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Introduction: Lagomorphs (rabbits, hares, and pikas) are widely distributed in every continent of the world, except Antarctica. They include 91 species: 31 rabbits of the genera Brachylagus, Bunolagus, Caprolagus, Nesolagus, Pentalagus, Poelagus, Prolagus, Pronolagus, Romerolagus, and Sylvilagus;32 hares of the genus Lepus and 28 pikas of the genus Ochotona. According to the International Union for Conservation of Nature (IUCN 2014), the list of threatened species of lagomorphs includes one extinct, three critically endangered, ten endangered, five near threatened, five vulnerable, 61 of least concern, and six with deficient data. Although a rich diversity of lagomorphs and endemic species exists, some of the wild populations have been declining at an accelerated rate, product of human activities and climate change. In order to evaluate specific conservation actions for species at risk in the near future, the aim of this study is to determine the state of knowledge of endangered and critically endangered species and conservation proposals based on recent studies. This work should serve as a starting point for proposing management and habitat conservation plans for these species and filling the information gaps to address them as soon as possible. Methods:We performed an analysis of the recent trends in the state of knowledge of worldwide endangered and critically endangered lagomorphs, based on the compilation of the recent bibliographic citations in the IUCN list of endangered species (2014), the Lagomorphs Specialist Group of the IUCN web page, and on published studies focusing on these species. Each study was divided into various topics to know those that need to be addressed. We show detailed information for species that are at risk of extinction in the near future (critically endangered and endangered categories), describing the threats to their populations and existing conservation proposals.Results: A total of 13 endangered and critically endangered species of lagomorphs have been the subject of study with a total of 78 contributions, of which the most frequently represented (25) refer to phylogeny, systematics, taxonomy, and evolution, followed by conservation (18), and ecology (14); the least represented are studies of reproduction and morphology with only one each. The critically endangered and endangered species have restricted distributions and in general, their threat factors are introduction of exotic species; habitat loss due to development of human settlements and productive activities; induced fires for the growth of new grass shoots for livestock; poaching; and the presence of predators and feral dogs. Discussion and Conclusions:Worldwide human activities have affected the survival of species of lagomorphs, especially those with restricted distributions. Less than 55 % (7 species) of the total number of species of endangered and critically endangered lagomorphs has been subject of specific study in recent works (2011 to date); moreover, in some cases only one publication was found. Although re...

Climate change (CC) is modifying the habitat and distribution of wild fauna, causing distribution area reduction and/or altitudinal or latitudinal movements of species in response to increased temperatures and changes in precipitation. This increases the risk of species extinction, particularly for those with small population sizes, habitat specialists, microendemics and/or those with already restricted distributions. We examine how the effects of CC could influence the distribution and availability of habitat for the critically threatened and endemic species: the Tehuantepec jackrabbit (Lepus flavigularis) as well as the species of grasses on which it feeds. Our models were constructed using Maxent. Occurrence data of jackrabbits and grasses from the years 1959 to 2014 were analyzed, along with climatic and slope variables for three time periods, present (2014) and future (2050 and 2070). The climatic variables were taken from WorldClim (resolution: 30"), utilizing the HadGEM2-ES model with scenarios 4.5 and 8.5. Potential distribution models estimate an area of 9,274 ha of habitat suitable for the jackrabbit in 2014, with a 19.3% increment in this area to 11,071 ha by 2070 with scenario 4.5 and 9% increment with an area of 10,111 ha by 2070 with scenario 8.5. According to a Jackknife analysis, Precipitation of Wettest Month (BIO13), and Precipitation of Warmest Quarter (BIO18) are the variables that contribute most to the construction of the potential distribution models of L. flavigularis, from 2014 to 2070. Future scenarios (4.5 and 8.5) estimate temperature increase and precipitation reduction in places where jackrabbits and grasses currently inhabit. Also, these scenarios estimate an increase in areas with suitable climatic conditions in the future. However, anthropogenic factors (not considered in this study) have influenced the distribution and retention of the populations of L. flavigularis in the study area, so the outlook of the species is not encouraging. It is clear that CC will have an effect on the distribution of this critically threatened and endemic species, through modification of the area and distribution of its available habitat.El cambio climático (CC) y sus consecuencias sobre las variables climáticas (temperatura, precipitación) pueden poner en mayor riesgo la supervivencia de especies en categoría de amenaza, distribución restringida y/o endémica. Determinamos cómo los efectos del CC influyen sobre la distribución y disponibilidad de hábitat de una especie críticamente amenazada y endémica, la liebre de Tehuantepec, Lepus flavigularis y de las especies de pastos de las que se alimenta. Los modelos fueron elaborados con el programa Maxent, se analizaron datos de ocurrencia de la liebre y de los pastos del año 1959 al 2014, con variables climáticas y pendiente en tres periodos de tiempo, presente (2014) y futuro (2050 y 2070). Las variables climáticas fueron tomadas de WorldClim (resolución: 30"), del modelo HadGEM2-ES para los escenarios 4.5 y 8.5. Los modelos de distribución potencial es...

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