First report of gynandromorphism in Rhipicephalus microplus (Acari: Ixodidae) in El Salvador

First report of gynandromorphism in Rhipicephalus microplus (Acari: Ixodidae) in El Salvador | 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 Research Article First report of gynandromorphism in Rhipicephalus microplus (Acari: Ixodidae) in El Salvador Marvin Stanley Rodriguez Aquino, Esther Noemí Juárez Alvarado, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9115111/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Gynandromorphism is a developmental anomaly characterized by the simultaneous presence of male and female morphological attributes within the same individual. This study documents the first case of gynandromorphism in the cattle tick Rhipicephalus microplus (Canestrini 1888) in El Salvador. The specimen was collected from a bovine belonging to the Experimental and Practical Station of the Faculty of Agronomic Sciences of the University of El Salvador, located in the municipality of San Luis Talpa, Department of La Paz. The reported gynandromorph of R. microplus exhibits bilateral symmetry, displaying primarily female characteristics on the left side and male characteristics on the right. Gynandromorphism ticks Rhipicephalus microplus Figures Figure 1 Introduction Gynandromorphism, also known as sexual chimerism, is a biological condition that can originate through diverse mechanisms, such as hormonal alterations (Graves, Patten et al. 1996), genetic anomalies during chromosomic separation (Zhao, McBride et al. 2010) or fecundation of binuclear oocytes as described by Blanchard & Descimon, 1988. When the male and female sexual characteristics distribution occurs in a comparable way in both hemi-bodies, the organism is classified as bilateral gynandromorph. If the alteration emerges during more advanced stages in the embryonic development or cellular division, the symmetry may be irregular or only partial, reaching more complex patterns expressed with axial configurations or mosaicism, which can evolve from different etiologic processes (Blanchard and Descimon 1988). Gynandromorphism is not an uncommon developmental abnormality in ticks. This phenomenon has been previously documented in some free-living genera of ticks, particularly Amblyomma sp and Hyalomma sp (Prusinski, Mertins et al. 2015). In terms of gynandromorphism reports among the genus Rhipicephalus in Neotropical regions, there are some documented cases among brow dog tick, Rhipicephalus sanguineus sensu lato (Pereira and Castro 1945, Labruna, Ribeiro et al. 2002, Salceda-Sánchez, Sánchez-Montes et al. 2020). Similarly, there have been instances reported in R. (Boophilus) microplus, corresponding to a category classified as semi-divided gynandromorphism called “ginandromorfismo semi-partido”, where both male and female characteristics are expressed as irregular features, mostly as presenting male parts on a female body (Kumar and Nagar 1979). This short communication describes the first reported instance of gynandromorphism in ticks in El Salvador in R. microplus . Methods Starting in 2021, the University of El Salvador’s Health Discovery and Investigation Center, (Centro de Investigación y Desarrollo en Salud), began a tick surveillance initiative aimed at detecting veterinary and medically important pathogens. In October 2025, colleagues were executing a systematic tick collection from cattle and the surrounding fields at the university’s agricultural research facility (Estación Experimental y de Prácticas, Facultad de Ciencias Agronómicas), in the municipality of San Luis Talpa, Departamento de La Paz (13°28'22.4"N, 89°05'46.1"W). During the sampling, an unusual specimen was found attached to a Holstein Brown Swiss cattle ( Bos primigenius taurus ), that was removed and preserved in a 70% ethanol and 5% glycerol-containing vial. Taxonomic identification was performed following the Garrapatas Ixodidae de Panamá key (Bermúdez, Apanaskevich et al. 2018). The specimen was examined and photographed using a stereomicroscope Leica EZ4E (Leica Microsystems Inc, Wetzlar, Germany). Results The specimen collected was taxonomically identified as R. microplus , with evidence of dorsally presenting gynandromorphism, with a bilateral asymmetric division. This transversal division goes from the base of the capitulum to the posterior end of the tick, presenting mostly female characteristics on the left side, and male characteristics on the right side (Figure 1A). The tick presents a scutum, characteristic of female ticks. The ventral zone contains an anal groove slightly over the female side, whereas the genital pore is found medially located. It is worth noting that there is a tendency of these medial features to lean towards the male side due to the engorgement of the female side (Figure 1B). The male side shows adanal plates, often seen in male ticks; there is no caudal pedunculus (Figure 1D). On the male side, coxae present short, pointed spurs on the first coxa; comparatively, on the female side, these are short and rounded (Figure 1C). Spiracular plates can be observed on both sides (Figure 1E). The capitulum does not show division differences, unlike the idiosoma (Figure 1F). The basis capituli is small, hexagonal, anchored to the scutum, and presents shorter palps than the hypostome, characteristic of females. Discussion Evidence of gyandromorphism in R. microplus (previously, Boophilus microplus ) is limited to a few instances and has never reported in El Salvador. An earlier report from Loomis and Stone found a R. microplus collected from a Shorthorn calf with gynandromorphism in Australia(Loomis and Stone 1970). This individual showed female characteristics on the left side and male characteristics on the right side, although it did not have a complete bilateral division of both sexes, showing predominantly male characteristics. Similarly, our findings showed asymmetric distribution, with mostly predominant female characteristics. In contrast, a different gynandromorphic R. microplus specimen was described in a collection from a Shri Bareilly Gowshala calf (Kumar and Nagar 1979). This Indian tick possessed a scutum in its normal location and a partial conscutum in a posterior lateral position to the left of the idiostoma. Although some of the features were male, the genital pore showed only female characteristics, while in our report the division between both sexes split the genital pore. In a recent review of a large tick collection from the Instituto Conmemorativo Gorgas de Estudios de la Salud in Panama, the team revised 6,624 hard ticks and identified 255 specimens with morphological anomalies. Their observations suggested that gynandromorphism and other general abnormalities are less frequent than local malformations; only two Amblyomma dissimile specimens showed gynandromorphism(Domínguez and Bermúdez 2020). It has been suggested that gynandromorphism is more common in the genus Amblyomma, although this could be influenced by a general underreporting of morphological anomalies in ticks(Balinandi, Mugisha et al. 2019). While it seems to be found relevant for infectious agents(Domínguez and Bermúdez 2020), it does not seem to affect the tick’s ability to find a bloodmeal as evidenced by gynandromorph specimens collected from cattle. While the relevance of this feature remains understudied, reporting these anomalies is important for the scientific community. Future research should continue focusing on the morphological diversity of medically and veterinary relevant arthropods in El Salvador, with the goal to better understand the biological impact and the possible ecological and epidemiological implications it carries. References Balinandi, S., et al. (2019). "General and local morphological anomalies in Amblyomma lepidum (Acari: Ixodidae) and Rhipicephalus decoloratus infesting cattle in Uganda." Journal of Medical Entomology 56 (3): 873-877. Bermúdez, S., et al. (2018). "Garrapatas Ixodidae de Panamá." Secretaría Nacional de Ciencia, Tecnología e Innovación 1 (1): 122-125. Blanchard, R. and H. Descimon (1988). "Hybridization between two species of swallowtails, meiosis mechanism, and the genesis of gynandromorphs." J. Lepid. Soc 42 : 94-102. Domínguez, L. and S. Bermúdez (2020). "Firsts records of abnormalities and gynandromorphism in hard ticks (Ixodida: Ixodidae) from Panama." Systematic and Applied Acarology 25 (7): 1199-1208. Graves, G. R., et al. (1996). "Comments on a Probable Gynandromorphic Black-Throated Blue Warbler." The Wilson Bulletin 108 (1): 178-180. Kumar, K. and S. Nagar (1979). "Two kinds of Gynandromorphs in ticks Boophilus microplus (Canestrini, 1888) and Hyalomma anatolicum Koch, 1844." Acarologia 20 (4): 518-521. Labruna, M. B., et al. (2002). "Gynandromorphism in Amblyomma cajennense and Rhipicephalus sanguineus (Acari: Ixodidae)." Journal of Parasitology 88 (4): 810-811. Loomis, E. and B. Stone (1970). "Gynandromorphs of Boophilus ticks (Acarina: Ixodidae)." Australian Journal of Entomology 9 (1): 68-70. Pereira, C. and M. Castro (1945). "Sobre un ginandromorfo de Rhipicephalus sanguineus Latr., 1804." Arquivos do Instituto Biológico 16 : 187-192. Prusinski, M., et al. (2015). "Two Gynandromorphs of Ixodes scapularis (Acari: Ixodidae) from New York State." Journal of Medical Entomology 52 (2): 278-282. Salceda-Sánchez, B., et al. (2020). "A case of gynandromorphism in Rhipicephalus sanguineus sl from Mexico." Experimental and Applied Acarology 82 (3): 405-409. Zhao, D., et al. (2010). "Somatic sex identity is cell autonomous in the chicken." Nature 464 (7286): 237-242. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 07 May, 2026 Reviews received at journal 17 Apr, 2026 Reviews received at journal 15 Apr, 2026 Reviewers agreed at journal 20 Mar, 2026 Reviewers agreed at journal 19 Mar, 2026 Reviewers invited by journal 19 Mar, 2026 Editor assigned by journal 17 Mar, 2026 Submission checks completed at journal 17 Mar, 2026 First submitted to journal 13 Mar, 2026 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. 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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-9115111","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":609895011,"identity":"62b5de4e-6568-452a-b137-b9801dd5cb3a","order_by":0,"name":"Marvin Stanley Rodriguez Aquino","email":"","orcid":"","institution":"University of El Salvador","correspondingAuthor":false,"prefix":"","firstName":"Marvin","middleName":"Stanley Rodriguez","lastName":"Aquino","suffix":""},{"id":609895013,"identity":"f03ac07f-1911-45fa-9b26-e909f1d72096","order_by":1,"name":"Esther Noemí Juárez Alvarado","email":"","orcid":"","institution":"University of El Salvador","correspondingAuthor":false,"prefix":"","firstName":"Esther","middleName":"Noemí Juárez","lastName":"Alvarado","suffix":""},{"id":609895014,"identity":"eb1256b0-14cc-4678-a117-6c84a8e9ea59","order_by":2,"name":"Francisco Javier Castaneda Lúe","email":"","orcid":"","institution":"University of El Salvador","correspondingAuthor":false,"prefix":"","firstName":"Francisco","middleName":"Javier Castaneda","lastName":"Lúe","suffix":""},{"id":609895015,"identity":"7de31bfb-88df-4294-ad00-4cf2353878f3","order_by":3,"name":"Pamela Michelle Cornejo Rivas","email":"","orcid":"","institution":"University of El Salvador","correspondingAuthor":false,"prefix":"","firstName":"Pamela","middleName":"Michelle Cornejo","lastName":"Rivas","suffix":""},{"id":609895017,"identity":"e0e5be44-8caa-4741-bf2a-6e768b6f095c","order_by":4,"name":"Melissa S. Nolan","email":"","orcid":"","institution":"University of South Carolina","correspondingAuthor":false,"prefix":"","firstName":"Melissa","middleName":"S.","lastName":"Nolan","suffix":""},{"id":609895018,"identity":"6322e94d-d18b-4896-b554-c87d98776b81","order_by":5,"name":"Lídia Gual-Gonzalez","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYBACPhDxgIFBjoEdLpaAXwsbVI0xAzOpWhIbiNfCv8bwQ8Ivm/T+ZuajG39U3GHgZ88xwK9F4o2xRGJfWu6Mw2xpt3nOPGOQ7HlDSMsZA4nEnsO5G5h5zG4zth1mMLhB0JYzxj+AWtINmPm/3fwJ1GJPUAt/j5lEwo/DCQbMPGw3eEG2SBC0ha3MIrEhzRDoFzOgXw7zSJx5VoBXCz//4c03Pvyxkedvb35280fFYTn+9uQNeLUwSCQwMDC2Ifg8+JWDrTkAJP4QVjcKRsEoGAUjGAAA4DVGsrhAZHoAAAAASUVORK5CYII=","orcid":"","institution":"Clemson University","correspondingAuthor":true,"prefix":"","firstName":"Lídia","middleName":"","lastName":"Gual-Gonzalez","suffix":""}],"badges":[],"createdAt":"2026-03-13 13:09:44","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9115111/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9115111/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105297577,"identity":"d0130d31-8013-4461-a59c-6cadd9d1121e","added_by":"auto","created_at":"2026-03-24 13:20:39","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":7725092,"visible":true,"origin":"","legend":"\u003cp\u003eMorphologic characteristics of gynandromorphic R. microplus. A) Dorsal view, B.-D) Ventral views. E) Lateral view. F) Capitulum. S=scutum, Gp=genital pore, Sp=spur, Ap=adanal plate, A=anal pore, Spp=spiracular plate, H=hypostome, P=palps\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9115111/v1/24f87c395fbb4aecee9e00ea.png"},{"id":105297652,"identity":"be58f8e9-9ae3-4a85-834a-2279257c275e","added_by":"auto","created_at":"2026-03-24 13:21:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":8007502,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9115111/v1/ea5c6f98-e8b2-4737-8978-14a3a4d59026.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"First report of gynandromorphism in Rhipicephalus microplus (Acari: Ixodidae) in El Salvador","fulltext":[{"header":"Introduction","content":"\u003cp\u003eGynandromorphism, also known as sexual chimerism, is a biological condition that can originate through diverse mechanisms, such as hormonal alterations (Graves, Patten et al. 1996), genetic anomalies during chromosomic separation (Zhao, McBride et al. 2010) or fecundation of binuclear oocytes as described by Blanchard \u0026amp; Descimon, 1988. When the male and female sexual characteristics distribution occurs in a comparable way in both hemi-bodies, the organism is classified as bilateral gynandromorph. If the alteration emerges during more advanced stages in the embryonic development or cellular division, the symmetry may be irregular or only partial, reaching more complex patterns expressed with axial configurations or mosaicism, which can evolve from different etiologic processes (Blanchard and Descimon 1988).\u003c/p\u003e\n\u003cp\u003eGynandromorphism is not an uncommon developmental abnormality in ticks. This phenomenon has been previously documented in some free-living genera of ticks, particularly \u003cem\u003eAmblyomma sp\u0026nbsp;\u003c/em\u003eand \u003cem\u003eHyalomma sp\u0026nbsp;\u003c/em\u003e(Prusinski, Mertins et al. 2015). In terms of gynandromorphism reports among the genus \u003cem\u003eRhipicephalus\u003c/em\u003e in Neotropical regions, there are some documented cases among brow dog tick, \u003cem\u003eRhipicephalus sanguineus\u003c/em\u003e sensu lato (Pereira and Castro 1945, Labruna, Ribeiro et al. 2002, Salceda-Sánchez, Sánchez-Montes et al. 2020). Similarly, there have been instances reported in \u003cem\u003eR. (Boophilus) microplus,\u0026nbsp;\u003c/em\u003ecorresponding to a category classified as semi-divided gynandromorphism called “ginandromorfismo semi-partido”, where both male and female characteristics are expressed as irregular features, mostly as presenting male parts on a female body (Kumar and Nagar 1979). This short communication describes the first reported instance of gynandromorphism in ticks in El Salvador in \u003cem\u003eR. microplus\u003c/em\u003e.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eStarting in 2021, the University of El Salvador’s Health Discovery and Investigation Center, (Centro de Investigación y Desarrollo en Salud), began a tick surveillance initiative aimed at detecting veterinary and medically important pathogens. In October 2025, colleagues were executing a systematic tick collection from cattle and the surrounding fields at the university’s agricultural research facility (Estación Experimental y de Prácticas, Facultad de Ciencias Agronómicas), in the municipality of San Luis Talpa, Departamento de La Paz (13°28'22.4\"N, 89°05'46.1\"W). During the sampling, an unusual specimen was found attached to a Holstein Brown Swiss cattle (\u003cem\u003eBos primigenius taurus\u003c/em\u003e), that was removed and preserved in a 70% ethanol and 5% glycerol-containing vial. Taxonomic identification was performed following the Garrapatas Ixodidae de Panamá key (Bermúdez, Apanaskevich et al. 2018). The specimen was examined and photographed using a stereomicroscope Leica EZ4E (Leica Microsystems Inc, Wetzlar, Germany).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe specimen collected was taxonomically identified as \u003cem\u003eR. microplus\u003c/em\u003e, with evidence of dorsally presenting gynandromorphism, with a bilateral asymmetric division. This transversal division goes from the base of the capitulum to the posterior end of the tick, presenting mostly female characteristics on the left side, and male characteristics on the right side (Figure 1A). The tick presents a scutum, characteristic of female ticks.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe ventral zone contains an anal groove slightly over the female side, whereas the genital pore is found medially located. It is worth noting that there is a tendency of these medial features to lean towards the male side due to the engorgement of the female side (Figure 1B). The male side shows adanal plates, often seen in male ticks; there is no caudal pedunculus (Figure 1D). On the male side, coxae present short, pointed spurs on the first coxa; comparatively, on the female side, these are short and rounded (Figure 1C). Spiracular plates can be observed on both sides (Figure 1E). The capitulum does not show division differences, unlike the idiosoma (Figure 1F). The basis capituli is small, hexagonal, anchored to the scutum, and presents shorter palps than the hypostome, characteristic of females.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eEvidence of gyandromorphism in \u003cem\u003eR. microplus\u0026nbsp;\u003c/em\u003e(previously, \u003cem\u003eBoophilus microplus\u003c/em\u003e) is limited to a few instances and has never reported in El Salvador. An earlier report from Loomis and Stone \u0026nbsp;found a \u003cem\u003eR. microplus\u003c/em\u003e collected from a Shorthorn calf with gynandromorphism in Australia(Loomis and Stone 1970). This individual showed female characteristics on the left side and male characteristics on the right side, although it did not have a complete bilateral division of both sexes, showing predominantly male characteristics. Similarly, our findings showed asymmetric distribution, with mostly predominant female characteristics. In contrast, a different gynandromorphic \u003cem\u003eR. microplus\u0026nbsp;\u003c/em\u003especimen was described in a collection from a Shri Bareilly Gowshala calf (Kumar and Nagar 1979). This Indian tick possessed a scutum in its normal location and a partial conscutum in a posterior lateral position to the left of the idiostoma. Although some of the features were male, the genital pore showed only female characteristics, while in our report the division between both sexes split the genital pore.\u003c/p\u003e\n\u003cp\u003eIn a recent review of a large tick collection from the Instituto Conmemorativo Gorgas de Estudios de la Salud in Panama, the team revised 6,624 hard ticks and identified 255 specimens with morphological anomalies. Their observations suggested that gynandromorphism and other general abnormalities are less frequent than local malformations; only two \u003cem\u003eAmblyomma dissimile\u003c/em\u003e specimens showed gynandromorphism(Domínguez and Bermúdez 2020). It has been suggested that gynandromorphism is more common in the genus \u003cem\u003eAmblyomma,\u0026nbsp;\u003c/em\u003ealthough this could be influenced by a general underreporting of morphological anomalies in ticks(Balinandi, Mugisha et al. 2019). While it seems to be found relevant for infectious agents(Domínguez and Bermúdez 2020), it does not seem to affect the tick’s ability to find a bloodmeal as evidenced by gynandromorph specimens collected from cattle.\u003c/p\u003e\n\u003cp\u003eWhile the relevance of this feature remains understudied, reporting these anomalies is important for the scientific community. Future research should continue focusing on the morphological diversity of medically and veterinary relevant arthropods in El Salvador, with the goal to better understand the biological impact and the possible ecological and epidemiological implications it carries.\u003c/p\u003e"},{"header":"References ","content":"\u003col\u003e\n \u003cli\u003eBalinandi, S., et al. (2019). \u0026quot;General and local morphological anomalies in Amblyomma lepidum (Acari: Ixodidae) and Rhipicephalus decoloratus infesting cattle in Uganda.\u0026quot; \u003cu\u003eJournal of Medical Entomology\u003c/u\u003e \u003cstrong\u003e56\u003c/strong\u003e(3): 873-877.\u003c/li\u003e\n \u003cli\u003eBerm\u0026uacute;dez, S., et al. (2018). \u0026quot;Garrapatas Ixodidae de Panam\u0026aacute;.\u0026quot; \u003cu\u003eSecretar\u0026iacute;a Nacional de Ciencia, Tecnolog\u0026iacute;a e Innovaci\u0026oacute;n\u003c/u\u003e \u003cstrong\u003e1\u003c/strong\u003e(1): 122-125.\u003c/li\u003e\n \u003cli\u003eBlanchard, R. and H. Descimon (1988). \u0026quot;Hybridization between two species of swallowtails, meiosis mechanism, and the genesis of gynandromorphs.\u0026quot; \u003cu\u003eJ. Lepid. Soc\u003c/u\u003e \u003cstrong\u003e42\u003c/strong\u003e: 94-102.\u003c/li\u003e\n \u003cli\u003eDom\u0026iacute;nguez, L. and S. Berm\u0026uacute;dez (2020). \u0026quot;Firsts records of abnormalities and gynandromorphism in hard ticks (Ixodida: Ixodidae) from Panama.\u0026quot; \u003cu\u003eSystematic and Applied Acarology\u003c/u\u003e \u003cstrong\u003e25\u003c/strong\u003e(7): 1199-1208.\u003c/li\u003e\n \u003cli\u003eGraves, G. R., et al. (1996). \u0026quot;Comments on a Probable Gynandromorphic Black-Throated Blue Warbler.\u0026quot; \u003cu\u003eThe Wilson Bulletin\u003c/u\u003e \u003cstrong\u003e108\u003c/strong\u003e(1): 178-180.\u003c/li\u003e\n \u003cli\u003eKumar, K. and S. Nagar (1979). \u0026quot;Two kinds of Gynandromorphs in ticks Boophilus microplus (Canestrini, 1888) and Hyalomma anatolicum Koch, 1844.\u0026quot; \u003cu\u003eAcarologia\u003c/u\u003e \u003cstrong\u003e20\u003c/strong\u003e(4): 518-521.\u003c/li\u003e\n \u003cli\u003eLabruna, M. B., et al. (2002). \u0026quot;Gynandromorphism in \u0026lt;span class=\u0026quot;genus-species\u0026quot;\u0026gt;Amblyomma cajennense\u0026lt;/span\u0026gt; and \u0026lt;span class=\u0026quot;genus-species\u0026quot;\u0026gt;Rhipicephalus sanguineus\u0026lt;/span\u0026gt; (Acari: Ixodidae).\u0026quot; \u003cu\u003eJournal of Parasitology\u003c/u\u003e \u003cstrong\u003e88\u003c/strong\u003e(4): 810-811.\u003c/li\u003e\n \u003cli\u003eLoomis, E. and B. Stone (1970). \u0026quot;Gynandromorphs of Boophilus ticks (Acarina: Ixodidae).\u0026quot; \u003cu\u003eAustralian Journal of Entomology\u003c/u\u003e \u003cstrong\u003e9\u003c/strong\u003e(1): 68-70.\u003c/li\u003e\n \u003cli\u003ePereira, C. and M. Castro (1945). \u0026quot;Sobre un ginandromorfo de \u003cem\u003eRhipicephalus sanguineus\u0026nbsp;\u003c/em\u003eLatr., 1804.\u0026quot; \u003cu\u003eArquivos do Instituto Biol\u0026oacute;gico\u003c/u\u003e \u003cstrong\u003e16\u003c/strong\u003e: 187-192.\u003c/li\u003e\n \u003cli\u003ePrusinski, M., et al. (2015). \u0026quot;Two Gynandromorphs of Ixodes scapularis (Acari: Ixodidae) from New York State.\u0026quot; \u003cu\u003eJournal of Medical Entomology\u003c/u\u003e \u003cstrong\u003e52\u003c/strong\u003e(2): 278-282.\u003c/li\u003e\n \u003cli\u003eSalceda-S\u0026aacute;nchez, B., et al. (2020). \u0026quot;A case of gynandromorphism in Rhipicephalus sanguineus sl from Mexico.\u0026quot; \u003cu\u003eExperimental and Applied Acarology\u003c/u\u003e \u003cstrong\u003e82\u003c/strong\u003e(3): 405-409.\u003c/li\u003e\n \u003cli\u003eZhao, D., et al. (2010). \u0026quot;Somatic sex identity is cell autonomous in the chicken.\u0026quot; \u003cu\u003eNature\u003c/u\u003e \u003cstrong\u003e464\u003c/strong\u003e(7286): 237-242.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"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":"Gynandromorphism, ticks, Rhipicephalus microplus","lastPublishedDoi":"10.21203/rs.3.rs-9115111/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9115111/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Gynandromorphism is a developmental anomaly characterized by the simultaneous presence of male and female morphological attributes within the same individual. This study documents the first case of gynandromorphism in the cattle tick Rhipicephalus microplus (Canestrini 1888) in El Salvador. The specimen was collected from a bovine belonging to the Experimental and Practical Station of the Faculty of Agronomic Sciences of the University of El Salvador, located in the municipality of San Luis Talpa, Department of La Paz. The reported gynandromorph of R. microplus exhibits bilateral symmetry, displaying primarily female characteristics on the left side and male characteristics on the right.","manuscriptTitle":"First report of gynandromorphism in Rhipicephalus microplus (Acari: Ixodidae) in El Salvador","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-24 13:20:34","doi":"10.21203/rs.3.rs-9115111/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-07T17:16:58+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-17T22:21:08+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-15T22:50:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"105922233263577635700363290640770811881","date":"2026-03-20T22:16:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"128363041016882789057190197763210862702","date":"2026-03-19T21:15:59+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-19T14:02:55+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-17T11:14:48+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-17T11:14:17+00:00","index":"","fulltext":""},{"type":"submitted","content":"Acta Parasitologica","date":"2026-03-13T13:02:49+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":"8014b342-d355-48ca-895e-edcbdc6ea404","owner":[],"postedDate":"March 24th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-07T17:16:58+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-19T03:38:11+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-24 13:20:34","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9115111","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9115111","identity":"rs-9115111","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}