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Background. Mexico is one of the megadiverse countries, harbouring 10% of total worldwide biodiversity. The Yucatan peninsula has 1,010 terrestrial vertebrate species, approximately, however, unfortunately most of them are threatened or in danger of extinction, resulted of degradation, fragmentation, and transformation of habitats. Information generation is a permanent process in the Autonomous University of Yucatan and the Zoology department, to contribute to the conservation and management strategies for wild terrestrial vertebrate species in the region. Objective. To review the most relevant scientific information published by the Department of Zoology during its first 30 years of creation, focused to biology, ecology, zoonosis, diversity, and conservation of vertebrates. Methodology. A compilation of scientific information generated and published by the Zoology department was made mainly focused to biology, ecology, zoonosis, diversity and conservation of terrestrial vertebrates of the Yucatan Peninsula. Main findings. Publications have shown the large amount of information generated mainly in areas of diversity, ecology, zoonosis, and ethnobiology, being the last two areas particularly relevant in the last few years. Scientific collections have contributed largely to the knowledge of the wildlife fauna in the region. Implications. Information is generated by research projects which main objective is to increase the knowledge for supporting the conservation strategies of vertebrates in the Peninsula. Conclusion. The Zoology department has generated relevant information at local, regional, and international level, supporting the present fauna conservation and management strategies in the region.

The future of Aedes aegypti control emphasizes the transition from traditional insecticides toward more sustainable and multisectoral integrated strategies, like using Wolbachia-carrying mosquitoes for population suppression or replacement. We reviewed the integration of the successful Mexican initiative, “Mosquitos Buenos”, with the key challenges outlined in the PAHO guidelines for incorporating innovative approaches into vector control programs. These challenges include establishing essential infrastructure, training personnel, managing field operations, and fostering community support. Our experience provides critical evidence to support the strategic National Plan for implementing and integrating IIT-SIT technologies to control Ae. aegypti and dengue. Furthermore, this experience serves as a foundation for other countries in the region interested in adopting these technologies. It underscores the importance of strategic planning, multisectoral collaboration, continuous evaluation, and scaling up innovative tools to ensure their long-term effectiveness and sustainability in urban areas where Aedes vectors and the diseases they transmit are endemic.

Background The combination of Wolbachia-based incompatible insect technique (IIT) and radiation-based sterile insect technique (SIT) can be used for population suppression of Aedes aegypti. Our main objective was to evaluate whether open-field mass-releases of wAlbB-infected Ae. aegypti males, as part of an Integrated Vector Management (IVM) plan led by the Mexican Ministry of Health, could suppress natural populations of Ae. aegypti in urbanized settings in south Mexico. Methodology/Principal findings We implemented a controlled before-and-after quasi-experimental study in two suburban localities of Yucatan (Mexico): San Pedro Chimay (SPC), which received IIT-SIT, and San Antonio Tahdzibichén used as control. Release of wAlbB Ae. aegypti males at SPC extended for 6 months (July-December 2019), covering the period of higher Ae. aegypti abundance. Entomological indicators included egg hatching rates and outdoor/indoor adult females collected at the release and control sites. Approximately 1,270,000 lab-produced wAlbB-infected Ae. aegypti males were released in the 50-ha treatment area (2,000 wAlbB Ae. aegypti males per hectare twice a week in two different release days, totaling 200,000 male mosquitoes per week). The efficacy of IIT-SIT in suppressing indoor female Ae. aegypti density (quantified from a generalized linear mixed model showing a statistically significant reduction in treatment versus control areas) was 90.9% a month after initiation of the suppression phase, 47.7% two months after (when number of released males was reduced in 50% to match local abundance), 61.4% four months after (when initial number of released males was re-established), 88.4% five months after and 89.4% at six months after the initiation of the suppression phase. A proportional, but lower, reduction in outdoor female Ae. aegypti was also quantified (range, 50.0–75.2% suppression). Conclusions/Significance Our study, the first open-field pilot implementation of Wolbachia IIT-SIT in Mexico and Latin-America, confirms that inundative male releases can significantly reduce natural populations of Ae. aegypti. More importantly, we present successful pilot results of the integration of Wolbachia IIT-SIT within a IVM plan implemented by Ministry of Health personnel. Author summary Wild-type female Ae. aegypti mating with released males carrying the maternally inherited bacteria Wolbachia produce infertile eggs, leading to important reductions in mosquito population size. We present results from pilot open-field mass-releases of Ae. aegypti males infected with the Wolbachia strain wAlbB (termed incompatible insect technique, IIT) and irradiated to prevent accidental female mosquito colonization (termed sterile insect technique, SIT). Our IIT-SIT approach was implemented by the Mexican Ministry of Health within an Integrated Vector Management (IVM) plan to suppress natural populations of Ae. aegypti. Approximately 1,270,000 lab-produced wAlbB-infected Ae. aegypti males were released in a 50-ha. town of Yucatan over a period of 24 weeks. Throughout the suppression phase, we observed significant reductions in egg hatching, outdoor and indoor female Ae. aegypti densities in the release town compared to a similar town used as control. The largest effect was on the number of indoor Ae. aegypti females per house (Prokopack collections) which reached a 90% efficacy. Our study, the first report of an open-field pilot-study with mass-releases of sterile Ae. aegypti males produced with IIT-SIT in Mexico and Latin-America, confirms findings from other settings showing important reductions in entomological indices due to inundative incompatible male releases.

BackgroundThe integration of house-screening and long-lasting insecticidal nets, known as insecticide-treated screening (ITS), can provide simple, safe, and low-tech Aedes aegypti control. Cluster randomised controlled trials in two endemic localities for Ae. aegypti of south Mexico, showed that ITS conferred both, immediate and sustained (~2 yr) impact on indoor-female Ae. aegypti infestations. Such encouraging results require further validation with studies quantifying more epidemiologically-related endpoints, including arbovirus infection in Ae. aegypti. We evaluated the efficacy of protecting houses with ITS on Ae. aegypti infestation and arbovirus infection during a Zika outbreak in Merida, Yucatan, Mexico.Methodology/principal findingsA two-arm cluster-randomised controlled trial evaluated the entomological efficacy of ITS compared to the absence of ITS (with both arms able to receive routine arbovirus vector control) in the neighbourhood Juan Pablo II of Merida. Cross-sectional entomological surveys quantified indoor adult mosquito infestation and arbovirus infection at baseline (pre-ITS installation) and throughout two post-intervention (PI) surveys spaced at 6-month intervals corresponding to dry/rainy seasons over one year (2016-2017). Household-surveys assessed the social reception of the intervention. Houses with ITS were 79-85% less infested with Aedes females than control houses up to one-year PI. A similar significant trend was observed for blood-fed Ae. aegypti females (76-82%). Houses with ITS had significantly less infected female Ae. aegypti than controls during the peak of the epidemic (OR = 0.15, 95%CI: 0.08-0.29), an effect that was significant up to a year PI (OR = 0.24, 0.15-0.39). Communities strongly accepted the intervention, due to its perceived mode of action, the prevalent risk for Aedes-borne diseases in the area, and the positive feedback from neighbours receiving ITS.Conclusions/significanceWe show evidence of the protective efficacy of ITS against an arboviral disease of major relevance, and discuss the relevance of our findings for intervention adoption.

The species diversity composition and phenological behaviour of four braconid subfamilies (Hymenoptera: Braconidae: Agathidinae, Braconinae, Doryctinae and Macrocentrinae) were monitored in three vegetation communities (dune vegetation, tropical deciduous forest and savannah) of the Ria Lagartos Biosphere Reserve (RLBR) in Yucatan, Mexico. Braconid wasps were collected with Malaise traps every 15 days over one year (June 2008 to June 2009). A total of 2,476 specimens were inventoried comprising 233 species and 63 genera. The composition of braconids and their lifestyles differed among the three vegetation communities studied. Doryctinae was the most diverse and abundant subfamily in RLBR (40 genera, 145 species, 990 specimens) and the tropical deciduous forest recorded the maximum abundance and diversity (H’= 4.1; alpha value= 1.059), with 61 exclusive species. Phenological sequence indicates an influence of the rainy season in braconid diversity, but its effects differed among braconid subfamilies and among the vegetation communities. Finally, the importance of the RBRL as a conservation site for this hymenopterous wasp is discussed.

Este estudio describe la fauna de escarabajos estercoleros (Scarabaeidae: Scarabaeinae) en ranchos ganaderos del trópico subhúmedo. De enero a diciembre de 2010 se recolectaron 93 274 escarabajos estercoleros pertenecientes a 17 especies de la subfamilia Scarabaeinae con trampas de caída libre cebadas con excremento de ganado bovino en 4 ranchos ganaderos del oriente del estado de Yucatán, México. Las especies más abundantes fueron Onthophagus landolti, seguida por Canthon indigaceus chevrolati, Digitonthophagus gazella, C. leechi y Pseudocanthon perplexus. Se observó que las especies cavadoras tuvieron mayor abundancia y riqueza; las diurnas de talla pequeña tuvieron menor riqueza pero fueron más abundantes en todo el estudio. El conocimiento de la composición faunística de escarabajos estercoleros de la región es un punto de partida para desarrollar estudios del impacto de las actividades humanas y las prácticas de producción ganadera sobre la diversidad de estos insectos.This study describes the fauna of dung beetles (Scarabaeidae: Scarabaeinae) in tropical sub-humid cattle ranches. Insects were collected with pitfall traps baited with cattle manure from January to December 2010 in four cattle ranches of eastern state of Yucatán, Mexico. 93 274 dung beetles were collected from 17 species of the subfamily Scarabaeinae. The most abundant species were Onthophagus landolti, followed by Canthon indigaceus chevrolati, Digitonthophagus gazella, C. leechi y Pseudocanthon perplexus. Observations showed that burrowing species had greater abundance and species richness. Diurnal species of small size had lower richness, but were more abundant. Knowledge of the composition of dung beetle fauna of the region is a starting point to develop studies of the impact of human activities and livestock production practices on the diversity of these insects.

Scarabaeinae are sensitive to structural habitat changes caused by disturbance. We compared copronecrophagous beetle (Scarabaeinae) community structure in three differently managed zones within an agroecosystem of the northern Yucatan Peninsula, Mexico. We placed dung and carrion traps once a month from June 2004 through May 2005. The beetle community included 17 species from the genera Canthon, Canthidium, Deltochilum, Pseudocanthon, Malagoniella, Onthophagus, Phanaeus, Copris, Uroxys, Sisyphus and Ateuchus. The secondary vegetation had a higher beetle diversity than the other two zones. Species richness was highest in the Brosimum alicastrum plantation. The pasture had the lowest species diversity and richness, but exhibited the highest abundance of Scarabaeinae in the dry season. The two zones with extensive tree cover were the most diverse. Roller beetles were dominant over burrower species and small-sized species outnumbered large species. Our data show two important issues: beetle species in the pasture extended their activity to the beginning of the dry season, while abundances dropped in the other, unirrigated zones; and the possibility that the Scarabaeinae living in neotropical forests are opportunistic saprophages and have specialized habits for resources other than dung. The B. alicastrum plantation is beneficial to the entire ranch production system because it functions as a dispersion and development area for stenotopic species limited to tree cover. Rev. Biol. Trop. 55 (1): 83-99. Epub 2007 March. 31.Este estudio describe y compara la estructura de la comunidad de escarabajos copronecrófagos (Scarabaeinae) en tres zonas con diferente manejo al interior de un agroecosistema localizado en el norte de la Península de Yucatán. A lo largo de un año de muestreo sistemático se encontraron 17 especies de los géneros Canthon, Canthidium, Deltochilum, Pseudocanthon, Malagoniella, Onthophagus, Phanaeus, Copris, Uroxys, Sisyphus y Ateuchus. El área de vegetación secundaria tuvo la comunidad más diversa. En la plantación de Brosimum alicastrum (ramón) se encontró la mayor riqueza de especies. El potrero tuvo la menor riqueza y diversidad, pero en él se observó la mayor abundancia de Scarabaeinae en la estación seca. Las áreas con mayor cobertura arbórea tuvieron mayor diversidad y se encontró dominancia de las especies rodadoras sobre las cavadoras y de las especies de talla pequeña sobre las de tamaño grande. Nuestros datos muestran dos aspectos importantes: en el potrero (con riego) las especies de escarabajos extienden su actividad hasta el inicio de la época seca, mientras que las abundancias decaen en las áreas que no reciben riego; la posibilidad de que los Scarabaeinae neotropicales sean saprófagos oportunistas y tengan hábitos alimenticios especializados para disponer de otros recursos además del excremento. El ramonal beneficia al sistema completo pues provee de un espacio para la dispersión y permanencia de varias especies estenoecas a la cobertura vegetal.

Background. Macrocyclic lactones (ML) are effective in controlling endo- and ectoparasites in livestock. ML, specially ivermectin and moxidectin, have a typical pharmacokinetic profile of lipophilic molecules with slow degradation and when administered to livestock are excreted in the faeces almost unaltered. ML released into the environment, can cause lethal and sublethal effects on dung beetles (DB). Objective. To document the main scientific contributions of our research group to the awareness of the adverse effect of ML on DB associated with livestock environments under grazing systems. Methodology. The compilation of scientific articles from the studies carried out by a research group in the first 50 years of the FMVZ-UADY was carried out. Results. The studies have shown that ML (IVM-1%, IVM-3.15%, MOX-10%) in dung from cattle treated with injectable formulations had a sublethal effect on DB. For the species Canthon indigaceus chevrolati dung from cattle treated with injectable formulations of IVM (1% and 3.15%) and MOX (1% and 10%) do not produce lethal and sublethal effects. Faecal ivermectin residues may induce changes in attraction of some neotropical DB species to dung pats. Implications. Current ML application methods may have negative effects on the environmental services provided by dung beetles, and therefore need to be modified to minimize any impacts they might have on these vital members of tropical livestock systems. Conclusions. The review shows the adverse effects of ML on DB in the Mexican tropics; however, for the C. i. chevrolati, dung from cattle treated with IVM and MOX, do not produce lethal and sublethal effects, which suggests some type of tolerance