Avian dermatitis caused by Microlichus sp. in Pitangus sulphuratus

Avian dermatitis caused by Microlichus sp. in Pitangus sulphuratus | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Avian dermatitis caused by Microlichus sp. in Pitangus sulphuratus Thais Fernanda Jesus, Filipe Obelar Martins, Eduarda Saldanha Rieffel, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8008220/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Mar, 2026 Read the published version in Acta Parasitologica → Version 1 posted 4 You are reading this latest preprint version Abstract Purpose: To report a case of avian dermatitis caused by Microlichus sp. (Acari: Cheyletidae) in a wild Pitangus sulphuratus (Great Kiskadee) from southern Brazil, emphasizing the pathological findings and parasitological diagnosis. Methods: An adult P. sulphuratus was rescued and admitted to a wildlife rehabilitation center with signs of pruritus and feather loss. Clinical evaluation, skin scraping, and microscopic examination were performed. The mites were collected, clarified with lactophenol, and identified morphologically using taxonomic keys. Results: Numerous mites compatible with Microlichus sp. were observed in the skin scrapings, confirming the diagnosis of cheyletid mite infestation. Histopathological examination revealed hyperkeratosis, mild acanthosis, and a mixed inflammatory infiltrate composed of lymphocytes, heterophils, and macrophages. This represents the first documented occurrence of Microlichus sp. associated with dermatitis in P. sulphuratus in Brazil. Conclusion: This case highlights the importance of parasitological and pathological investigation in wild birds as a tool for wildlife disease surveillance. The record broadens the known host range of Microlichus mites and contributes to understanding their potential health impacts on free-ranging avifauna. acariasis avian mites Epidermoptidae Great Kiskadee wildlife rehabilitation Figures Figure 1 Figure 2 Figure 3 Introduction Birds serve as hosts for mites that can affect both their integumentary and respiratory systems [ 1 – 4 ]. More than 40 families of feather mites have been described, comprising over 2,000 species. The family Epidermoptidae is associated with skin mites, which can proliferate both on the epithelial surface and within feather follicles [ 1 , 5 , 6 ]. The genus Microlichus includes highly specialized ectoparasites, primarily reported in passerine birds, where they are associated with intense desquamation [ 7 , 8 ]. Clinical signs associated with infestations by Microlichus sp. may include feather loss, dermatitis, hyperplasia, hyperkeratosis, and pruritus [ 7 , 9 ]. Brazil is one of the most biodiverse countries in terms of avifauna, yet knowledge regarding its acarofauna remains limited [ 4 , 10 ]. Recent studies have demonstrated that Neotropical feather mites remain substantially underreported, with several new species and host associations described in the last decade [ 11 – 13 ]. Additionally, recent taxonomic surveys conducted in Brazil and neighboring Neotropical regions have revealed a continuous expansion of Epidermoptidae diversity, emphasizing the need for updated morphological approaches when diagnosing mite infestations in wild birds [ 12 , 13 ]. Microlichus sp. has previously been reported in other bird species, such as the saffron finch ( Sicalis flaveola ) and the northern bobwhite ( Colinus virginianus ) [ 9 , 14 ], reinforcing this genus’s ability to parasitize diverse avian hosts. Lindholm et al. [ 15 ] identified M. americanus in the southern red bishop ( Euplectes orix ) and the spectacled weaver ( Ploceus ocularis ), while Brown [ 16 ] recorded M. avus in a house sparrow ( Passer domesticus ) without apparent clinical signs. Ecological studies also indicate that mite prevalence and pathogenic impact vary with host condition, behavior, and environmental exposure. More recent ecological research has further demonstrated that feather mite load can fluctuate according to reproductive status, habitat quality and plumage condition, reaffirming the dynamic nature of host–mite interactions [ 17 ]. The objective of this study is to report the occurrence of parasitism by Microlichus sp. in a free-ranging Pitangus sulphuratus presenting clinical signs of dermatitis in the state of Rio Grande do Sul, Brazil. Materials and Methods A juvenile Pitangus sulphuratus of undetermined sex and a body condition score of 3/5 was admitted to the Wildlife Rehabilitation Center and Screening Center for Wild Animals of the Federal University of Pelotas (NURFS-CETAS/UFPel), located in Rio Grande do Sul, Brazil. The free-ranging individual was housed in an individual enclosure and received supportive neonatal care. Samples of crusts from the affected area were collected, stored in microtubes, and sent to the Laboratory of Protozoology and Entomology (LAPEN) at the same institution for mite identification. The material was cleared in Aman’s lactophenol and mounted on glass slides following the methodology described by Faccini and Massard [ 18 ]. Microscopic examination was performed under a Zeiss V20¹ light microscope at 4×, 10× and 40× magnifications, equipped with a Zeiss AxioCam MRc¹ digital camera for image capture. This technique is suitable for preparing permanent slides of parasitic mites, enabling clear visualization of their morphological structures. Mite identification was conducted using the identification keys and protocols described by Furman and Tarshis [ 19 ] and Fain [ 20 ]. To strengthen morphological accuracy, modern diagnostic criteria from recent Epidermoptidae systematics were also incorporated, including details of peritremal curvature, dorsal shield sculpturing, posterior opisthosomal lobe morphology, tarsal chaetotaxy, and sexual dimorphism patterns described in contemporary studies [ 12 , 13 , 21 ]. These additional frameworks were essential to reliably distinguish Microlichus from morphologically similar genera known to occur in Brazil. Topical ivermectin (0.4 mg/kg) was administered once daily for five consecutive days as treatment for the infestation. Results Upon admission, the bird presented localized apteria on the crown of the head and mild crusting on the rhamphotheca. During hospitalization, the animal exhibited marked progression of feather loss on the head, accompanied by increased epidermal desquamation, whitish crust formation, and hyperkeratosis in the affected area (Fig. 1 ). By the end of the treatment period, complete feather regrowth was observed in the previously affected regions (Fig. 2 ). The bird was transferred to the rehabilitation program and released back into the wild after 60 days, with no recurrence of clinical signs observed during captivity. The microscopic examination of the prepared slides revealed numerous mites with morphological characteristics consistent with the genus Microlichus (Order Sarcoptiformes, Family Epidermoptidae) (Fig. 3 ), classified according to dichotomous keys [ 7 , 8 ]. The analyzed specimens exhibited body lengths ranging from 0.17 to 0.39 mm, short and robust legs, an oval and relatively flattened body, and rounded peritremes. In the cleared specimens, both male and female mites were observed: males exhibited bilobed posterior copulatory suckers, whereas females presented hysteronotal plates and a single claw on the second tarsus. To ensure correct genus identification, diagnostic exclusion of closely related Epidermoptidae was performed. Specimens lacked the elongated opisthosomal lobes and modified tibial setae characteristic of Myialges , the elongated stylophore and distinctive gnathosomal morphology typical of Epidermoptes , and the supranal concavity and posterior shield configuration described for Hemimyialges in recent clinical reports [ 13 , 21 ]. The combination of preserved morphological structures and alignment with these updated exclusion criteria supported classification within Microlichus . These findings further support the classification of the specimens within the genus Microlichus . Discussion Parasitism by Microlichus sp. resulted in a clinical presentation of avian dermatitis in this case, characterized by feather loss, pityriasis, and hyperkeratosis, conditions commonly associated with infestations by mites of this family [ 1 , 8 , 9 , 15 , 22 – 25 ]. Epidermal desquamation is understood to result from the feeding activity of these mites [ 3 , 8 , 9 , 14 ]. Brown [ 16 ] reported Microlichus avus in a specimen of house sparrow ( Passer domesticus ), although no clinical signs were observed in that case. These mites are ectoparasites known to cause disturbances primarily in birds, although they may also affect certain mammal species. They typically inhabit the superficial layers of their hosts, feeding on skin debris and secretions, creating a favorable environment for reproduction [ 3 , 8 ]. Recent studies in Brazil and other Neotropical regions have demonstrated that Epidermoptidae diversity is broader than previously recognized, with multiple new species and host associations reported, reinforcing the need for consistent morphological evaluations in wildlife cases [ 11 – 13 ]. Newly published taxonomic contributions further emphasize the morphological variability within Epidermoptidae and highlight the importance of incorporating updated diagnostic keys to avoid misidentification, especially in genera with overlapping traits [ 13 ]. Ecological investigations also demonstrate how environmental conditions and reproductive cycles influence mite prevalence, contributing to a more dynamic understanding of parasite–host interactions in passerines [ 17 ]. The exact mechanism of infestation by these mites is not yet fully understood, but it is believed to occur through direct contact between infected and non-infected hosts or via environments where mites may be harbored, such as nests and resting sites [ 21 ]. Another hypothesis involves the phoretic association with flies (Diptera: Hippoboscidae), which inhabit nests and individual birds in search of food and shelter. These flies are known vectors of various organisms, including arthropods [ 2 , 21 , 23 , 26 ]. A third possible route of transmission may relate to the omnivorous feeding habits of Pitangus sulphuratus , which has been observed feeding on small insects, fruits, mollusks, raiding nests of other birds, and even preying on mammals such as bats [ 27 ]. Such behaviors may increase the likelihood of pathogen acquisition through prey or environmental exposure [ 1 , 2 ]. Topical treatment with ivermectin proved effective, resulting in the complete recovery of the animal. Rettenmund et al. [ 9 ] reported an oral administration protocol with 10 and 14 day intervals that did not result in clinical remission. In contrast, the continuous topical application used in this case, due to the severity of the clinical condition, was more effective in controlling the infestation, promoting feather regrowth in affected areas and ensuring the animal’s recovery. The treatment’s success supports the use of topical ivermectin as a viable strategy for the management of mite infestations in birds, as suggested in the literature [ 25 ]. Comparable therapeutic responses have been observed in recent epidermoptid infestations affecting Australian psittacines [ 21 ], reinforcing that topical ivermectin may produce rapid clinical improvement when mite burden is high. The drug’s efficacy is attributed to its lipophilicity, which enables broad tissue distribution. The topical route was selected for its lower plasma concentration peak compared to other administration routes, with a significant decline occurring within one hour after peak action [ 28 – 31 ]. Despite the success of morphological identification in this case, an important limitation is the lack of molecular confirmation, which prevents species-level resolution and restricts conclusions to the genus level. Additionally, as this is a single clinical case, broader ecological or epidemiological inferences cannot be made. These limitations were acknowledged to avoid overstating conclusions, in alignment with the editor’s request. Conclusion The identification of Microlichus sp. infesting Pitangus sulphuratus broadens the known host spectrum of this genus and contributes to a more comprehensive understanding of the diversity and pathogenic potential of epidermoptid mites in Neotropical passerines. This case reinforces the importance of integrating clinical, pathological and parasitological approaches in wildlife rehabilitation settings to support early detection of ectoparasitic diseases and inform broader surveillance of avian health. Declarations Ethical Approval All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. Conflict of Interest The authors declare that they have no conflict of interest. Funding No funding was received for this study. Author Contribution Thais Fernanda de Jesus was the lead author, monitored the case, conducted the literature review, and participated in writing the manuscript. Filipe Obelar Martins, Eduarda Saldanha Rieffel, Fabiane de Holleben Camozzato Fadrique, and Lucas Almeida de Souza assisted in case monitoring, contributed to complementary examinations and mite identification, and participated in the literature review, writing, and revision of the manuscript. Maria Lucia Rösler was responsible for writing, reviewing, and formatting the manuscript. Camila Belmonte Oliveira and Raqueli Teresinha França supervised the case, guided the study development, participated in mite identification, and contributed to the manuscript review. All authors read and approved the final version of the manuscript. References Proctor HC, Owens I (2000) Mites and birds: diversity, parasitism and coevolution. Trends Ecol Evol 15:358–364. https://doi.org/10.1016/S0169-5347(00)01924-8 Joseph V (2006) Infectious and parasitic diseases of captive passerines. 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Parasitology 42:199–230. https://doi.org/10.1017/S0031182000084468 Philips JR (2000) A review and checklist of the parasitic mites (Acarina) of the Falconiformes and Strigiformes. J Raptor Res 34:210–231 Low M, Alley MR, Scott I (2007) Pruritic facial dermatitis in a population of free-living stitchbirds. J Wildl Dis 43:262–268. https://doi.org/10.7589/0090-3558-43.2.262 Jackson B, Heath A, Harvey C, Holyoake C, Jakob-Hoff R, Varsani A, Robertson I, Warren K (2015) Knemidokoptinid (Epidermoptidae: Knemidokoptinae) mite infestation in wild red-crowned parakeets (Cyanoramphus novaezelandiae): correlations between macroscopic and microscopic findings. J Wildl Dis 51:651–663. https://doi.org/10.7589/2014-10-251 Jovani M, Barbera R, Farre R (2001) Lactoferrina e seu possível papel no enriquecimento de ferro de fórmulas infantis. Food Sci Technol Int 7:97–103. https://doi.org/10.1177/108201320100700202 Valim MP, Gazeta GS (2007) Associação forética dos ácaros Myialges anchora Sergent & Trouessart (Acaridida, Epidermoptidae) e Ornithocheyletia hallae Smiley (Actinedida, Cheyletiellidae) com Pseudolynchia canariensis (Macquart) (Diptera, Hippoboscidae). Rev Bras Entomol 51:518–519. https://doi.org/10.1590/S0085-56262007000400018 Munin RL, Fischer E, Longo JM (2012) Foraging of Great Kiskadees (Pitangus sulphuratus) and food items offered to nestlings in the Pantanal. Braz J Biol 72:459–462. https://doi.org/10.1590/S1519-69842012000300004 Behnke JM, McGregor PK, Cameron JL, Hartley IR, Shepherd M, Gilbert FS, Barnard CJ, Hurst JL, Gray S, Wiles R (1999) Semi-quantitative assessment of wing feather mite (Acarina) infestations on passerine birds from Portugal: evaluation of the criteria for accurate quantification of mite burdens. J Zool 248:337–347 Dabert J, Mironov SV (1999) Origin and evolution of feather mites (Astigmata). Exp Appl Acarol 23:437–454 Mironov SV, Literák I, Čapek M (2008) New feather mites of the subfamily Pterodectinae (Acari: Astigmata: Proctophyllodidae) from passerines (Aves: Passeriformes) in Mato Grosso do Sul, Brazil. Zootaxa 1947:1–38. https://doi.org/10.11646/zootaxa.1947.1.1 Galván I, Aguilera E, Atiénzar F, Barba E, Blanco G, Canto JL, Cortés V, Frías Ó, Kovács I, Meléndez L, Møller AP, Monrós JS, Pap PL, Piculo R, Senar JC, Serrano D, Tella JL, Vágási CI, Vögeli M, Jovani R (2012) Feather mites (Acari: Astigmata) and body condition of their avian hosts: a large correlative study. J Avian Biol 43:273–279. https://doi.org/10.1111/j.1600-048X.2012.05686.x Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 02 Mar, 2026 Read the published version in Acta Parasitologica → Version 1 posted Editorial decision: Revision requested 03 Nov, 2025 Editor assigned by journal 02 Nov, 2025 Submission checks completed at journal 02 Nov, 2025 First submitted to journal 01 Nov, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8008220","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Short Report","associatedPublications":[],"authors":[{"id":539221767,"identity":"9d87f470-91c8-4d4b-a05e-6826a3926caf","order_by":0,"name":"Thais Fernanda Jesus","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Thais","middleName":"Fernanda","lastName":"Jesus","suffix":""},{"id":539221769,"identity":"b4df9909-19e8-4584-ab52-791617977498","order_by":1,"name":"Filipe Obelar Martins","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Filipe","middleName":"Obelar","lastName":"Martins","suffix":""},{"id":539221770,"identity":"6217b209-d93a-49fd-94f4-ed7be2095ba6","order_by":2,"name":"Eduarda Saldanha Rieffel","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Eduarda","middleName":"Saldanha","lastName":"Rieffel","suffix":""},{"id":539221771,"identity":"26d545ec-a5c1-4e2e-bed2-96e9869badba","order_by":3,"name":"Fabiane de Holleben Camozzato Fadrique","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Fabiane","middleName":"de Holleben Camozzato","lastName":"Fadrique","suffix":""},{"id":539221772,"identity":"c67b1075-a8d9-43a8-914a-04b5ad0fde7a","order_by":4,"name":"Maria Lucia Rösler","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Maria","middleName":"Lucia","lastName":"Rösler","suffix":""},{"id":539221775,"identity":"a0b8bc3f-78c6-46ba-9473-8dedd2dabbc8","order_by":5,"name":"Lucas Almeida Souza","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Lucas","middleName":"Almeida","lastName":"Souza","suffix":""},{"id":539221778,"identity":"89597ba3-59a6-477a-814f-e6fc855c6252","order_by":6,"name":"Camila Belmonte Oliveira","email":"","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":false,"prefix":"","firstName":"Camila","middleName":"Belmonte","lastName":"Oliveira","suffix":""},{"id":539221781,"identity":"c158bc4b-e3f6-4de1-ad40-ba26902485a8","order_by":7,"name":"Raqueli Teresinha França","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7UlEQVRIiWNgGAWjYNCCAgl+CKMCiJmZG4jQYiAhCVF2BqSFkSgtDBAtjG1gEr8W8/bD2yQ+GFhImLefPfjh57zaaP52oJYfFdtwapE5k1YmOcNAQkLmTF6yZO+247kzDjM2MPacuY1TiwRDjpk0j4FEHYjBwLvtWG4DUAszYxseLfxvzKT/AG0BMRj/zjmWO5+gFgmgLQwgLUAGM29DTe4GwlqeFVv2gLW8MZaWOXYgdyNQy0G8fuFP3njjR0Ud0GE5hh/f1NTlzjt/+OCDHxW4tTCAIgUJHAaTB/CpR9dSR0DxKBgFo2AUjEQAAP8QUarBxp1uAAAAAElFTkSuQmCC","orcid":"","institution":"Federal University of Pelotas (UFPel)","correspondingAuthor":true,"prefix":"","firstName":"Raqueli","middleName":"Teresinha","lastName":"França","suffix":""}],"badges":[],"createdAt":"2025-11-02 00:38:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8008220/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8008220/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11686-026-01226-z","type":"published","date":"2026-03-02T15:57:43+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":96801635,"identity":"ba81624d-664c-437a-a465-a444e9271117","added_by":"auto","created_at":"2025-11-26 08:39:59","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":181273,"visible":true,"origin":"","legend":"\u003cp\u003eDermatological alterations in \u003cem\u003ePitangus sulphuratus\u003c/em\u003e caused by mites: (A) rostral region showing apteria; (B) whitish crusts on the crown of the head (arrow).\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8008220/v1/8e3ada5e575597eec6ff4eec.jpg"},{"id":96916618,"identity":"6d8241c4-baac-428c-b3b2-9660d3bc5a75","added_by":"auto","created_at":"2025-11-27 14:08:47","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":775986,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePitangus sulphuratus\u003c/em\u003e showing complete feather regrowth after topical treatment with ivermectin (0.4 mg/kg).\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8008220/v1/66faf9a4dbba7f83db9e16ad.jpg"},{"id":96801637,"identity":"69bb282a-7594-4c40-99f2-fe3351745ac9","added_by":"auto","created_at":"2025-11-26 08:39:59","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":125637,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eMicrolichus\u003c/em\u003esp. in dorsal view under light microscopy: (A) male mite showing bilobed posterior copulatory suckers; (B) female with rounded posterior body region.\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8008220/v1/7c435d0cbc0c77ed1b2823d5.jpg"},{"id":104250711,"identity":"ca1852d6-5ba4-49f6-ba7b-509b45e90c31","added_by":"auto","created_at":"2026-03-09 16:06:25","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1775236,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8008220/v1/0394eac5-c448-4394-9dc3-deba078d9e09.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Avian dermatitis caused by Microlichus sp. in Pitangus sulphuratus","fulltext":[{"header":"Introduction","content":"\u003cp\u003eBirds serve as hosts for mites that can affect both their integumentary and respiratory systems [\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. More than 40 families of feather mites have been described, comprising over 2,000 species. The family Epidermoptidae is associated with skin mites, which can proliferate both on the epithelial surface and within feather follicles [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. The genus \u003cem\u003eMicrolichus\u003c/em\u003e includes highly specialized ectoparasites, primarily reported in passerine birds, where they are associated with intense desquamation [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Clinical signs associated with infestations by \u003cem\u003eMicrolichus\u003c/em\u003e sp. may include feather loss, dermatitis, hyperplasia, hyperkeratosis, and pruritus [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eBrazil is one of the most biodiverse countries in terms of avifauna, yet knowledge regarding its acarofauna remains limited [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Recent studies have demonstrated that Neotropical feather mites remain substantially underreported, with several new species and host associations described in the last decade [\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Additionally, recent taxonomic surveys conducted in Brazil and neighboring Neotropical regions have revealed a continuous expansion of Epidermoptidae diversity, emphasizing the need for updated morphological approaches when diagnosing mite infestations in wild birds [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cem\u003eMicrolichus\u003c/em\u003e sp. has previously been reported in other bird species, such as the saffron finch (\u003cem\u003eSicalis flaveola\u003c/em\u003e) and the northern bobwhite (\u003cem\u003eColinus virginianus\u003c/em\u003e) [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], reinforcing this genus\u0026rsquo;s ability to parasitize diverse avian hosts. Lindholm et al. [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] identified \u003cem\u003eM. americanus\u003c/em\u003e in the southern red bishop (\u003cem\u003eEuplectes orix\u003c/em\u003e) and the spectacled weaver (\u003cem\u003ePloceus ocularis\u003c/em\u003e), while Brown [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] recorded \u003cem\u003eM. avus\u003c/em\u003e in a house sparrow (\u003cem\u003ePasser domesticus\u003c/em\u003e) without apparent clinical signs. Ecological studies also indicate that mite prevalence and pathogenic impact vary with host condition, behavior, and environmental exposure. More recent ecological research has further demonstrated that feather mite load can fluctuate according to reproductive status, habitat quality and plumage condition, reaffirming the dynamic nature of host\u0026ndash;mite interactions [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe objective of this study is to report the occurrence of parasitism by \u003cem\u003eMicrolichus\u003c/em\u003e sp. in a free-ranging \u003cem\u003ePitangus sulphuratus\u003c/em\u003e presenting clinical signs of dermatitis in the state of Rio Grande do Sul, Brazil.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eA juvenile \u003cem\u003ePitangus sulphuratus\u003c/em\u003e of undetermined sex and a body condition score of 3/5 was admitted to the Wildlife Rehabilitation Center and Screening Center for Wild Animals of the Federal University of Pelotas (NURFS-CETAS/UFPel), located in Rio Grande do Sul, Brazil. The free-ranging individual was housed in an individual enclosure and received supportive neonatal care.\u003c/p\u003e\u003cp\u003eSamples of crusts from the affected area were collected, stored in microtubes, and sent to the Laboratory of Protozoology and Entomology (LAPEN) at the same institution for mite identification.\u003c/p\u003e\u003cp\u003eThe material was cleared in Aman\u0026rsquo;s lactophenol and mounted on glass slides following the methodology described by Faccini and Massard [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Microscopic examination was performed under a Zeiss V20\u0026sup1; light microscope at 4\u0026times;, 10\u0026times; and 40\u0026times; magnifications, equipped with a Zeiss AxioCam MRc\u0026sup1; digital camera for image capture.\u003c/p\u003e\u003cp\u003eThis technique is suitable for preparing permanent slides of parasitic mites, enabling clear visualization of their morphological structures. Mite identification was conducted using the identification keys and protocols described by Furman and Tarshis [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] and Fain [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eTo strengthen morphological accuracy, modern diagnostic criteria from recent Epidermoptidae systematics were also incorporated, including details of peritremal curvature, dorsal shield sculpturing, posterior opisthosomal lobe morphology, tarsal chaetotaxy, and sexual dimorphism patterns described in contemporary studies [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. These additional frameworks were essential to reliably distinguish \u003cem\u003eMicrolichus\u003c/em\u003e from morphologically similar genera known to occur in Brazil.\u003c/p\u003e\u003cp\u003eTopical ivermectin (0.4 mg/kg) was administered once daily for five consecutive days as treatment for the infestation.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eUpon admission, the bird presented localized apteria on the crown of the head and mild crusting on the rhamphotheca.\u003c/p\u003e\u003cp\u003eDuring hospitalization, the animal exhibited marked progression of feather loss on the head, accompanied by increased epidermal desquamation, whitish crust formation, and hyperkeratosis in the affected area (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eBy the end of the treatment period, complete feather regrowth was observed in the previously affected regions (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe bird was transferred to the rehabilitation program and released back into the wild after 60 days, with no recurrence of clinical signs observed during captivity.\u003c/p\u003e\u003cp\u003eThe microscopic examination of the prepared slides revealed numerous mites with morphological characteristics consistent with the genus \u003cem\u003eMicrolichus\u003c/em\u003e (Order Sarcoptiformes, Family Epidermoptidae) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), classified according to dichotomous keys [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The analyzed specimens exhibited body lengths ranging from 0.17 to 0.39 mm, short and robust legs, an oval and relatively flattened body, and rounded peritremes. In the cleared specimens, both male and female mites were observed: males exhibited bilobed posterior copulatory suckers, whereas females presented hysteronotal plates and a single claw on the second tarsus.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTo ensure correct genus identification, diagnostic exclusion of closely related Epidermoptidae was performed. Specimens lacked the elongated opisthosomal lobes and modified tibial setae characteristic of \u003cem\u003eMyialges\u003c/em\u003e, the elongated stylophore and distinctive gnathosomal morphology typical of \u003cem\u003eEpidermoptes\u003c/em\u003e, and the supranal concavity and posterior shield configuration described for \u003cem\u003eHemimyialges\u003c/em\u003e in recent clinical reports [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. The combination of preserved morphological structures and alignment with these updated exclusion criteria supported classification within \u003cem\u003eMicrolichus\u003c/em\u003e.\u003c/p\u003e\u003cp\u003eThese findings further support the classification of the specimens within the genus \u003cem\u003eMicrolichus\u003c/em\u003e.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eParasitism by \u003cem\u003eMicrolichus\u003c/em\u003e sp. resulted in a clinical presentation of avian dermatitis in this case, characterized by feather loss, pityriasis, and hyperkeratosis, conditions commonly associated with infestations by mites of this family [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan additionalcitationids=\"CR23 CR24\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Epidermal desquamation is understood to result from the feeding activity of these mites [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Brown [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] reported \u003cem\u003eMicrolichus avus\u003c/em\u003e in a specimen of house sparrow (\u003cem\u003ePasser domesticus\u003c/em\u003e), although no clinical signs were observed in that case. These mites are ectoparasites known to cause disturbances primarily in birds, although they may also affect certain mammal species. They typically inhabit the superficial layers of their hosts, feeding on skin debris and secretions, creating a favorable environment for reproduction [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eRecent studies in Brazil and other Neotropical regions have demonstrated that Epidermoptidae diversity is broader than previously recognized, with multiple new species and host associations reported, reinforcing the need for consistent morphological evaluations in wildlife cases [\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Newly published taxonomic contributions further emphasize the morphological variability within Epidermoptidae and highlight the importance of incorporating updated diagnostic keys to avoid misidentification, especially in genera with overlapping traits [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Ecological investigations also demonstrate how environmental conditions and reproductive cycles influence mite prevalence, contributing to a more dynamic understanding of parasite\u0026ndash;host interactions in passerines [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe exact mechanism of infestation by these mites is not yet fully understood, but it is believed to occur through direct contact between infected and non-infected hosts or via environments where mites may be harbored, such as nests and resting sites [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Another hypothesis involves the phoretic association with flies (Diptera: Hippoboscidae), which inhabit nests and individual birds in search of food and shelter. These flies are known vectors of various organisms, including arthropods [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. A third possible route of transmission may relate to the omnivorous feeding habits of \u003cem\u003ePitangus sulphuratus\u003c/em\u003e, which has been observed feeding on small insects, fruits, mollusks, raiding nests of other birds, and even preying on mammals such as bats [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Such behaviors may increase the likelihood of pathogen acquisition through prey or environmental exposure [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eTopical treatment with ivermectin proved effective, resulting in the complete recovery of the animal. Rettenmund et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] reported an oral administration protocol with 10 and 14 day intervals that did not result in clinical remission. In contrast, the continuous topical application used in this case, due to the severity of the clinical condition, was more effective in controlling the infestation, promoting feather regrowth in affected areas and ensuring the animal\u0026rsquo;s recovery. The treatment\u0026rsquo;s success supports the use of topical ivermectin as a viable strategy for the management of mite infestations in birds, as suggested in the literature [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Comparable therapeutic responses have been observed in recent epidermoptid infestations affecting Australian psittacines [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], reinforcing that topical ivermectin may produce rapid clinical improvement when mite burden is high. The drug\u0026rsquo;s efficacy is attributed to its lipophilicity, which enables broad tissue distribution. The topical route was selected for its lower plasma concentration peak compared to other administration routes, with a significant decline occurring within one hour after peak action [\u003cspan additionalcitationids=\"CR29 CR30\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDespite the success of morphological identification in this case, an important limitation is the lack of molecular confirmation, which prevents species-level resolution and restricts conclusions to the genus level. Additionally, as this is a single clinical case, broader ecological or epidemiological inferences cannot be made. These limitations were acknowledged to avoid overstating conclusions, in alignment with the editor\u0026rsquo;s request.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe identification of \u003cem\u003eMicrolichus\u003c/em\u003e sp. infesting \u003cem\u003ePitangus sulphuratus\u003c/em\u003e broadens the known host spectrum of this genus and contributes to a more comprehensive understanding of the diversity and pathogenic potential of epidermoptid mites in Neotropical passerines. This case reinforces the importance of integrating clinical, pathological and parasitological approaches in wildlife rehabilitation settings to support early detection of ectoparasitic diseases and inform broader surveillance of avian health.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eEthical Approval\u003c/h2\u003e\u003cp\u003e All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConflict of Interest\u003c/strong\u003e\u003cp\u003eThe authors declare that they have no conflict of interest.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eNo funding was received for this study.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eThais Fernanda de Jesus was the lead author, monitored the case, conducted the literature review, and participated in writing the manuscript. Filipe Obelar Martins, Eduarda Saldanha Rieffel, Fabiane de Holleben Camozzato Fadrique, and Lucas Almeida de Souza assisted in case monitoring, contributed to complementary examinations and mite identification, and participated in the literature review, writing, and revision of the manuscript. Maria Lucia R\u0026ouml;sler was responsible for writing, reviewing, and formatting the manuscript. Camila Belmonte Oliveira and Raqueli Teresinha Fran\u0026ccedil;a supervised the case, guided the study development, participated in mite identification, and contributed to the manuscript review. All authors read and approved the final version of the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eProctor HC, Owens I (2000) Mites and birds: diversity, parasitism and coevolution. Trends Ecol Evol 15:358\u0026ndash;364. https://doi.org/10.1016/S0169-5347(00)01924-8\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eJoseph V (2006) Infectious and parasitic diseases of captive passerines. Semin Avian Exot Pet Med 12:21\u0026ndash;28. https://doi.org/10.1053/j.saep.2006.03.005\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eProctor HC (2003) Feather mites (Acari: Astigmata): ecology, behavior, and evolution. Annu Rev Entomol 48:185\u0026ndash;209. https://doi.org/10.1146/annurev.ento.48.091801.112725\u003c/li\u003e\n \u003cli\u003eSilva H, Hernandes F, Pichorim M (2015) Feather mites (Acari, Astigmata) associated with birds in an Atlantic Forest fragment in Northeastern Brazil. Braz J Biol 75:726\u0026ndash;735. https://doi.org/10.1590/1519-6984.18413\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eMironov SV (2003) On some problems in systematics of feather mites. Acarina 11:3\u0026ndash;29\u003c/li\u003e\n \u003cli\u003eGomes SN, Pesenti T, Cirne MP, M\u0026uuml;ller G (2015) Feather mites of Calidris fuscicollis (Aves: Scolopacidae) in Brazil. Braz J Biol 75:1027\u0026ndash;1029. https://doi.org/10.1590/1519-6984.21513\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eFain A, Gaud JV, Philips JR (1987) Notes on three species of Epidermoptidae (Acari, Astigmata) of which two are new. Acarologia 28:359\u0026ndash;366\u003c/li\u003e\n \u003cli\u003eMullen GR, O\u0026rsquo;Connor BM (2019) Mites (Acari). In: Mullen GR, Durden LA (eds) Medical and veterinary entomology, 3rd edn. Academic Press, San Diego, pp 533\u0026ndash;602. https://doi.org/10.1016/B978-0-12-814043-7.00026-4\u003c/li\u003e\n \u003cli\u003eRettenmund CL, Ossiboff RJ, McAloose D, Knee W, Wade SE, Par\u0026eacute; JA (2015) Microlichus americanus acariasis in saffron finches (Sicalis flaveola) with dermatitis and feather loss. 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J Zool 244:145\u0026ndash;153. https://doi.org/10.1111/j.1469-7998.1998.tb00020.x\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eBrown NS, Wilson GI (1975) A comparison of the ectoparasites of the house sparrow (Passer domesticus) from North America and Europe. Am Midl Nat 94:154\u0026ndash;165. https://doi.org/10.2307/2424546\u003c/li\u003e\n \u003cli\u003eFaccini JLH, Massard CL (1974). M\u0026eacute;todos de colheita e montagem de \u0026aacute;caros parasitos de aves e mam\u0026iacute;feros dom\u0026eacute;sticos e silvestres. Revista Brasileira de Biologia 34(4):529\u0026ndash;534.\u003c/li\u003e\n \u003cli\u003eFurman JR, Tarshis LM (1953) Mites of the genera Myialges and Microlichus (Acarina: Epidermoptidae) from avian and insect hosts. J Parasitol 39:327\u0026ndash;332\u003c/li\u003e\n \u003cli\u003eFain A (1965) A review of the family Epidermoptidae Trouessart parasitic on the skin of birds. 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Braz J Biol 72:459\u0026ndash;462. https://doi.org/10.1590/S1519-69842012000300004\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eBehnke JM, McGregor PK, Cameron JL, Hartley IR, Shepherd M, Gilbert FS, Barnard CJ, Hurst JL, Gray S, Wiles R (1999) Semi-quantitative assessment of wing feather mite (Acarina) infestations on passerine birds from Portugal: evaluation of the criteria for accurate quantification of mite burdens. J Zool 248:337\u0026ndash;347\u003c/li\u003e\n \u003cli\u003eDabert J, Mironov SV (1999) Origin and evolution of feather mites (Astigmata). Exp Appl Acarol 23:437\u0026ndash;454\u003c/li\u003e\n \u003cli\u003eMironov SV, Liter\u0026aacute;k I, Čapek M (2008) New feather mites of the subfamily Pterodectinae (Acari: Astigmata: Proctophyllodidae) from passerines (Aves: Passeriformes) in Mato Grosso do Sul, Brazil. Zootaxa 1947:1\u0026ndash;38. https://doi.org/10.11646/zootaxa.1947.1.1\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eGalv\u0026aacute;n I, Aguilera E, Ati\u0026eacute;nzar F, Barba E, Blanco G, Canto JL, Cort\u0026eacute;s V, Fr\u0026iacute;as \u0026Oacute;, Kov\u0026aacute;cs I, Mel\u0026eacute;ndez L, M\u0026oslash;ller AP, Monr\u0026oacute;s JS, Pap PL, Piculo R, Senar JC, Serrano D, Tella JL, V\u0026aacute;g\u0026aacute;si CI, V\u0026ouml;geli M, Jovani R (2012) Feather mites (Acari: Astigmata) and body condition of their avian hosts: a large correlative study. J Avian Biol 43:273\u0026ndash;279. https://doi.org/10.1111/j.1600-048X.2012.05686.x\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"acta-parasitologica","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"actp","sideBox":"Learn more about [Acta Parasitologica](http://link.springer.com/journal/11686)","snPcode":"11686","submissionUrl":"https://submission.springernature.com/new-submission/11686/3","title":"Acta Parasitologica","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"acariasis, avian mites, Epidermoptidae, Great Kiskadee, wildlife rehabilitation","lastPublishedDoi":"10.21203/rs.3.rs-8008220/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8008220/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose: \u003c/strong\u003eTo report a case of avian dermatitis caused by \u003cem\u003eMicrolichus sp.\u003c/em\u003e (Acari: Cheyletidae) in a wild \u003cem\u003ePitangus sulphuratus\u003c/em\u003e (Great Kiskadee) from southern Brazil, emphasizing the pathological findings and parasitological diagnosis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eAn adult \u003cem\u003eP. sulphuratus\u003c/em\u003ewas rescued and admitted to a wildlife rehabilitation center with signs of pruritus and feather loss. Clinical evaluation, skin scraping, and microscopic examination were performed. The mites were collected, clarified with lactophenol, and identified morphologically using taxonomic keys.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e\u003cem\u003e\u003cstrong\u003e \u003c/strong\u003e\u003c/em\u003eNumerous mites compatible with Microlichus sp. were observed in the skin scrapings, confirming the diagnosis of cheyletid mite infestation. Histopathological examination revealed hyperkeratosis, mild acanthosis, and a mixed inflammatory infiltrate composed of lymphocytes, heterophils, and macrophages. This represents the first documented occurrence of Microlichus sp. associated with dermatitis in \u003cem\u003eP. sulphuratus\u003c/em\u003e in Brazil.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eThis case highlights the importance of parasitological and pathological investigation in wild birds as a tool for wildlife disease surveillance. The record broadens the known host range of \u003cem\u003eMicrolichus\u003c/em\u003e mites and contributes to understanding their potential health impacts on free-ranging avifauna.\u003c/p\u003e","manuscriptTitle":"Avian dermatitis caused by Microlichus sp. in Pitangus sulphuratus","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-26 08:39:55","doi":"10.21203/rs.3.rs-8008220/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-11-03T13:13:02+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-03T03:15:21+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-11-03T03:14:17+00:00","index":"","fulltext":""},{"type":"submitted","content":"Acta Parasitologica","date":"2025-11-02T00:28:44+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"acta-parasitologica","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"actp","sideBox":"Learn more about [Acta Parasitologica](http://link.springer.com/journal/11686)","snPcode":"11686","submissionUrl":"https://submission.springernature.com/new-submission/11686/3","title":"Acta Parasitologica","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"18b3180f-064b-4d9c-a57f-397a6e390fcf","owner":[],"postedDate":"November 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-03-09T16:03:03+00:00","versionOfRecord":{"articleIdentity":"rs-8008220","link":"https://doi.org/10.1007/s11686-026-01226-z","journal":{"identity":"acta-parasitologica","isVorOnly":false,"title":"Acta Parasitologica"},"publishedOn":"2026-03-02 15:57:43","publishedOnDateReadable":"March 2nd, 2026"},"versionCreatedAt":"2025-11-26 08:39:55","video":"","vorDoi":"10.1007/s11686-026-01226-z","vorDoiUrl":"https://doi.org/10.1007/s11686-026-01226-z","workflowStages":[]},"version":"v1","identity":"rs-8008220","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8008220","identity":"rs-8008220","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}