Updated checklist of the mosquitoes (Diptera: Culicidae) of Mexico.

Based on historical and recent records, an updated list of 244 nominal species and three undescribed mosquitoes from Mexico is presented. Since 1990, 15 species have been recorded for the first time in Mexico: Aedes guatemala, Ae. brelandi, Ae. insolitus, Ae. melanimon, Ae. albopictus, Culex daumastocampa, Cx. metempsytus, Cx. erethyzonfer, Culiseta melanura, Limatus asulleptus, Sabethes gymnothorax, Trichoprosopon pallidiventer, Toxorhynchites moctezuma, Uranotaenia socialis, and Wyeomyia chalcocephala. Five species were discovered and described: Ae. amaterui, Ae. lewnielseni, Cx. diamphidius, Shannoniana huasteca, and Tr. mixtli. Three species were discovered without yet describing or naming them: Ae. (Protomacleaya) sp. 1, Ae. (Ochlerotatus) sp. 2, and Wyeomyia sp. 3. Five species had been removed from the Mexican mosquito fauna: Ae. stigmaticus, Cx. imitator, Onirion personatum, Sa. tarsopus, and Tx. theobaldi. With the intention of updating the checklist of the mosquito species in Mexico, historical and recent species records were reviewed, as well as the review of entomological collections, resulting in the confirmation of the presence in Mexico of Ae. thelcter, Cs. impatiens, and Orthopodomyia alba. Morphological and molecular evidence confirms the presence of Wy. jocosa, while Anopheles atropos, Psorophora confinnis, Cx. jenningsi, Mansonia indubitans, Tr. pallidiventer, and Tr. soaresi are removed from the Mexican mosquito fauna.

The Distribution of Uranotaenia sapphirina and Ur. socialis in Tabasco, Southern Mexico.

In Mexico, the genus Uranotaenia includes 11 species distributed mainly in the tropical and subtropical regions in the southeast of the country. Uranotaenia sapphirina has been reported in 18 states in Mexico: Campeche, Coahuila, Colima, Chiapas, Guerrero, Hidalgo, Jalisco, Mexico City, Mexico State, Michoacán, Morelos, Oaxaca, Quintana Roo, Sinaloa, Tabasco, Tamaulipas, Veracruz, and Yucatán; whereas Ur. socialis has been reported in Chiapas and Quintana Roo. In recent surveillance studies of mosquito species in Tabasco, Ur. sapphirina and Ur. socialis were omitted due to the lack of recent collection records, but in historical records, the presence of Ur. sapphirina and one species consistent with the description of Ur. socialis were mentioned. During a mosquito survey collection, immature stages from ground-level natural habitats in conservation areas of Tabasco, Ur. sapphirina and Ur. socialis were collected in association with Anopheles albimanus, Culex erraticus, Mansonia titillans, and Ur. lowii. Additionally, 2 Mexican entomological collections were reviewed, searching additional records of those species. An identification key to separate larvae and adult females of Ur. sapphirina and Ur. socialis is provided. With the addition of Ur. sapphirina and Ur. socialis to the mosquito fauna of Tabasco, there are currently 107 species in the state, being the 3rd state in Mexico with the highest richness of mosquito species. Specimens collected during this study were deposited in the Collection of the Entomological and Bioassay Research Unit of Tabasco.

First Record of Wyeomyia mitchellii in Nuevo León, Mexico.

On October 5, 2021, mosquito collections were conducted in Nuevo León in search of an undescribed species within the genus Wyeomyia reported previously in this state. Species collected included Aedes quadrivittatus, Ae. amabilis, Ae. triseriatus group, Ae. albopictus, and Wy. mitchellii. Although the undescribed species was not found, the occurrence record for Wy. mitchellii in Nuevo León constitutes the 1st record for this species in this state. Additionally, historical records of the presence of Wy. mitchelli in Mexico, available in the literature, were reviewed and updated. Specimens collected during this study were deposited in the Culicidae Collection of the Parasitology Department, Autonomous Agrarian University Antonio Narro, Laguna unit. With the addition of Wy. mitchellii to the mosquito fauna of Nuevo León, there are currently 67 species in the state.

First national record of Aedes melanimon (Diptera: Culicidae) in Mexico.

Aedes (Ochlerotatus) melanimon Dyar 1924 has been considered an important pest in agricultural and rural communities. Aedes melanimon is a vector of WEEV and CEV and is a competent laboratory vector of WNV. The known range of Ae. melanimon extends throughout Southwest Canada, part of Central and most of Western USA. Here we report the first record of Ae. melanimon in Mexico, at Ciudad Juárez, Chihuahua. The collect represents the southernmost distributional record for this species. Its indigenous presence in a highly urbanized and dry area was not expected. A permanent surveillance program to detect and determine the species in border-crossing cities is encouraged.

Integrated Approaches for the Identification of Mosquitoes (Diptera: Culicidae) from the Volcanoes of Central America Physiographic Subprovince of the State of Chiapas, Mexico.

Nowadays, there is a lack of information on the mosquito's fauna and DNA barcoding sequence reference library from many areas in Mexico, including the Volcanoes of Central America physiographic subprovince in the state of Chiapas. Consequently, a survey was undertaken to delineate the mosquito (Diptera: Culicidae) fauna in this region across different seasons using different collecting techniques. All species were identified by morphology and DNA barcoding, and their ecological features were also defined. In total, 62 taxa were morphologically examined, 60 of these were successfully identified based on morphological characteristics, but two were unable to be identified at the species level. The genera Aedes, Anopheles, Culex, and Wyeomyia are the most diverse among mosquito genera collected and include several species of medical and veterinary importance. Ecological characteristics of the immature habitats indicated that they were grouped into four categories namely, (1) large water bodies at ground level, (2) small and shady phytotelmata (e.g., tree holes and bamboo internodes), (3) large phytotelmata (e.g., plant leaves and axis bromeliad), and (4) artificial containers. The cytochrome c oxidase subunit I (COI) DNA barcoding sequences successfully separated the majority of these species, although specific species showed >2% intraspecific genetic divergences.

DNA Barcoding of Mosquitoes from the Pantanos de Centla Biosphere Reserve, Southeastern Mexico.

Accurate identification of mosquito species is essential to support programs that involve the study of distribution and mosquito control. Numerous mosquito species are difficult to identify based only on morphological characteristics, due to the morphological similarities in different life stages and large numbers of some species that are members of morphologically similar species complexes. In the present study, the mosquitoes collected in the Pantanos de Centla Biosphere Reserve, southeastern Mexico, were evaluated using a combination of morphological and molecular approaches (mitochondrial cytochrome c oxidase subunit I [COI] DNA barcode). A total of 1,576 specimens of 10 genera and 35 species, mostly adult stages, were collected. A total of 225 COI DNA barcode sequences were analyzed; most species formed well-supported groups in the neighbor joining, maximum likelihood, and Bayesian inference trees. The intraspecific Kimura 2-parameter (K2P) genetic distance averaged 1.52%. An intraspecific K2P distance of 6.20% was observed in Anopheles crucians s.l., while a deep split was identified in Culex erraticus and Cx. conspirator. This study showed that COI DNA barcodes offer a reliable approach to support mosquito species identification in Mexico.

First National Record for Culex iridescens in Peru.

On October 9, 2019, mosquito collections were conducted to update the mosquito species of medical importance in the Apurímac River Valley, Canayre, in the state of Ayacucho, Peru. Species collected included Culex (Carrollia) iridescens, which had been previously reported only in Colombia, Ecuador, and Brazil, this being the first national report of this species in Peru and the first species within the genus Culex in Ayacucho. With the addition of Cx. iridescens to the mosquito fauna of Peru, there are currently 182 species in the country. Specimens collected during this study were deposited in the Entomological Collection of the Natural History Museum of the National University of San Cristobal Huamanga in Ayacucho, Peru.

First Record of Aedes podographicus in Nuevo León State, Mexico.

In Mexico, Aedes podographicus is one of the most common species within the subgenus Protomacleaya of Aedes. This species has been collected in 12 states close to the coastal regions; however, few records confirm the presence of Ae. podographicus inland. During a mosquito-survey using ovitraps in the state of Nuevo León, Mexico, Ae. podographicus was collected in association with Ae. albopictus and Culex quinquefasciatus. This is the first record of the presence of Ae. podographicus in Nuevo León. With the addition of Ae. podographicus to the mosquito fauna of Nuevo León, there are currently 66 species in the state, 19 within the genus Aedes and 6 within the subgenus Protomacleaya, the genus Aedes being the group with the major number of species in Nuevo León. Specimens collected during this study were deposited in the collection of insects and mites of medical importance of the Laboratory of Medical Entomology of the Autonomous University of Nuevo León, Mexico.

Identification of mosquitoes (Diptera: Culicidae) from Mexico State, Mexico using morphology and COI DNA barcoding.

Mosquitoes are commonly identified to species level using morphological traits, but complementary methods for identification are often necessary when specimens are collected as immature stages, stored inadequately, or when delineation of species complexes is problematic. DNA-barcoding using the mitochondrial cytochrome c oxidase subunit 1 (COI) gene is one such tool used for the morphological identification of species. A comprehensive entomological survey of mosquito species in Mexico State identified by COI DNA barcoding and morphology is documented in this paper. Specimens were collected from all the physiographic provinces in Mexico State between 2017 and 2019. Overall, 2,218 specimens were collected from 157 localities representing both subfamilies Anophelinae and Culicinae. A species checklist that consists of 6 tribes, 10 genera, 20 subgenera, and 51 species, 35 of which are new records for Mexico State, is provided. Three hundred and forty-two COI sequences of 46 species were analysed. Mean intraspecific and interspecific distances ranged between 0% to 3.9% and from 1.2% to 25.3%, respectively. All species groups were supported by high bootstraps values in a Neighbour-Joining analysis, and new COI sequences were generated for eight species: Aedes chionotum Zavortink, Ae. vargasi Schick, Ae. gabriel Schick, Ae. guerrero Berlin, Ae. ramirezi Vargas and Downs, Haemagogus mesodentatus Komp and Kumm, Culex restrictor Dyar and Knab, and Uranotaenia geometrica Theobald. This study provides a detailed inventory of the Culicidae from Mexico State and discusses the utility of DNA barcoding as a complementary tool for accurate mosquito species identification in Mexico.

Diversity and potential distribution of culicids of medical importance of the Yucatan Peninsula, Mexico / Diversidad y distribución potencial de culícidos de importancia médica de la Península de Yucatán, México

Abstract: Objective: To determine the species distribution, abundance, and diversity of culicids in the Yucatan Peninsula (YP); their potential distribution, using ecological niche modeling (ENM), and the risk of contact with urban and rural populations. Materials and methods: A cross-sectional study was carried out through the YP. The diversity of species was determined with the Shannon index. The potential distribution of the culicids was determined through the ENM, as well as the risk of urban and rural populations through contact with vectors. Results: A total of 10 699 specimens, 15 genera and 52 species were registered. Campeche and the Biosphere Reserve of Calakmul exhibited the highest diversity. Conclusions: The ENM predict a high suitability in all the YP of Ae. aegypti, An. albimanus, An. pseudopuntipennis, Cx. coronator, and Cx. quinquefasciatus. The vector species that exhibited the highest risk of contact in the YP were Cx. quinquefasciatus, Ae. aegypti and Ae. albopictus.

Resumen: Objetivo: Determinar la distribución, abundancia y di versidad de los culícidos de la Península de Yucatán (PY), su distribución potencial utilizando modelos de nicho ecológico (MNE) y el riesgo de contacto con poblaciones urbanas y rurales. Material y métodos: Se realizó un estudio transversal. La diversidad fue determinada por el índice de Shannon. La distribución potencial de los culícidos se deter minó a través de MNE, así como el riesgo de las poblaciones urbanas y rurales al contacto con los vectores. Resultados: En total, se registraron 10 699 especímenes, 15 géneros y 52 especies. Campeche y la Reserva de la Biosfera de Calakmul presentaron la mayor diversidad. Conclusiones: El MNE predice una alta idoneidad en toda la PY para Ae. aegypti, An. albimanus, An. pseudopuntipennis, Cx. coronador y Cx. quinque fasciatus. Las especies de vectores que presentaron el mayor riesgo de contacto en la PY fueron Cx. quinquefasciatus, Ae. aegypti y Ae. albopictus.

Diversity and potential distribution of culicids of medical importance of the Yucatan Peninsula, Mexico.

OBJECTIVE: To determine the species distribution, abundance, and diversity of culicids in the Yucatan Peninsula (YP); their potential distribution, using ecological niche modeling (ENM), and the risk of contact with urban and rural populations. MATERIALS AND METHODS: A cross-sectional study was carried out through the YP. The diversity of species was determined with the Shannon index. The potential distribution of the culicids was determined through the ENM, as well as the risk of urban and rural populations through contact with vectors. RESULTS: A total of 10 699 specimens, 15 genera and 52 species were registered. Campeche and the Biosphere Reserve of Calakmul exhibited the highest diversity. CONCLUSIONS: The ENM predict a high suitability in all the YP of Ae. aegypti, An. albimanus, An. pseudopuntipennis, Cx. coronator, and Cx. quinquefasciatus. The vector species that exhibited the highest risk of contact in the YP were Cx. quinquefasciatus, Ae. aegypti and Ae. albopictus.

OBJETIVO: Determinar la distribución, abundancia y diversidad de los culícidos de la Península de Yucatán (PY), su distribución potencial utilizando modelos de nicho ecológico (MNE) y el riesgo de contacto con poblaciones urbanas y rurales. MATERIAL Y MÉTODOS: Se realizó un estudio transversal. La diversidad fue determinada por el índice de Shannon. La distribución potencial de los culícidos se determinó a través de MNE, así como el riesgo de las poblaciones urbanas y rurales al contacto con los vectores. RESULTADOS: En total, se registraron 10 699 especímenes, 15 géneros y 52 especies. Campeche y la Reserva de la Biosfera de Calakmul presentaron la mayor diversidad. CONCLUSIONES: El MNE predice una alta idoneidad en toda la PY para Ae. aegypti, An. albimanus, An. pseudopuntipennis, Cx. coronador y Cx. quinquefasciatus. Las especies de vectores que presentaron el mayor riesgo de contacto en la PY fueron Cx. quinquefasciatus, Ae. aegypti y Ae. albopictus.

An Integrated Molecular Approach to Untangling Host-Vector-Pathogen Interactions in Mosquitoes (Diptera: Culicidae) From Sylvan Communities in Mexico.

There are ~240 species of Culicidae in Mexico, of which some are vectors of arthropod-borne viruses such as Zika virus, dengue virus, chikungunya virus, and West Nile virus. Thus, the identification of mosquito feeding preferences is paramount to understanding of vector-host-pathogen interactions that, in turn, can aid the control of disease outbreaks. Typically, DNA and RNA are extracted separately for animal (insects and blood meal hosts) and viral identification, but this study demonstrates that multiple organisms can be analyzed from a single RNA extract. For the first time, residual DNA present in standard RNA extracts was analyzed by DNA barcoding in concert with Sanger and next-generation sequencing (NGS) to identify both the mosquito species and the source of their meals in blood-fed females caught in seven sylvan communities in Chiapas State, Mexico. While mosquito molecular identification involved standard barcoding methods, the sensitivity of blood meal identification was maximized by employing short primers with NGS. In total, we collected 1,634 specimens belonging to 14 genera, 25 subgenera, and 61 morphospecies of mosquitoes. Of these, four species were new records for Mexico (Aedes guatemala, Ae. insolitus, Limatus asulleptus, Trichoprosopon pallidiventer), and nine were new records for Chiapas State. DNA barcode sequences for >300 bp of the COI gene were obtained from 291 specimens, whereas 130 bp sequences were recovered from another 179 specimens. High intraspecific divergence values (>2%) suggesting cryptic species complexes were observed in nine taxa: Anopheles eiseni (5.39%), An. pseudopunctipennis (2.79%), Ae. podographicus (4.05%), Culex eastor (4.88%), Cx. erraticus (2.28%), Toxorhynchites haemorrhoidalis (4.30%), Tr. pallidiventer (4.95%), Wyeomyia adelpha/Wy. guatemala (7.30%), and Wy. pseudopecten (4.04%). The study increased the number of mosquito species known from 128 species to 138 species for Chiapas State, and 239 for Mexico as a whole. Blood meal analysis showed that Aedes angustivittatus fed on ducks and chicken, whereas Psorophora albipes fed on humans. Culex quinquefasciatus fed on diverse hosts including chicken, human, turkey, and Mexican grackle. No arbovirus RNA was detected by reverse transcriptase-polymerase chain reaction in the surveyed specimens. This study demonstrated, for the first time, that residual DNA present in RNA blood meal extracts can be used to identify host vectors, highlighting the important role of molecular approaches in both vector identification and revealing host-vector-pathogen interactions.

New Records and Updated Checklist of Mosquito Species in Quintana Roo, Mexico, Using DNA-Barcoding.

Collections of mosquitoes were conducted as part of the entomological vector surveillance in Quintana Roo State, Mexico, during September 2015. Species collected included Anopheles gabaldoni, An. darlingi, Psorophora columbiae, Culex inflictus, Cx. trifidus, Cx. lactator, and Wyeomyia guatemala s.l. All the specimens were identified by morphological and molecular characters (DNA-barcoding). This is the 1st time these species are reported in the Mexican state of Quintana Roo. This research updates and increases the list of species of mosquitoes in Quintana Roo from 79 to 86.

Comparison of two DNA extraction methods from larvae, pupae, and adults of Aedes aegypti.

Mosquitoes are the most important arthropods from the point of view of public health, due to the fact that they can transmit a large number of pathogens which can cause diseases to humans and animals. Aedes aegypti (L.) is one of the most important vector species in the world, since it can transmit numerous pathogens such as dengue, Zika, and chikungunya. Therefore, studies involving the molecular aspects of this and other mosquitoes species are currently increasing. In this report, we describe the comparison between two DNA extraction techniques, Chelex and cetyltrimethylammonium bromide (CTAB), for carrying out DNA extraction in larvae, pupae and adult female of Ae. aegypti. The Chelex technique was superior in the amount and purity of DNA as compared to the CTAB technique in the three life stages we tested.

First Record of Psorophora ferox In Durango State, Mexico.

During August-November of 2018, mosquito collections were conducted with the intention of monitoring the presence of arboviruses in Durango State, Mexico. Species collected included Psorophora (Janthinosoma) ferox. In Mexico, 24 species of the genus Psorophora have been previously reported, whereas in the state of Durango, only 2 species have been reported: Psorophora (Grabhamia) columbiae and Ps. (Gra.) signipennis. This is the 1st record of Ps. ferox and the subgenus Janthinosoma in Durango. With the addition of Ps. ferox to the list of mosquito species found in Durango, the number of mosquito species occurring in the state stands at 31.

The mosquitoes (Diptera: Culicidae) of Nuevo León, Mexico, with descriptions of two new species.

To document the diversity and distribution of mosquitoes inhabiting the Mexican state of Nuevo León, collection trips were conducted to all physiographic regions (Grand Northamerican Plains, Coastal Plain of North Gulf, and Sierra Madre Oriental) and subregions across the state. A total of 3,176 specimens were collected. Additionally, we re-examined mosquito specimens in two Mexican entomological collections: The Collection of Insects and Mites of Medical Importance and the Collection of Arthropods of Medical Importance. These represent the two culicid subfamilies Anophelinae and Culicinae, 8 tribes, 12 genera, 25 subgenera, and 64 named species. Of these, 1 tribe, 2 genera, 5 subgenera, and 14 species are new records for the mosquito fauna of Nuevo León. Three undescribed species were collected. Two are described in this study: Aedes (Ochlerotatus) amateuri Ortega & Zavortink n. sp., and Aedes (Protomacleaya) lewnielseni Ortega & Zavortink n. sp. The third belongs to the genus Wyeomyia. Twelve species previously recorded from Nuevo León were not collected during this study. Taxonomic notes, new distribution limits, and comments about the medical importance of some species are reported.

First Record of Aedes gabriel in Hidalgo State, Mexico.

Aedesgabriel is one of the rare species endemic in Mexico. This species was originally described from specimens collected in the state of Morelos in 1970; however, very few occurrence records have been published since. During an ovitrap survey of mosquitoes in 2018, eggs of Ae. gabriel were collected for the 1st time in the state of Hidalgo, Mexico. Aedes gabriel appears to have become common and the species is frequently found in ovitraps, and often confused with other common species of Aedes, such as Ae. epactius, Ae. podographicus, Ae. aegypti, and Ae. albopictus. Females of Ae. gabriel are highly anthropophagous and persistent biters in wild habits during the rainy season. Although the medical importance of Ae. gabriel is unknown, its biting habitats and increasing abundance indicate that the potential importance of this species should not be neglected by the public health officials of Mexico.

The mosquitoes (Diptera: Culicidae) of Tabasco, Mexico.

To document and update the mosquito species of Tabasco, Mexico, field collection trips were conducted in the two physiographic regions of Tabasco: the coastal plain of the southern gulf and the mountains of Chiapas and Guatemala. Mosquitoes were collected as immature and adult stages during the dry and rainy seasons from 2014 through 2015. Additionally, the Reference Collection of Arthropods of Medical Importance (CAIM-InDRE) containing mosquitoes of Tabasco was re-examined. In total, 4,913 specimens were collected and examined, which are divided into seven tribes, 18 genera, 27 subgenera, and 104 species. Of these, one genus (Shannoniana Lane and Cerqueira), two subgenera (Georgecraigius Reinert, Harbach and Kitching, and Carrollia Lutz), and 21 species are new records for the mosquito fauna of Tabasco. Culex metempsytus Dyar is a new record for Mexico and Wyeomyia jocosa (Dyar and Knab) is removed from the Mexican mosquito fauna. Seventeen species historically reported were not found in the field collections conducted here. Taxonomic notes, new distribution limits, and comments about the medical importance of species of mosquitoes of Tabasco are discussed. Tabasco is the second state in Mexico with the largest mosquito richness (104 species), followed by Veracruz with 139 species.

DNA barcodes and evidence of cryptic diversity of anthropophagous mosquitoes in Quintana Roo, Mexico.

Culicidae mosquitoes are potential vectors of pathogens that affect human health. The correct species identification, as well as the discovery and description of cryptic species, is important in public health for the control and management of specific vectors. In the present study, the diversity of anthropophagous mosquitoes in Quintana Roo, at the border between Mexico and Belize, was evaluated using morphological and molecular data (COI-DNA Barcoding). A total of 1,413 adult female specimens were collected, belonging to eight genera and 31 morphospecies. Most species formed well-supported clades. Intraspecific Kimura 2 parameters (K2P) distance average was 0.75%, and a maximum distance of 4.40% was observed for Anopheles crucianss.l. ABGD method identified 28 entities, while 32 entities were identified with the BIN system. In Culex interrogator and Culex nigripalpus a low interspecific genetic distance of 0.1% was observed. One undescribed species belonging to the genus Aedes (Aedesn. sp.) was discovered, but no clear genetic divergence was found between this species and the closely related species Aedes angustivittatus. An intraspecific K2P distance greater than 2.7% was observed in Aedes serratus(3.9%), Anopheles crucianss.l. (4.4%), Culex taeniopus (3.7%), Haemagogus equinus (3.9%), Culex erraticus (5.0%), Psorophora ferox (4.5%), and in Anopheles apicimacula(8.10%); therefore, evidences of cryptic diversity are shown in these species. This study showed that DNA barcodes offer a reliable framework for mosquito species identification in Quintana Roo, except for some closely related species for which it is recommended to use additional nuclear genetic markers such as ITS2, in order to resolve these small discrepancies.

Detection of Rickettsia spp. in Rhipicephalus sanguineus (sensu lato) collected from free-roaming dogs in Coahuila state, northern Mexico.

BACKGROUND: The aim of this study was to detect and molecularly identify Rickettsia spp. in Rhipicephalus sanguineus (sensu lato) collected from free-roaming dogs in 30 communities from five municipalities in the south of Coahuila State, northern Mexico, where Rocky Mountain spotted fever is endemic. METHODS: In total, 60 dogs from each municipality were examined for engorged ticks. DNA was isolated from tick pools and conventional PCR assays targeting the 23S-5S ribosomal RNA intergenic spacer and outer membrane protein (ompA) gene of Rickettsia spp. were performed. RESULTS: All ticks (n = 1238) were morphologically identified as R. sanguineus (s.l.). Six pools (each with six engorged females) from four municipalities were positive to Rickettsia spp. DNA sequencing and phylogenetic analyses confirmed the presence of R. rickettsii and R. rhipicephali in R. sanguineus (s.l.) in these ticks. CONCLUSIONS: This study confirms the presence of R. rickettsii and R. rhipicephali in R. sanguineus (s.l.) from stray dogs in the south of Coahuila. This suggests that stray dogs may play a role in the inter-municipal dissemination of infected ticks in this region. Further research is required to assess whether ticks from stray dogs could serve as good indicators for the molecular xenomonitoring of R. rickettsii in this region. Considering that R. sanguineus (s.l.) is a proven vector of R. rickettsii in Mexico, increased awareness regarding permanent tick control in dogs is warranted.