Rhipicephalus sanguineus (Latreille, 1806) presents medical importance, being the principal vector of Rickettsia conorii, the causative agent of Botonous fever, occurring in various regions of Europe and Africa. In the Americas, has been reported as a vector of Rickettsia rickettsii, the causative agent of Mountain Spotted Fever. It presents veterinary importance because is responsible by the transmission of zoonosis like babesiosis, ehrlichiosis, hepatozoonosis and others. The resistance that these ticks show to some of the active principles used in acaricides has risen wildly. In other hand, the use of herbal medicines has been outstanding recently. Among the advantages of phytotherapics that justify their use are synergistic effects of its components and easy degradation in the environment. In this scenario, Tagetes patula L. (Asteraceae) appears as a species with great biocide potential. The phytochemical investigation of T. patula has resulted in the isolation of several chemical constituents such as benzofurans, carotenoids, flavonoids and thiophenes. This study aimed to test the effect of the ethanolic extract obtained from aerial parts of T. patula against eggs of R. sanguineus by Egg hatchability test and to verify, for the first time, the action of this sample on ovary cells of engorged females submitted to the Adult Immersion Test. The extract was very effective, inhibiting egg hatching in 96.98% (±0.025) with LD50=6.312mg/mL (4.064-8.497mg/mL). Microscopic analysis of the structure of the ovaries showed significant morphological changes in the structure of oocytes II-V and pedicel cells, interfering directly in its normal embryogenesis, impairing or impeding the formation of healthy larvae, breaking the life cycle of this ticks in the beginning. Despite the difficulty to control adult populations of ticks, these findings are important and provide an alternative to disrupt development on the environment.67 5561Abdel-Shafy, S., Zayed, A.A., In vitro acaricidal effect of plant extract of neem seed oil (Azadirachta indica) on egg, immature, and adult stages of Hyalomma anatolicum excavatum (Ixodoidea Ixodidae) (2002) Vet. Parasitol., 106, pp. 89-96Almeida, F.A.C., Goldfarb, A.C., Gouveia, J.P.G., Avaliação de extratos vegetais e métodos de aplicaçãono controle de Sitophilus spp (1999) Rev. Bras. Prod. Agroind., 1 (1), pp. 13-20Arnosti, A., Brienza, P.D., Furquim, K.C.S., Chierice, G.O., Neto, S.C., Bechara, G.H., Sampieri, B.R., Camargo-Mathias, M.I., Effects of Ricinus communis oil esters on salivary glands of Rhipicephalus sanguineus (Latreille, 1806) (Acari Ixodidae) (2011) Exp. Parasitol., 127, pp. 569-574Bano, H., Ahmed, S.W., Azhar, I., Ali, M.S., Alam, N., Chemical constituents of Tagetes patula L (2002) Pak. J. Pharm. Sci., 15 (2), pp. 1-12Barbosa, C.D.A.S., Borges, L.M., Nicácio, J., Alves, R.D., Miguita, C.H., Violante, I.M., Hamerski, L., Garcez, F.R., In vitro activities of plant extracts from the Brazilian Cerrado and Pantanal against Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) (2013) Exp. Appl. Acarol., 60 (3), pp. 421-430Bechara, G.H., Szabó, M.P.J., Ferreira, B.R., Garcia, M.V., Rhipicephalus sanguineus in Brazil: feeding and reproductive aspects under laboratorial conditions (1995) Rev. Bras. Parasitol. Vet., 4, pp. 61-66Broussalis, A.M., Ferraro, G.E., Martino, V.S., Pinzón, R., Coussio, J.D., Alvarez, J.C., Argentine plants as potential source of insecticidal compounds (1999) J. Ethnopharmacol., 67 (2), pp. 219-223Cestari, I.M., Sarti, S.J., Waib, C.M., Avaliação da atividade potencial inseticida de óleo essencial de Tagetes minuta (Asteraceae) contra Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae) (2004) Neotrop. Entomol., 33 (6), pp. 805-807Chopa, C.S., Descamps, L.R., Composition and biological activity of essential oils against Metopolophium dirhodum (Hemiptera: Aphididae) cereal crop pest (2012) Pest Manag. Sci., 68 (11), pp. 1492-1500Coutinho, M.T., Bueno, L.L., Sterzik, A., Fujiwara, R.T., Botelho, M., De, Maria, Genaro, O., Linardi, P.M., Participation of Rhipicephalus sanguineus (Acari: Ixodidae) in the epidemiology of canine visceral leishmaniasis (2005) Vet. Parasitol., 128 (1-2), pp. 149-155Dantas-Torres, F., The brown dog tick, Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae): from taxonomy to control (2008) Vet. Parasitol., 152 (3-4), pp. 173-185Dantas-Torres, F., Figueredo, L.A., Brandão-Filho, S.P., Rhipicephalus sanguineus (Acari: Ixodidae), the brown dog tick, parasitizing humans in Brazil (2006) Rev. Soc. Bras. Med. Trop., 39 (1), pp. 64-67Dantas-Torres, F., Figueredo, L.A., Faustino, M.A.G., Ectoparasitos de cães provenientes de alguns municípios da região metropolitana do Recife, Pernambuco, Brasil (2004) Rev. Bras. Parasitol. Vet., 13 (4), pp. 151-154Demma, L.J., Traeger, M.S., Nicholson, W.L., Paddock, C.D., Blau, D.M., Eremeeva, M.E., Dasch, G.A., Mcquiston, J.H., Rock Mountain spotted fever from an unexpected tick vector in Arizona (2005) New Eng. J. Med., 353, pp. 587-594Denardi, S.E., Bechara, G.H., Oliveira, P.R., Camargo-Mathias, M.I., Ultrastructural Analysis of the oocytes of female Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) ticks subjected to the action of Azadirachta indica A. Juss (Neem) (2012) Ultrastruct. Pathol., 36 (1), pp. 56-67Dharmaggada, V.S.S., Naik, S.N., Mittal, P.K., Vasudevan, P., Larvicidal activity of Tagetes patula essential oil against three mosquito species (2005) Bioresour. Technol., 96, pp. 1235-1240Elango, G., Abdu-Rahuman, A., Bagavan, A., Kamaraj, C., Abduz-Zahir, A., Rajakumar, G., Marimuthu, S., Santhoshkumar, T., Studies on effects of indigenous plant extracts on malarial vector, Anopheles subpictus Grassi (Diptera: Culicidae) (2010) Trop. Biomed., 27 (2), pp. 143-154Elango, G., Zahir, A.A., Bagavan, A., Kamaraj, C., Rajakumar, G., Santhoshkumar, T., Marimuthu, S., Rahuman, A.A., Efficacy of indigenous plant extracts on the malaria vector Anopheles subpictus Grassi (Diptera: Culicidae) (2011) Indian J. Med. Res., 134, pp. 375-383Elango, G., Rahuman, A.A., Evaluation of medicinal plant extracts against ticks and fluke (2011) Parasitol. Res., 108 (3), pp. 513-519Faizi, S., Fayyaz, S., Bano, S., Igbal, E.Y., Lubna Siddigi, H., Naz, H., Isolation of nematicidal compounds from Tagetes patula L. yellow flowers: structure-activity relationship studies against cyst nematode Heterodera zeae infective stage larvae (2011) J. Agric. Food Chem., 59 (17), pp. 9080-9093Furlong, J., Booohilus microplus, o carrapato dos bovinos (2000) Juiz de Fora: EMBRAPA Gado de Leite, pp. 17-33. , Área de Comunicação Empresarial, Práticas de Manejo Sanitário em Bovinos de Leite (Ed.)Garcia, M.V., Matias, J., Barros, J.C., De Lima, D.P., Lopes, R.S., Andreotti, R., Chemical identification of Tagetes minuta Linnaeus (Asteraceae) essential oil and its acaricidal effect on ticks (2012) Rev. Bras. Parasitol. Vet., 21 (4), pp. 405-411Green, M.M., Singer, J.M., Sutherland, D.J., Hibben, C.R., Larvicidal activity of Tagetes minuta (marigold) toward Aedes aegypti (1991) J. Am. Mosq. Control Assoc., 7 (2), pp. 282-286Guimarães, J.H., Tucci, E.C., Barros-Battesti, D.M., (2001) Ectoparasitos de importância veterinária, p. 213. , Editora Plêidade, São PauloHadjiakhoondi, A., Vatandoost, H., Khanavi, M., Abai, M.R., Biochemical investigation of different extracts and larvicidal activity of Tagetes minuta L on Anopheles stephensi larvae (2005) Iran. J. Pharm. Sci., 1, pp. 81-84Hinton, H.E., (1981) Biology of Insect Eggs, , Pergamon Press, OxfordIreri, L.N., Kongoro, J., Ngure, P., Mutai, C., Langat, B., Tonui, W., Kimutai, A., Mucheru, O., The potential of the extracts of Tagetes minuta Linnaeus (Asteraceae), Acalypha fruticosa Forssk (Euphorbiaceae) and Tarchonanthus camphoratus L. (Compositae) against Phlebotomus duboscqi Neveu Lemaire (Diptera: Psychodidae), the vector for Leishmania major Yakimoff and Schokhor (2010) J. Vector Borne Dis., 47 (3), pp. 168-174Jaskoski, B.J., Butler, V., Rhipicephalus sanguineus: amino acid composition of egg shell (1971) Exp. Parasitol., 30, pp. 400-406Jernigan, A.D., Mctier, T.L., Chieffo, C., Thomas, C.A., Krautmann, M.J., Hair, J.A., Young, D.R., Rowan, T.G., Efficacy of selamectin against experimentally induced tick (Rhipicephalus sanguineus and Dermacentor variabilis) infestations on dogs (2000) Vet. Parasitol., 91, pp. 359-375Kaaya, G.P., Mwangi, E.N., Malonza, M.M., Acaricidal activity of Margaritaria discoidea (Euphorbiaceae) plant extract against the ticks Rhipicephalus appendiculatus and Amblyomma variegatum (Ixodidae) (1995) Int. J. Acarol., 21 (2), pp. 123-129Kyarimpa, C.M., Bohmdorfer, S., Wasswa, J., Kiremire, B.T., Ndiege, I.O., Kabasa, J.D., Essential oil and composition of Tagetes minuta from Uganda. Larvicidal activity on Anopheles gambiae (2014) Ind. Crop Prod., 62, pp. 400-404King, P.E., The rate of egg resorption in Nasonia vitripennis deprived of hosts (1963) Proc. R. Entomol. Soc. London, 38, pp. 98-100Koch, H.G., Tuck, M.D., Molting and survival of the brown dog tick (Acari: Ixodidae) under different temperatures and humidities (1986) Ann. Entomol. Soc. Am., 79 (1), pp. 11-14Kongkiatpaiboon, S., Pattarajinda, V., Keeratinijakal, V., Gritsanapan, W., Effect of Stemona spp. against Rhipicephalus microplus (2014) Exp. Appl. Acarol., 62 (1), pp. 115-120Krishna, A., Prajapati, V., Bhasney, S., Tripathi, A.K., Potential toxicityof new genotypes of Tagetes (Asteraceae) species against stored grain insect pests (2005) Int. J. Trop. Insect Sci., 25, pp. 122-128Lees, A.D., Beament, J.W., An egg-waxing organ in ticks (1948) Q. J. Microsc. Sci., 89 (3), pp. 291-322Lima, B., López, S., Luna, L., Agüero, M.B., Aragón, L., Tapia, A., Zacchino, S., Feresin, G.E., Essential oils of medicinal plants from the central andes of Argentina: chemical composition, and antifungal, antibacterial, and insect-repellent activities (2011) Chem. Biodivers., 8 (5), pp. 924-936López, S.B., López, M.L., Aragón, L.M., Tereschuk, M.L., Slanis, A.C., Feresin, G.E., Zygadlo, J.A., Tapia, A.A., Composition and anti-insect activity of essential oils from Tagetes L. species (Asteraceae, Helenieae) on Ceratitis capitata Wiedemann and Triatoma infestans Klug (2011) J. Agric. Food Chem., 59 (10), pp. 5286-5292Macêdo, M.E., Consoli, R.A.G.B., Grandi, S.M.T., Anjos, A.M.G., Oliveira, A.B., Mendes, N.M., Queiroz, R.O., Zani, C.L., Screening of Asteraceae (Compositae) plant extracts for larvicidal activity against Aedes fluviatilis (Diptera: Culicidae) (1997) Mem. Inst. Oswaldo Cruz, 92, pp. 565-570Marques, M.M., Morais, S.M., Vieira, I.G., Vieira, M.G., Raquel, A., Silva, A., De Almeida, R.R., Guedes, M.I., Larvicidal activity of Tagetes erecta against Aedes aegypti (2011) J. Am. Mosq. Control Assoc., 27 (2), pp. 156-158Massard, C.L., Fonseca, A.H., Carrapatos e doenças transmitidas, comuns ao homem e aos animais (2004) A Hora Vet., 135, pp. 15-23Massera, P.E., Rodriguez, T., Giulietti, A.M., Thiophene production in transformed roots cultures of Tagetes filifolia (1998) Biotechnol. Lett., 20 (6), pp. 573-577Merle, C., Sotto, A., Barbuat, C., Jourdan, J., Disease course of Mediterranean Spotted Fever: remark on 16 cases (1998) Méd. Malad. Infect., 28 (5), pp. 400-401Miller, R.J., George, J.E., Guerrero, F., Carpenter, L., Welch, J.B., Characterization of acaricide resistance in Rhipicephalus sanguineus (Latreille) (Acari: Ixodidae) collected from the Corozal Army Veterinary Quarantine Center, Panama (2001) J. Med. Entomol., 38, pp. 298-302Nchu, F., Magano, S.R., Eloff, J.N., In vitro anti-tick properties of the essential oil of Tagetes minuta L. (Asteraceae) on Hyalomma rufipes (Acari: Ixodidae) (2012) Onderstepoort J. Vet. Res., 79 (1), pp. E1-E5Oliveira, P.R., Bechara, G.H., Denardi, S.E., Saito, K.C., Nunes, E.T., Szabó, M.P.J., Camargo-Mathias, M.I., Comparison of the external morphology of Rhipicephalus sanguineus (Latreille, 1806) (Acari Ixodidae) ticks from Brazil and Argentina (2005) Vet. Parasitol., 129, pp. 139-147Otranto, D., Lia, R.P., Cantacessi, C., Galli, G., Paradies, P., Mallia, E., Capelli, G., Efficacy of a combination of imidacloprid 10%/permethrin 50% versus fipronil 10%/(S)-methoprene 12% against ticks in naturally infected dogs (2005) Vet. Parasitol., 130, pp. 293-304Paião, J.C.V., Monteiro, A.C., Kronka, S., Susceptibility of the cattle tick Boophilus microplus (Acari: Ixodidae) to isolates of the fungus Beauveria bassiana (2001) World J. Microbiol. Biotechnol., 17 (3), pp. 245-251Pazinato, R., Klauck, V., Volpato, A., Tonin, A.A., Santos, R.C., De Souza, M.E., Vaucher, R.A., Da Silva, A.S., Influence of tea tree oil (Melaleuca alternifolia) on the cattle tick Rhipicephalus microplus (2014) Exp. Appl. Acarol., 63 (1), pp. 77-83Pegram, R.G., Keirans, J.E., Clifford, C.M., Walker, J.B., Clarification of the Rhipicephalus sanguineus group (Acari Ixodoidea, Ixodidae). II. R. sanguineus (Latreille, 1806) and related species (1987) Syst. Parasitol., 10, pp. 27-44Perich, M., Wells, C., Bertsch, W., Tredway, K., Isolation of the insecticidal components of Tagetes minuta (Compositae) against mosquito larvae and adults (1995) J. Am. Mosq. Control Assoc., 11, pp. 307-310Politi, F.A.S., Figueira, G.M.F., Araújo, A.M., Sampieri, B.R., Camargo-Mathias, M.I., Szabó, M.P.J., Bechara, G.H., Pietro, R.C.L.R., Acaricidal activity of ethanolic extract from aerial parts of Tagetes patula L. (Asteraceae) against larvae and engorged adult females of Rhipicephalus sanguineus (Latreille 1806) (2012) Paras. Vect., 5, pp. 295-306Politi, F.A.S., Moreira, T.M.S., Rodrigues, E.R., Queiroz, G.M., Figueira, G.M., Januário, A.H., Berenger, J.M., Pietro, R.C.L.R., Chemical characterization and acaricide potential of essential oil from aerial parts of Tagetes patula L. (Asteraceae) against engorged adult females of Rhipicephalus sanguineus (Latreille, 1806) (2013) Parasitol. Res., 112 (6), pp. 2261-2268Ravindran, R., Juliet, S., Sunil, A.R., Ajith-Kumar, K.G., Nair, S.N., Amithamol, K.K., Bandyopadhyay, A., Ghosh, S., Acaricidal activity of Cassia alata against Rhipicephalus (Boophilus) annulatus (2012) Exp. Appl. Acarol., 56 (1), pp. 69-74Restello, R.M., Menegatt, C., Mossi, A.J., Effect of the essential oil of Tagetes patula L. (Asteraceae) on Sitophilus zeamais Motschulsky (Coleoptera, Curculionidae) (2009) Rev. Bras. Entomol., 53 (2), pp. 304-307Ribeiro, V.L.S., Avancini, C., Gonçalves, K., Toigo, E., Von-Poser, G., Acaricidal activity of Calea serrata (Asteraceae) on Boophilus microplus and Rhipicephalus sanguineus (2008) Vet. Parasitol., 151, pp. 351-354Sabatini, G.A., Kemp, D.H., Hughes, S., Nari, A., Hansen, J., Tests to determine LC50 and discriminating doses for macrocyclic lactones against the cattle tick Boophilus microplus (2001) Vet. Parasitol., 95, pp. 53-62Sampieri, B.R., Arnosti, A., Nunes, P.H., Furquim, K.C.S., Chierice, G.O., Camargo-Mathias, M.I., Ultrastructural changes in the ovary cells of engorged Rhipicephalus sanguineus female ticks treated with esters of ricinoleic acid from castor oil (Ricinus communis) (2012) Microsc. Res. Tech., 75, pp. 683-690Singh, N.K., Jyoti Vemu, B., Nandi, A., Singh, H., Kumar, R., Dumka, V.K., Laboratory assessment of acaricidal activity of Cymbopogon winterianus, Vitex negundo and Withania somnifera extracts against deltamethrin resistant Hyalomma anatolicum (2014) Exp. Appl. Acarol., 63 (3), pp. 423-430Vatsya, S., Yadav, C.L., Evaluation of acaricide resistance mechanisms in field populations of Rhipicephalus (Boophilus) microplus collected from India (2011) Int. J. Acarol., 37 (5), pp. 405-410Woldehiwet, Z., Ristic, M., (1993) Rickettsial and Chlamydial Diseases of Domestic Animals, p. 427. , Pergamon, Oxford(2006) Pesticides and their Application for the Control of Vectors and Pests of Public Health Importance, p. 114. , GenevaYoshinari, N.H., Barros, P.J.L., Bonoldi, V.L.N., Ishikawa, M., Battesti, D.M.B., Pirana, S., Fonseca, A.H., Schumaker, T.T., Perfil da borreliose de lyme no Brasil (1997) Rev. Hosp. Clin., 52, pp. 111-117Yunes, R.A., Pedrosa, R.C., Cechinel-Filho, V., Fármacos e fitoterápicos: a necessidade do desenvolvimento da indústria de fitoterápicos no Brasil (2001) Quím. Nova, 24 (1), pp. 147-152