for both species and synonymize of the species Trombewingia brasiliensisGoff and Gettinger, 1991 with S. lasiurus. Additionally, we provide new locality records for both species and the first record for S. dietzi on southeastern four-eyed opossum, Philander frenatus Olfers, 1818 (Didelphimorphia, Didelphidae).

Two New Species of Chiggers (Trombidiformes: Trombiculidae) From Brazil.

Chigger mites are parasites of terrestrial vertebrates, including humans. Here, we describe two new species belonging to the American genera Colicus Brennan and Parasecia Loomis. Both species were described on the base of museum specimens originated from Minas Gerais State, Brazil, Colicus barrosbattestiae n. sp. parasitizing the rodent, Oligoryzomys fornesi and Parasecia jacinaviciusi n. sp. parasitizing the marsupial, Monodelphis domestica.

A New Genus and Species of Chiggers (Trombidiformes: Leeuwenhoekiidae) From Peru.

South American chiggers have historically been poorly studied, and this has continued into present times. Of the 33 genera in the family Leeuwenhoekiidae Womersley, only Odontacarus Ewing and Sasacarus Brennan & Jones have been reported in Peru. Here, we describe a new genus, Peruacarus n. gen., and a new species, Peruacarus anthurium n. sp., parasitizing Koford's grass mouse, Akodon kofordi Myers & Patton, in Peru.